ddokbaro/KCI_data · Datasets at Hugging Face

id stringlengths 12 12	format stringclasses 2 values	title_ko stringlengths 0 811 ⌀	title_en stringlengths 0 1.26k ⌀	journal dict	authors listlengths 0 15	abstract_ko stringlengths 0 4k ⌀	keywords stringclasses 157 values	citation_count stringclasses 5 values	doi stringlengths 0 127 ⌀	file_source stringlengths 23 23
ART001959932	oai_dc	압전 밸브용 압력 레귤레이터	Pressure Regulator for Piezoelectric Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "윤소남(한국기계연구원); 김찬용(한국기계연구원); 서우석(한국기계연구원); 박중호(한국기계연구원); 함영복(한국기계연구원)" ]	The pressure regulator which is used for controlling the reducing pressure in the piezoelectrically driven pneumatic valve has been studied. The pneumatic valve of this study object is 2-stage type and consists of a piezoelectric actuator, a controller, a poppet valve and a pressure regulator. Nominal flow of 50 1pm, maximum operating pressure of 0.9MPa and frequency characteristic of 10Hz and over are required in this pneumatic valve, but the pressure regulator is needed because piezoelectric actuator has no ability to control the pressure of 0.9MPa directly. In this study, bimorph type PZT actuator of 25.2 mm(L)x7.2 mm(W)x0.5 mm(H) with constant of -220x10-12 CN-1 was proposed and investigated. Maximum operating force of 0.052 N and maximum displacement of 63 ㎛ were gotten from the fabricated PZT actuator. From the analysis results, the orifice diameter or 0.6mm for a piezoelectric actuator was derived and then the pressure regulator which can be operated under 0.15 MPa easily was designed and manufactured. Performance and effects of design parameters were simulated by the Simulink of Matlab software, and it was confirmed that the performance characteristics of manufactured pressure regulator are superior in the common use pressure of 0.5 MPa to 0.7MPa, The results show that the proposed pressure regulator is suitable for the pneumatic valve with a PZT actuator.	기계공학	null		kci_detailed_000118.xml
ART001959934	oai_dc	굴삭기 리턴 라인 유동소음 감소에 관한 연구	Research of Noise Reduction about Excavator Return Line	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "강병일(두산인프라코어(주)); 장달식(두산인프라코어); 김성재(두산인프라코어(주)); 권영식(두산인프라코어(주))" ]	In this paper the noise source and the amplifying mechanism are analyzed to reduce the noise of the excavator return line using the experimental approach and the CFD simulation. The result says that the reason of noise generation and pipe vibration caused by the cavitation at the main control valve and the level of noise is proportional to the valve back pressure at the return line. The methodology to reduce this noise was proposed and verified by the vehicle test.	기계공학	null		kci_detailed_000118.xml
ART001959937	oai_dc	유압 호스에서의 주파수 계열 음속 계측법 개발	A Method for Measuring the Frequency Series Wave Speed in Hydraulic Hose	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "강만곤(부경대학교); 이일영(부경대학교)" ]	With the increasing concerns on noise and vibration in hydraulic fluid power systems, it is Important to find better way to reduce noise and vibration. In this study, the authors survey former researches on hose(viscoelastic tube) modeling in advance. And a summary of several existing methods for measuring the speed of sound in the fluid in pipes is presented. Their basic principles, advantages and limitations are compared. And The authors suggest a for simple identification procedure to obtain wave speed in hose by just using an experimental pressure data for the object tube with hose. In the new procedure, flow in hose is basically modeled by transfer matrix method, and ware speed in hose is obtained as data in frequency series. The wave speed in hose as data in frequency series will be used to compute the pressure pulsation attenuation in hydraulic pipe systems. The computed results are compared with the experimental ones, and the validity of the new procedure to obtain wave speed in hose is confirmed.	기계공학	null		kci_detailed_000118.xml
ART001959935	oai_dc	전기∙유압 서보 시스템의 제어성능 비교	Comparison of Control Performance in Electro∙hydraulic Servo Systems	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김도태(경일대학교); 박경섭(경일대학교)" ]	A controller design procedure for an electro-hydraulic positioning systems has been developed using H∞ control. The generalized plant models and weighting function for multiplicative uncertainty modelling error was presented along with H∞ controller designs in order to investigate the robust stability and performance. Both disturbance rejection and command tracking performances were improved with H∞ controller, and the better uniformity of time response is achieved across wide range of operating conditions than the PID,LQR and LQG control scheme. The multiplicative uncertainty case was specifically suited for the design of an electro-hydraulic positioning control systems using H∞ control.	기계공학	null		kci_detailed_000118.xml
ART001959926	oai_dc	유압서보밸브의 인-프로세스 성능 진단에 관한 연구 1 - 유압실린더 위치제처계의 경우 -	A study on In-Process Performance Diagnosis of Hydraulic Servovalves - First Report : position Control System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 김경호((주) TFS Global); 송재수(주) TFS Global); 함영복(한국기계연구원); 이재천(계명대학교)" ]	In this paper, an in-process diagnosis method for performance of position control servo system was studied, which was based upon null bias, slew-ratio and delay time measurement. Slew-rate ratio and delay time were analyzed by theoretical analysis, computer simulation and experiment. As a result of these analysis, when spool of servovalve was weared, slew-rate ratio was decreased and delay time was increased.	기계공학	null		kci_detailed_000118.xml
ART001959929	oai_dc	공압실린더의 누설유량 계측방법에 관한 연구	A Study on the Measurement Method of Leakage Flow-rate for Pneumatic Cylinder	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "장지성(부경대학교); 지상원(부경대학교 제어기계공학과); 정지현(부경대학교); 강보식(한국기계연구원)" ]	In this study, a measurement method of leakage flow-rate for pneumatic driving apparatus is proposed. The existing measurement methods of leakage flow-rate of air need disassemble the test component. Therefore, there is no effective method to measure the leakage flow-rate while operating pneumatic driving apparatus. In this study, the leakage flow-rate is measure form the pressure change in an isothermal chamber that can realize isothermal conditions by stuffing steel wool into it. Therefore, wide range of flow-could be measured only from the pressure response and the leakage flow-rate can be measured during operating pneumatic driving apparatus. The effectiveness of the proposed method is proved by experimental results.	기계공학	null		kci_detailed_000118.xml
ART001959924	oai_dc	MR 밸브 내장형 서보 액추에이터의 힘 제어에 관한 연구	A study on the force control of a servo actuator with built-in MR Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "안경관(울산대학교); 송주영(울산대학교 대학원); 김정수(울산대학교); 안영공((재)송도테크노파크); 박중호(한국기계연구원)" ]	A servo actuator with a valve using MR (Magneto-Rheological) fluid is proposed for fluid control systems. The MR fluid is well known as a functional fluid whose apparent viscosity is controlled by the applied magnetic field strength. The pressure in the MR cylinder can be controlled by the applied magnetic field strength. Good points of the MR cylinder are more simple, compact and reliable structure than a conventional oil hydraulic cylinder. The experimental results show that the MR cylinder could used as a servo actuator.	기계공학	null		kci_detailed_000118.xml
ART001959907	oai_dc	공압시스템의 설계 파라미터 최적화	Optimization of Design Parameters of a Pneumatic System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "엄태준(순천향대학교)" ]	This paper presents optimization of a pneumatic control system whose design parameters have been optimized so that the desired dynamic characteristics of cylinder position was obtained. The pneumatic system is used as transferring and stacking equipment for solid freeform fabrication system which has been widely used in design verification applications. The pneumatic system mainly consists of pneumatic control valves and cylinders. The system was modeled by using several principles for pneumatic components. The system was optimized to obtain dynamic performance with enough damping to reduce cylinder vibration. A fuzzy controller has been applied to fulfill the dynamic performance requirements of the pneumatic system. The simulation results show that the fuzzy controller is more effective than a PD controller.	기계공학	null		kci_detailed_000118.xml
ART001959917	oai_dc	유압펌프 및 모터 피스톤 조립체의 수명예측을 위한 가속실험 모델	Accelerated Life Test Model for Life Prediction of Piston	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이용범(한국기계연구원(신뢰성평가센터)); 김형의(한국기계연구원); 유영철(한국기계연구원); 박종호(충남대학교)" ]	The safety factor of hydraulic piston & motors due to high pressurization, high speedization and low weight/volume realization to enhance the output density shows a tendency to decrease. Therefore more effective test methods are necessary to predict the exact life. The failure of hydraulic pumps & motors operating in high pressure and high speed mainly occurs in piston-shoe assemblies, and the major failure mode is wearout of the shoe surface. The sensitive parameters in the endurance life test are speed, pressure and temperature, and the failure production increases in proportion to the operating time. In this research, the authors propose the combined accelerated life test model using the analysis method of the combined accelerated life test results of piston-shoe assemblies by applying simultaneously high speed, high pressure and high temperature in accordance with variation of speed, pressure and temperature to reduce the life test time.	기계공학	null		kci_detailed_000118.xml
ART001959910	oai_dc	VSC 유압유닛의 압력 추정기 및 제어기 설계에 관한 연구	A Study on Estimator and Controller Design of VSC Hydraulic Unit	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이교일(서울대학교); 김범주(서울대학교); 유승진(서울대학교)" ]	This paper presents modeling and estimator/controller design for the hydraulic system in Vehicle Stability Control(VSC) system. A nonlinear mathematical model of the VSC hydraulic system is proposed and its accuracy is experimentally verified. A brake pressure estimator is then designed based on the derived mathematical model of VSC hydraulic system. And a disturbance observer, which compensates the estimation error between the brake pressure and the computed brake pressure is also designed to enhance the accuracy of the estimator. The proposed controller has the from of a feedback controller and determines explicitly the on/off ratio of valves' driving PWM signals by means of making use of the simplified mathematical model in the VSC hydraulic system. The performance of the designed controller whose signal is generated by the brake pressure estimator is validated through experimental results.	기계공학	null		kci_detailed_000118.xml
ART001959918	oai_dc	기어펌프∙모터 이끝 틈새의 영향에 관한 연구	A Study on the Effect of Gear Teeth End-Gaps for Hydraulic Gear Pumps and Motors	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정헌술(군산대학교); 풍려려(군산대학교); 오석형(군산대학교)" ]	In order to improve the efficiency of hydraulic gear pumps or motors especially for high operating pressure, power losses due to viscous friction and leak flow through gear teeth end-gaps are considered in this paper. Optimal gaps minimizing the power loss for pumps and motors with uniform heights of gaps are analysed first. And the effect of the shapes of gaps with unequal heights on the power loss are studied and discussed by simulation. Considering that the outer shell facing gear teeth may expand due high internal pressure or thermal stress, the results drawn in this paper can be used for the design of high efficiency pumps and motors.	기계공학	null		kci_detailed_000118.xml
ART001959905	oai_dc	액시얼 피스톤 펌프의 맥동유량 시뮬레이션 모델	Flow Ripple Simulation Model of Axial Piston Pump	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이일영(부경대학교); 박정환(부경대학교); 강만곤(부경대학교)" ]	This paper presents a theoretical study of the delivery flow ripple produced by a swash plate type hydraulic piston pump for the purpose of developing a computer simulation program capable of predicting the pump source flow ripple accurately at the design stage. Particular attention has been paid to the development of the theoretical model by clarifying quantitatively the design influences of key parts of valve plate such as relief groove and pre-compression/expansion.	기계공학	null		kci_detailed_000118.xml
ART001959898	oai_dc	비례솔레노이드 형상 최적설계에 관한 연구	A Study on Shape Optimization of Electro-Magnetic Proportional Solenoid	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "윤소남(한국기계연구원); 함영복(한국기계연구원); 강정호(삼성종합기술원)" ]	There are two types of solenoid actuator for force and position control of the fluid power system. One is an on-off solenoid actuator and the other is an electro-magnetic proportional actuator. They have some different characteristics for attraction force according to solenoid shape. Attraction force of the on-off solenoid actuator only depends on flux density. And the stroke-force characteristics of the proportional solenoid actuator are determined by the shape of the control cone. In this paper, steady state characteristics of the solenoid actuator for electro-hydraulic proportional valve determined by the shape of control cone are analyzed using finite element method and it is confirmed that the proportional solenoid actuator has a constant attractive force in the control region independently on the stroke position. And the shape of control cone optimized using 1+1 evolution strategy to get a constant force, In the optimization algorithm, control cone length, thickness and taper length are used as a design parameter.	기계공학	null		kci_detailed_000118.xml
ART001959903	oai_dc	압전액추에이디터를 이용한 비례 가스유량제어밸브	Proportional Gas Flow Control Valve Using Piezo Actuator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "윤소남(한국기계연구원); 김찬용(경북대학교); 함영복(한국기계연구원); 이경우(경원 훼라이트공업㈜); 강정호(삼성종합기술원)" ]	A household gas valve is used for flow control of LPG(Liquefied Petroleum Gas) or LNG(Liquefied Natural Gas) of which pressure is about 20㎜(≑0.0196 [bar]). Currently, two kinds of valves such as rotary type and button type are widely used in many applications. But, these valves have some problems that they are not controllable and reliable. Piezo actuation combined with modem microelectronics provides a reliable, quiet, low energy, infinitely adjustable gas valve. In this paper, gas valve using piezo actuator which are bimorph and a circle type was studied. Also, Prototype for gas valve was manufactured and characteristics of the prototype gas valve were analyzed.	기계공학	null		kci_detailed_000118.xml
ART001968153	oai_dc	토크모터의 정특성과 동특성 해석	An Analysis of Static and Dynamic Characteristics of Torque Motor	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "허준영(한국기술교육대학교); 박창순(한국기술교육대학교)" ]	In the early of 1950, the high response magnetic torque motor was developed for driving electro-hydraulic servo valves. Since then it has been broadly used for industrial application and the research of development or improvement of the torque motor is still being conducted. The purpose of this study is to present useful design criteria for the torque motor design. For this, torque motor is modelled and linearized. The static characteristics of the torque motor are investigated by direct computation of the derived linearlized equations. The dynamic characteristics of the torque motor are investigated with the derived transfer function by using Matlab and compared with the results of the linearlized analysis by using AMESim simulation with actual values of the physical parameters. Finally, the design criteria obtained from the analysis are reviewed.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2015.12.1.009	kci_detailed_000118.xml
ART001968176	oai_dc	선박 유압 조타장치 부하의 추정	Estimation of Load on Ship's Hydraulic Steering Gear	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "지상원(부경대학교 기계시스템공학과); 이일영(부경대학교); 정은석(한국해양대학교); 김병곤(유원산업); 오재민(부경대학교)" ]	For testing a newly designed ship's steering gear, a steering gear test bench with a steering gear to be tested and a load generation part should be prepared. The load given to the steering gear has to be pertinent to the load generated in a targeted ship. In this study, the authors suggest a process of estimating the load given to steering gears in ships. At first, a test for measuring the load in the steering gear of a real ship was conducted. Then, a process was developed to compute rudder driving torque and force by using basic equations including some empirical equations on ship's steering. The test results and the computation results on the load in the steering gear were compared, As a result, the process suggested in this study for estimating load in ship's steering gears was verified.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2015.12.1.015	kci_detailed_000118.xml
ART001968179	oai_dc	로드리스 실린더의 수명 특성에 관한 연구	A Study on the Life Characteristic of Rodless Cylinder	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이충성(한국기계연구원); 강보식(한국기계연구원); 임재학(한밭대학교)" ]	Pneumatic cylinders are classified into rod-type pneumatic cylinders and rodless pneumatic cylinders depending on the presence of the rod. Rodless cylinders have a constant area and have no deflection. Rodless cylinders are widely used in automatic systems requiring high-speed performance and high-precision transportation. However, the research of the pneumatic cylinder has been focused on the structure and life characteristics. In this research, aging characteristics and shape parameter analysis which are related to the lifetime were investigated. By conducting the lifetime tests with two different materials for the transfer plate, the failure mode and lifetime characteristics were analyzed. By the Anderson-Darling (A-D) verification based on the complete data set, the analysis results of lifetime distribution, shape parameter, and scale parameter were provided.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2015.12.1.021	kci_detailed_000118.xml
ART001968151	oai_dc	A Study on Thermal Analytical Model for a Dry Dual Clutch	A Study on Thermal Analytical Model for a Dry Dual Clutch	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "Liu, Hao(계명대학교); 이재천(계명대학교); 노유정(계명대학교); 조종환(평화발레오); 이희락(평화발레오); 고재욱(평화발레오); 강지우((주)평화발레오)" ]	The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2015.12.1.001	kci_detailed_000118.xml
ART001857195	oai_dc	CFD를 이용한 유압 서보밸브의 열유체 해석	THD Analysis of a Hydraulic Servo Valve Using CFD	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정요한(경상대학교 대학원 기계항공공학부); 박태조(경상대학교)" ]	Hydraulic servo valves are widely used in various fluid power systems because of their fast response and precision control. In this paper, we studied the effect of metering notch shapes and amount of their openings on the flow characteristics within the spool valve using a computational fluid dynamic (CFD) code, FLUENT. To obtain the results for more realistic operating conditions, viscous heating due to the jet flow and viscosity variation of the hydraulic fluid with temperature were considered. For two types of notch shape, streamlines, oil temperature and viscosity distributions, and variations of flow and friction forces acting on spool were showed. The flow and friction forces affected by the metering notch shapes and their openings, and oil temperature rise near metering notch was significant enough to results in the jamming phenomenon. A thermohydrodynamic (THD) flow analysis adopted in this paper can be used in optimum design of hydraulic servo valves.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.1.008	kci_detailed_000118.xml
ART001857183	oai_dc	Application of Secondary Control Hydrostatic Transmission in A Multi-Point Absorbing Wave Energy Converter	Application of Secondary Control Hydrostatic Transmission in A Multi-Point Absorbing Wave Energy Converter	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "도황팅(울산대학교); 안경관(울산대학교)" ]	This paper presents a novel concept of wave energy converter for electric generation from the ocean wave energy. In this paper, a Multi-Point Absorbing Wave Energy Converter, shortened as MPAWEC by using Secondary Control Hydrostatic Transmission (SCHST) was proposed. The power take-off (PTO) system in the proposed MPAWEC includes multi heaving buoys to drive hydraulic pumps placed at different points. The application of SCHST in MPAWEC gives some advantages, such as longevity of hydraulic components; more energy is harvested; the variation of the pressure in the accumulator limited; therefore the accumulator volume is reduced and the output speed is more stable, etc. A PID controller was designed for speed control of the hydraulic motor. The simulation results indicated that the speed of the generator was ensured with the relative error as 0.67%; the efficiency of the proposed system was 71.4%.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.1.001	kci_detailed_000118.xml
ART001857215	oai_dc	Analysis of the Mathematical Model of a Variable Displacement Vane Pump for Engine Lubrication	Analysis of the Mathematical Model of a Variable Displacement Vane Pump for Engine Lubrication	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "딩광청(울산대학교); 안경관(울산대학교); 이재신(울산대학교)" ]	Variable displacement vane-type oil pumps represent one of the most innovative pump types for industrial applications, especially for engine lubrication systems. This paper presents a complete and accurate mathematical model for a typical variable displacement vane-type oil pump. Firstly, its theoretical model is revised. Secondly, an analysis of power loss factors of this pump type is carefully investigated to optimize the modeling accuracy. Finally, the estimated pump performance using the complete pump model is verified by numerical simulations in comparison with the practical tests.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.1.014	kci_detailed_000118.xml
ART001959422	oai_dc	에어밸런서 공압 회로의 설계 및 성능 실험	Pneumatic circuit design and Performance test of Air balancer	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원)" ]	Air balancer is a conveyance cargo-handling machine, used in assembly and process lines of car and machining industries. This can lift up an object, the weight of which is from 5 to 200 kg, and moves it to a position. As industrial technologies evolve, it is required to move an object and fit it into a specified position with greater accuracy, rather than performing simple tasks such as lifting objects up and down as conventional ones do. There is also a demand to handle an object with one hand, rather than with two hands. Through designs of manifold unit for an air balancer funcion, pilot regulator unit to keep pressure constant, hand unit for an accurate load perception function, and air balancer circuit, this study enables everybody to work it with ease and convenience. Experiments and comparisons were conducted for the performance evaluation of the circuit.	기계공학	null		kci_detailed_000118.xml
ART001959419	oai_dc	굴삭기 시뮬레이터의 설계	Design of Simulator for the Excavator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원); 김정수(한국기계연구원)" ]	Recently, the cylinder of excavator is applied in the various environment. So, we need the development of the simulator for the excavator. The excavator has the effects of the decrease of the cost and improvement of the cylinder's performance. In this paper, we design the simulator for the excavator and makes an analysis of the dynamics and structure. The simulator was applied to the excavator's models of 10ton, 20ton and 30ton because we built the data base of a real excavator's cylinder of information in the experiment. And we used the FEM analysis for the comparative study on the characteristics.	기계공학	null		kci_detailed_000118.xml
ART001959413	oai_dc	유압시스템 구성품의 수명시험을 위한 무고장 시험시간의 산출	Determination fo No-Failure Test Times for the Life Test of Hydraulic System Components	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성래(건양대학교); 김형의(한국기계연구원)" ]	It is very important for the manufacturers to predict the life of hydraulic system components according to the results fo life tests. Since it takes too much time to test the hydraulic system components until fuilure, the no-fuilure test method is applied for the life test of them. If the shape parameter of Weibull distribution, the number of samples, the confidence level, and the assurance life are given, the no-fuilure test times of hydraulic system components can be calculated by given equations. Here, the procedures to obtain the no-fuilure test times of the hydraulic system components such as hydraulic motors and pumps, hydraulic cylinders, hydraulic valves, hydraulic accumulators, hydraulic hoses, and hydraulic filters are described briefly.	기계공학	null		kci_detailed_000118.xml
ART001959405	oai_dc	시일이 없는 유압 실린더용 피스톤의 이론해석	Theoretical Analysis of Sealless Piston for Hydraulic Cylinders	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "박태조(경상대학교)" ]	In this paper, a theoretical analysis is carried out to study the lubrication characteristics of sealless piston for hydraulic cylinders. The analytical pressure distributions are obtained solving one-dimensional Reynolds equation with partially tapered moving piston. Nearly analytical expressions for lateral forces acting on the piston and leakage flow rate through the clearance are also presented. Using the analytical expressions, the influence of design parameters on lubrication characteristics can be easily evaluated without numerical analysis. Composite-shaped piston which minimizes the leakage flow rate is the optimum in sealless piston for hydraulic cylinder.	기계공학	null		kci_detailed_000118.xml
ART001932915	oai_dc	직접제어 방식을 이용한 소형 지게차 변속감도 시뮬레이션에 관한 연구	A Study on Simulation of Shift Sensitivity of Small Forklift Transmission using Direct Control Method	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정영만(울산대학교); 양순용(울산대학교)" ]	The transmission control method of a small forklift is classified into a pilot control method and a direct control method. In the pilot control method, the complex hydraulic circuit consists of many components, making the production process too costly and time consuming. The direct control method contains fewer components that can be configured to simple hydraulic circuits. As another advantage, the input profile easily changes the shift sensitivity of the transmission. Therefore, this research considers the characteristics of the direct control method in the development of hydraulic system design. This paper will present a simulation of the direct control transmission using AMESim. First, modeling of the direct control method is obtained and simulated with real parameters. The simulation results then are carried out and compared with the experimental results to verify and analyze the characteristics of the direct control method.	기계공학	null		kci_detailed_000118.xml
ART001932935	oai_dc	EHA 밸브 성능시험 장치 개발	Development of Performance Test Equipment for Easy-Hill Assist Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교)" ]	When a manual transmission equipped car stops on an incline where the nose of the car is higher than the rear, hill-start control or hill-holder could prevent the vehicle from rolling backward as the car moves forward. The easy-hill assist valve consists of a check valve and a needle type ON/OFF solenoid valve connected in parallel; it is a hydraulic actuator that can maintain brake pressure using an electrical signal from the ECU. As the EHA valve is a safety-related component of the brake system, high reliability as well as superior dynamic performance is required for it to be applied in commercial vehicles. This paper presents the design of the EHA valve as a piece of equipment that can simulate the brake actuation pressure with a pressurizing piston. Following specific test standards, the experimental results validate the implemented functions of the test equipment, proving the test stand to be effective for the performance and endurance of the EHA valve.	기계공학	null		kci_detailed_000118.xml
ART001932917	oai_dc	에너지보존과 토크평형을 이용한 제로터 유압모터의 배제용적 해석-내부로터 공·자전 경우-	An Analysis on Volumetric Displacement of Gerotor Hydraulic Motor using Energy Conservation and Torque Equilibrium - Second Report: The Case of a Revolving and Rotating Inner Rotor -	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 함영복(한국기계연구원); 김대명((주)대화산기)" ]	It is difficult to analytically derive a volumetric displacement formula for a gerotor hydraulic motor due to the complexity of the geometric shape of its gear lobes. This work proposes an analytical method for the volumetric displacement, a relatively easy method based upon two physical concepts: conservation between hydraulic energy and mechanical shaft energy, and torque equilibrium for the rotor’s motion. The first research using these concepts was conducted on inner and outer rotors rotating with respect to each rotor axis. This work represents the second report conducted on an inner rotor revolving as a planetary motion on the stationary outer rotor. The formula equations regarding the volumetric displacement and flow rate are derived, and the proposed formula about the volumetric displacement is proven to be the same as another analytical displacement formula: the so-called vane length method. From the formula, volumetric displacement is calculated for an example geometry of the gear lobes. The resultant displacement is confirmed to be the same as the value calculated from the chamber volume method. The proposed analytical formula can be utilized in the analysis and design of gerotor hydraulic motors. Because it is based on torque equilibrium, this formula can provide a better understanding of torque performance, such as torque ripple, in designing a gerotor type motor.	기계공학	null		kci_detailed_000118.xml
ART001932919	oai_dc	DLC 코팅에 의한 사판식 피스톤 펌프의 저속 영역 동력 손실 개선	Performance Improvement of a Swash Plate Type Piston Pump in the Low-Speed Range by a DLC Coating	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "홍예선(한국항공대학교); 김종혁(한국항공대학교); 이성렬(한국항공대학교)" ]	This paper details application of a DLC(Diamond Like Carbon)-coating to the swash plate and the ball joint of pistons that make sliding contact with the piston shoes of an axial piston pump. This process, aimed to reduce the frictional and leakage power losses of the hydrostatic piston shoe bearings at the low speed range. At lower speeds than 100rpm, the positive effects of the DLC-coating on the power loss reduction of the hydrostatic piston shoe bearings could be confirmed. These effects resulted in little improvement in volumetric efficiency of the test pump, but the mechanical efficiency could be raised by up to 5% at 100rpm; here, the DLC-coated swash plate played a more dominant role than the DLC-coated ball joint.	기계공학	null		kci_detailed_000118.xml
ART001932920	oai_dc	유전자 알고리즘과 콤플렉스법에 의한 고성능 유압휴즈의 최적 설계	Optimal Design of a Quick-Acting Hydraulic Fuse using Genetic Algorithm and Complex Method	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성래(건양대학교)" ]	The hydraulic fuse, which responds to the suddenly increased flow on rupture of a line and shuts off the fluid flow, would prevent large spillage of liquid. The quick-acting hydraulic fuse, which is mainly composed of a poppet, a seat, and a spring, must be designed to minimize the leaked flow and to prevent high collision speed between the poppet and seat during fuse operation on a line rupture. The optimal design parameters of a quick-acting hydraulic fuse were searched using the genetic algorithm and the complex method that are kinds of constrained direct search methods. The dynamic behavior of a quick-acting hydraulic fuse was researched using computer simulations that applied the obtained optimal design parameters.	기계공학	null		kci_detailed_000118.xml
ART001932933	oai_dc	가변 용적형 사판식 피스톤 펌프의 회전 속도 조절에 의한 정압 제어 소비 동력 절감	Reduction of Power Consumption for Constant Pressure Control of Variable Swash Plate-type Piston Pump by Varying the Pump Speed	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김종혁(한국항공대학교); 홍예선(한국항공대학교)" ]	This paper proposes a control scheme to reduce the power consumption of a variable displacement swash-plate type piston pump supplying oil to a valve-controlled hydraulic cylinder at constant pressure. Whenever flow rate demand was absent, the swash plate angle and the pump speed were changed to the minimum values required to compensate for the internal leakage flow. In response to command signals, the pump speed was changed in proportion to the absolute mean value of the speed component for position commands. At the same time, a pressure regulator was activated to maintain constant system pressure by precisely adjusting the pump speed with the swash plate angle fixed at the maximum. The conventional system consisting of a pressure-compensated variable displacement type pump is driven at a constant speed of 1,800rpm. By comparison, computer simulation and experimental results showed that idling power at stand-by status could be reduced by up to 70% by reducing the pump speed from 1,800rpm to 300rpm and the swash plate angle to the minimum.	기계공학	null		kci_detailed_000118.xml
ART001932925	oai_dc	유압식 굴삭기의 고효율 화에 관한 새로운 접근	A New Approach to the High Efficiency of Hydraulic Excavator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이용범(한국기계연구원 시스템신뢰성연구실)" ]	With recent oil price increases, the fuel efficiency of hydraulic excavators has become a serious issue. Researchers have considered weight lightening by high pressurization in order to improve the efficiency of the excavator and pump controlled actuation (PCA) and to reduce pressure loss of hybrid and valves using mechanical inertia. However, high pressurization is not very effective because the excavator operates at a low speed; a hybrid is inefficient because little accumulated inertial energy is accumulated; and PCA is ineffective because control precision and responsibility are low. In this study, a method to minimize air and gas in hydraulic oil has been presented as a simple and new way to increase hydraulic efficiency.	기계공학	null		kci_detailed_000118.xml
ART001932929	oai_dc	상용해석 툴을 이용한 소형 스크류 디캔터의 설계에 관한 연구	A Study on Design of Small Type Screw Decanter using Commercial Analysis Tool	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김용석(울산대학교); 김종태(신정뉴테크(주)); 양순용(울산대학교)" ]	This study suggests a small-sized screw decanter specialized for dredging sites. Generally, conventional screw decanters are composed of a cylinder and a cone. However, the suggested screw decanter simply has a cone based on a cone-type bowl structure. In this research, a commercial analysis tool is used to establish an optimal design for the bowl and the screw conveyor. Moreover, the base frame, where the main bearings that support the spindle of the bowl and the screw conveyor are installed, is optimally designed considering the weight of the rotating body and the deflection caused by the high centrifugal force. Furthermore, the natural frequency range of the spinning body, the bowl and the screw conveyor, is applied to this base frame; it is designed not to correspond to the resonance frequency range and achieves stability as a result. This study suggests an optimal design for the rotating body and the base frame of a screw decanter considering its vibration characteristics. Such a design will prevent overuse of materials and help to reduce the weight and volume—and the price—of a screw decanter.	기계공학	null		kci_detailed_000118.xml
ART001932913	oai_dc	Position control of Electro Hydraulic Actuator (EHA) using an Iterative Learning Control	Position control of Electro Hydraulic Actuator (EHA) using an Iterative Learning Control	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "도안녹치남(울산대학교); 우엔민트리(울산대학교); 박형규(울산대학교); 안경관(울산대학교)" ]	This paper presents the development of a compact position generator to be used for industrial purposes based on a pump controlled Electro-Hydraulic Actuator (EHA), which is closed-loop controlled by an embedded based Iterative PID controller. The controller is designed by combining the PID controller and the iterative learning scheme to perform tracking control for periodically desired references. Control algorithm is implemented on an embedded computer (AD 7011-EVA) which makes the implementation and application in industrial environments easier.	기계공학	null		kci_detailed_000118.xml
ART002080080	oai_dc	트랙터 자동변속기 되먹임 변속 제어기 설계	Feedback Shift Controller Design of Automatic Transmission for Tractors	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교); 정창도(타이코에이엠피); 박세하(타이코에이엠피유한회사)" ]	Nowadays automatic transmission equipped vehicles prevail in construction and agricultural equipment due to their convenience in driving and operation. Though domestic vehicle manufacturers install imported electronic controlled transmissions at present, overseas products will be replaced by domestic ones in the near future owing to development efforts over the past 10 years. For passenger cars, there are many kinds of shift control algorithms that enhance the shift quality such as feedback and learning control. However, since shift control technologies for heavy duty vehicles are not highly developed, it is possible to improve the shift quality with an organized control method. A feedback control algorithm for neutral-into-gear shift, which is enabled during the inertia phase for the master clutch slip speed to track the slip speed reference, is proposed based on the power transmission structure of TH100. The performance of the feedback shift control is verified by a vehicle test which is implemented with firmware embedded TCU. As the master clutch engages along the predetermined speed trajectory, it can be concluded that the shift quality can be managed by a shift time control parameter. By extending the proposed feedback algorithm for neutral-into-gear shift to gear change and shuttle shift, it is expected that the quality of the shift can be improved.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.001	kci_detailed_000118.xml
ART002080091	oai_dc	Surface Texturing에 의한 유압부품의 마찰저감	Surface Texturing in Hydraulic Machine Components for Friction Reduction	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "박태조(경상대학교); 김민규(경상대학교)" ]	In hydraulic machinery, the hydraulic fluid acts primarily as working fluid and secondarily as a lubricant. Hence, the viscous friction force acting on the sliding components should be reduced to improve the mechanical efficiency. It is now well known that the surface texturing is a useful method for friction reduction. In this study, using a commercial computational fluid dynamics (CFD) code, FLUENT, the lubrication characteristics of a surface textured slider bearing under high boundary pressure difference is studied. The streamlines, velocity profiles, pressure distributions, load capacity, friction force and leakage flowrate are highly affected by the film thickness ratio and the textured region. Partial texturing at the inlet region of the inclined slider bearing can reduce both friction force and leakage flowrate than in the untextured case. The present results can be used to improve the lubrication characteristics of hydraulic machinery.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.027	kci_detailed_000118.xml
ART002080086	oai_dc	평행주차를 위한 자동 조향 제어시스템 개발 및 성능평가	Development and Evaluation of Automatic Steering System for Parallel Parking	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이대현(충남대학교); 김용주(충남대학교); 김태형(LG전자); 정선옥(충남대학교); 최창현(성균관대학교)" ]	This research is conducted to develop an automatic steering system for parallel parking, and the performance of the system was evaluated by parallel parking a conventional vehicle. The automatic steering system consisted of MDPS (motor driven power steering) to control steering, ESC (electronic stability control) to acquire wheel speed, ultrasonic sensors to recognize the parking space, and a controller to communicate and handle data. The parallel parking process using the automatic steering control consisted of parking space recognition, parking path generation, and parking path tracking. The path for parallel parking was generated based on a kinematic model of a conventional vehicle, and a PI controller was used to control the steering angle for path tracking. Parallel parking using the automatic steering control was conducted according to vehicle speed conditions. The results show that the errors on the x-axis and y-axis were below 0.54 m and 0.14 m, respectively, and the error on the steering angle was less than 1°. Therefore, it is possible to implement parallel parking using an automatic steering control system for conventional vehicles.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.018	kci_detailed_000118.xml
ART002080081	oai_dc	e-4WD 시스템 개발	Development of electric Four Wheel Drive System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조희영(현대자동차 연구개발본부)" ]	e-4WD(Electric-4WD) system is a 4WD(4-Wheel Drive) System that can transform a car into a Hybrid System. e-4WD consists of a Motor, Inverter, Speed reducer and Clutch. The Motor, Speed reducer and Clutch are installed on the rear sub-frame as a chassis module type. The inverter is installed separately. Compared to a mechanical 4WD, the e-4WD system has many advantages. For example, the reduced number of drivetrain components makes better use of the space. Driving with a motor only at low speed improves fuel economy and reduces exhaust gas. Engine downsizing is available because the motor assists the engine. The performance of a conventional HEV(Hybrid Electric Vehicle) system can also be maintained. This paper proposes the specifications of components and the control logic for an e-4WD System. And the effect of the e-4WD system is proven using a test vehicle equipped with components under various test conditions.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.010	kci_detailed_000118.xml
ART002084799	oai_dc	서보밸브 스풀-슬리브 형상공차가 압력 정특성에 미치는 영향 연구	Effect of Spool-Sleeve Geometry on Static Pressure Characteristics of Servo Valves	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 손성회(금오공과대학교 기계시스템공학과); 함영복(한국기계연구원)" ]	This study studied how the clearance, overlap and mismatch errors of spool-sleeve affect the static pressure characteristics of a servo valve. A computer simulation model was established as a direct acting servo valve and a series of simulations was conducted for various values of clearance, overlap and mismatch errors. Pressure gain decreased as the clearance increased. The overlap also affects the pressure gain and was similar to the effect of clearance. Asymmetry of the pressure plot got worse and worse as the mismatch error increased.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.034	kci_detailed_000118.xml
ART002084815	oai_dc	굴삭기의 버킷 끝단 위치인식에 관한 연구	A Study on Position Recognition of Bucket Tip for Excavator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김재훈(두산인프라코어); 배종호(두산인프라코어); 정우용(두산인프라코어)" ]	The accurate calculation of bucket tip position has a large influence on showing the motion of an excavator on the display device of the excavator and controlling the excavator automatically. It is generally known that Inertial Measurement Unit (IMU) sensors are more accurate than accelerometer-based sensors while the boom, arm or bucket moves because additional forces beyond gravity add additional acceleration to the sensors. To prove the accuracy difference between the two types of sensors, a position recognition system using an accelerometer-based sensor and an IMU sensor is implemented on the excavator. The experimental results show that the system using the IMU sensor significantly reduces the position recognition error while bucket moves and additional force beyond gravity exists.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.049	kci_detailed_000118.xml
ART002084646	oai_dc	압력센서 개발을 한 탄소 나노 튜 기반 지능형 복합소재 왜 특성 연구	A Study on Piezoresistive Characteristics of Smart Nano Composites based on Carbon Nanotubes for a Novel Pressure Sensor	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성용(부경대학교); 김현호(부경대학교); 최백규(부경대학교 기계설계공학과); 강인혁(부경대학교 기계설계공학과); 이일영(부경대학교); 강인필(부경대학교)" ]	This paper presents a preliminary study on the pressure sensing characteristics of smart nano composites made of MWCNT (multi-walled carbon nanotube) to develop a novel pressure sensor. We fabricated the composite pressure sensor by using a solution casting process. Made of carbon smart nano composites, the sensor works by means of piezoresistivity under pressure. We built a signal processing system similar to a conventional strain gage system. The sensor voltage outputs during the experiment for the pressure sensor and the resistance changes of the MWCNT as well as the epoxy based on the smart nano composite under static pressure were fairly stable and showed quite consistent responses under lab level tests. We confirmed that the response time characteristics of MWCNT nano composites with epoxy were faster than the MWCNT/EPDM sensor under static loads.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2016.13.1.043	kci_detailed_000118.xml
ART001958309	oai_dc	전기 인버터 구동 수압 피스톤 펌프 시스템의 효율 성능에 관한 실험적 연구	An Experimental Study on the Efficiency of the Water Hydraulic Piston Pump System driven by an Electric Inverter	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 함영복(한국기계연구원); 박준형(휘닉스 PED 기술연구소)" ]	A water hydraulic pump is likely to have serious problems of high leakage, friction and low energy efficiency. A water hydraulic pump has commonly a fixed displacement type and its outlet flow is adjusted by controlling rotation speed of the pump, which can be implemented by using an electric inverter. This study aims to investigate energy efficiency of the water hydraulic pump system which is driven by an electric inverter. The study is based on the experimental results. The pump which is used in the study shows relatively good efficiency and low leakage, low friction as well. The reasons for the good performance of pump is also investigated.	기계공학	null		kci_detailed_000118.xml
ART001959268	oai_dc	초저온 볼밸브의 열 응력 및 유동해석	Thermal stress and Flow Analysis of a Cryogenic Ball Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원); 이원희(한국기계연구원); 김현섭((주)싱크루트)" ]	The high pressure cryogenic ball valve is used to transfer the liquefied natural gas which temperature is -196℃, supplied pressure is 168kgf/㎠. In the present work, the temperature distribution and thermal deformation is calculated numerically. The CAE and CFD methods are useful to predict the thermal matter and the inner flow field of high pressure cryogenic ball valve. For this reason, to optimum design of the cryogenic ball valve, the theological behavior of the supplied LNG in a cryogenic valve has been studied. The governing equations are discredited and solved numerically by the finite-volume method and finite-element method. In this study, we designed the high pressure cryogenic ball valve that accomplishes zero leakage by elastic seal at normal temperature and metal seal at high temperature.	기계공학	null		kci_detailed_000118.xml
ART001959307	oai_dc	자동변속기용 비례제어 솔레노이드밸브 성능시험기 개발	A Development of Proportional Control Solenoid Valve Performance Tester for Automatic Transmission	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교); 이근호(한국기계연구원)" ]	The proportional control solenoid valves as well as the PWM solenoid valves operated by electric signal play an important role in the hydraulic system for automatic transmissions to improve the shift quality. However it is not generally available for the performance date because most of the automotive parts manufacturer don't release the specific test results, especially dynamic performance that is essential to design a shift control algorithm.	기계공학	null		kci_detailed_000118.xml
ART001959273	oai_dc	마이크로 솔레노이드의 해석 및 개발	Analysis and Design of Micro Solenoid	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동수(한국기계연구원 정보장비연구센터)" ]	Recently, the on-off solenoid valves have been focused on core technology in the fields of the production line of semi-conductor chips and the micro fluid chips for bio-medical applications. A key characteristics for on-off solenoid valve, operated by compressed air, are high speed response and great repeatability. Indeed, it is also important to keep the pressure on the cross-sectional area of the poppet to be constant regardless of the fluctuation of the pressure exerted on the ports. In this study, we have designed and analysed the high-speed and high flow rate on-off solenoid valve using the analogy of equivalent magnetic circuit and Finite Element Method(FEM) respectively. In case of poppet, flow characteristics was analyzed by the variation of poppet and it was able to display flow field by changing the location of the poppet. Also, we verified possibility of the design through the static and dynamic pressure and the 3D simulation using distribution curve of the force by working the front poppet.	기계공학	null		kci_detailed_000118.xml
ART001995341	oai_dc	다운더홀(DTH) 해머의 모델링 및 실험	Modelling and Test of Down-the-Hole Hammer	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "황운규(에버다임 선행개발팀)" ]	Research and development of mineral resource related products has progressed with the increased need to develop mineral resources. The DTH hammer is one a resultant product. However, due to particular work conditions of underground drilling, it is difficult to obtain direct data on the DTH Hammer. A DTH drill rig requires a lot of money and time for actual testing. This thesis aimed to resolve this problem by using CAE. First, the structure of the DTH hammer and the movement was analyzed. Next, a standard model based on simulation was proposed and then experimentation and comparison verification was conducted. In addition, the verified models were applied to products of various sizes, and the models used in simulation were compared by conducting field tests.	기계공학	null		kci_detailed_000118.xml
ART001995332	oai_dc	파랑의 수평운동을 이용한 파력발전장치 개발	Development of Wave Power Generator using Horizontal Motions of the Wave	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "황성수(전남대학교); 박일흠(전남대학교); 이동수(SEA TECH R&D Co.,); 양경욱(전남대학교)" ]	In this study, we suggested the wave power generator using horizontal motions of the wave for use in the coastal sea. The length of the horizontal movement of the wave in the vicinity of the sea surface is larger than the length of the vertical reciprocating movement of the wave, hence the proposed device has a wave power transmission plate. In addition, because the motion of the wave is maximum to the sea surface, by arranging the buoyancy tanks at the top of the wave power transmission plate, it is always capable of vertical movement in accordance with the sea surface. To confirm the usefulness of the proposed wave power generator, we constructed a mathematical model of the wave power generator and carried out simulation using bondgraph. Furthermore, the efficiency was verified by measuring the degree of electrical energy production through a preliminary experiment.	기계공학	null		kci_detailed_000118.xml
ART001995338	oai_dc	저속에서 피스톤 슈 내부 보조 링의 윤활 효과 분석	Investigation of the Tribological Effects of the Auxiliary Inner Ring for Piston Shoes at Low Speeds	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 김종혁(한국항공대학교); 홍예선(한국항공대학교); 김병곤(유원산업); 문진삼(유원산업); 문준혁(유원산업)" ]	In order to design a swash plate type pump for electro-hydrostatic actuators the performance of the hydrostatic piston shoe bearings in the low speed range needs to be examined, since the pump operates frequently at low speeds, compensating for position control errors as a control element. As a common practice, piston shoes are equipped with inner rings as an auxiliary element to enhance their tribological performance. In this paper, the effects of the inner rings of the piston shoes on the frictional loss and leakage flow rate were investigated, where three piston shoe models, with different inner ring shapes and different inlet orifice sizes, were integrated. The test results showed that a large inner ring and small inlet orifice were advantageous for reducing both the frictional loss and leakage flow rate; this could also be confirmed by computational analyses.	기계공학	null		kci_detailed_000118.xml
ART001995329	oai_dc	정유압구동기(EHA)의 모델링과 제어기 설계	Modeling and Controller Design of an Electro-Hydrostatic Actuator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "허준영(한국기술교육대학교); 김현호(부경대학교); 이일영(부경대학교)" ]	Recently, the Electro-Hydrostatic Actuator(EHA) has been developed as a result of research on energy saving. EHA is usually composed of a direct driven pump from an electric motor and is available to control cylinder displacement or velocity with high efficiency. In addition, it has the advantage of compactness, minimum leakage and availability of decentralized control. In this study, an EHA system was designed to decrease the path tracking error and manufactured for test. The linearization method provided in AMESim software was used to derive the model of EHA system. The derived model was applied to design the PI-D controller to effectively overcome the disturbance. The effectiveness of this controller was verified by further testing.	기계공학	null		kci_detailed_000118.xml
ART001995345	oai_dc	메인 컨트롤밸브의 해석모델 개발 및 검증	Development and Verification of Analytical Model of a Main Control Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동명(가천대학교); 이정민(창원대학교); 정원지(창원대학교); 장주섭(가천대학교)" ]	In order to control the actuators of hydraulic machinery such as excavators, various control valves are typically assembled in a single block. Such a control block is called a main control valve(MCV). In this paper, we analyzed the working principle and the particular purpose of the design of all valves included in the MCV system. To Examine the reliability of the analysis model, the pressure drop of the MCV at each port was measured. The authors developed an analytical model of the control valve(main spool, load poppet, pressure relief, make up, and regeneration). The authors considered the notch shape of the spool while developing the analytical models of the main spool valve. Most importantly, at the stage before the analysis model was applied in the design tuning, the reliability was ensured by comparing the analysis results with the test results. This paper showed a process of developing an analysis model that can be utilized in the design and tuning stages.	기계공학	null		kci_detailed_000118.xml
ART001995335	oai_dc	AC서보모터-볼스크루 구동 사출장치의 힘 동기제어	Force Synchronizing Control for AC Servomotor-Ball Screw Driven Injection Unit	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조승호(홍익대학교)" ]	This paper focuses on the issue of force synchronizing control for the injection servomechanism of injection molding machines. Prior to the controller design, a virtual design model was developed for the injection mechanism with an AC servomotor-ball screw. A synchronizing controller is designed and combined with the PID control to accommodate the mismatches between the real plant and the linear model plant used. Due to the plant uncertainty, the stiffness and the damping of the mechanism were considered. From the tracking control simulations based on the virtual design model, it is shown that a significant reduction in force synchronizing error is achieved through the use of a proposed control scheme.	기계공학	null		kci_detailed_000118.xml
ART001995340	oai_dc	Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System	Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "레광환(울산대학교); 정영만(울산대학교); 웨치탄(울산대학교); 양순용(울산대학교)" ]	Excavators are versatile earthmoving equipment that are used in civil engineering, hydraulic engineering, grading and landscaping, pipeline construction and mining. Effective operator training is essential to ensure safe and efficient operating of the machine. The virtual reality excavator based on simulation using conventional large size monitors is limited by the inability to provide a realistic real world training experience. We proposed a flexible observation method with a head tracking system to improve user feeling and sensation when operating a virtual reality excavator. First, an excavation simulator is designed by combining an excavator SimMechanics model and the virtual world. Second, a head mounted display (HMD) device is presented to replace the cumbersome large screens. Moreover, an Inertial Measurement Unit (IMU) sensor is mounted to the HMD for tracking the movement of the operator's head. These signals consequently change the virtual viewpoint of the virtual reality excavator. Simulation results were used to analyze the performance of the proposed system.	기계공학	null		kci_detailed_000118.xml
ART001908755	oai_dc	Modeling and Performance Investigation of Forklift Transmission Control Valve System	Modeling and Performance Investigation of Forklift Transmission Control Valve System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "딩광청(울산대학교); 안경관(울산대학교); 윤장원(ms정밀)" ]	In forklifts, the machine performance is largely depended on the transmission performance. The aim of this paper is to develop a complete model of transmission control valve (TMV) system of a typical forklift using AMESim simulation tool. By using the developed TMV model, it becomes easy to investigate the system concept, working principle, and performance. In addition, an optimization on the TMV structure can be achieved by using this model with tunable parameters. Simulations have been carried out in a comparison with the actual experiments to verify the model.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.001	kci_detailed_000118.xml
ART001908756	oai_dc	A Ship Berthing System Design by Cooperating with Tugboats and Dampers	A Ship Berthing System Design by Cooperating with Tugboats and Dampers	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "안민트란(부경대학교 대학원 제어기계공학과); 지상원(부경대학교); 김영복(부경대학교)" ]	Everyday about 90% of cargos are delivered by ships, and thousands of vessels enter and depart the international container harbors such as Shanghai, Singapore, Hong Kong, Busan, Rotterdam, etc. Maneuvering at harbor is known as the most sophisticated and difficult procedure, because the effectiveness of actuators during low speed berthing is reduced. In this paper, a new berthing method is discussed. Tugboats are combined with damper systems to ensure safe berthing. A mathematical model describing the interaction between unactuated ship, tugboats and damper systems is presented. An optimal controller is designed to maneuver the ship without oscillation and overshoot. MCL (Marine Cybernetics Lab) model ship is used to evaluate the efficiency of the proposed approach through MatLab simulation.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.007	kci_detailed_000118.xml
ART001908757	oai_dc	드리프터의 유압시스템 해석모델 개발 및 신뢰성 검토	Development of drifter’s hydraulic system model and its validation	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "노대경(가천대학교); 장주섭(가천대학교); 김흥섭(한국기계연구원); 박승현((주)필엔지니어링); 서자호(한국기계연구원)" ]	The goal of this study drifter is to understand the operating mechanism of a drifter and to suggest a reliable analysis model which can be used for evaluating the drifter’s performance from the viewpoint of impact frequency and energy. For this, the working principle of drifter and functions of its main components were analyzed, and a simulation model was developed based on the analysis. The model was validated using experimental tests on a test-bench. A comparative study of simulation and experimental results indicated that the suggested model accurately represents the real drifter system in terms of impact frequency and impact energy per blow.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.014	kci_detailed_000118.xml
ART001908758	oai_dc	A Study of Stability for Field Robot using Energy Stability Level Method	A Study of Stability for Field Robot using Energy Stability Level Method	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "웨치탄(울산대학교); 레광환(울산대학교); 정영만(울산대학교); 양순용(울산대학교)" ]	In this research, the energy stability level method is used for examining the stable state of Field Robot under effects of swing motion, at particular postures of manipulator, and terrain conditions. The energy stability level is calculated by using the dynamic models of Field Robot, subjected to the concept of equilibrium plane and support boundary. The results, simulated by using computing program for estimating the potential overturning of Field Robot, supply useful predictions of stability analysis for designers and operators.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.022	kci_detailed_000118.xml
ART001908759	oai_dc	Development of a Multi-Absorbing Wave Energy Converter using Pressure Coupling Principle	Development of a Multi-Absorbing Wave Energy Converter using Pressure Coupling Principle	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "도황팅(울산대학교); 누엔밍치(울산대학교); 판콩빙(울산대학교); 이세영(울산대학교); 박형규(울산대학교); 안경관(울산대학교)" ]	This paper proposes a multi absorbing wave energy converter design, in which a hydrostatic transmission is used to transfer wave energy to electric energy. The most important feature of this system is its combination of the pressure coupling principle with the use of a hydraulic accumulator to eliminate the effects of wave power fluctuation; this maintains a constant speed of the hydraulic motor. Tilt motion of a floating buoy was employed as the power take-off mechanism. Furthermore, a PID controller was designed to carry out the speed control of the hydraulic motor. The design offers some advantages such as extending the life of the hydraulic components, increasing the amount of energy harvested, and stabilizing the output speed.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.031	kci_detailed_000118.xml
ART001908760	oai_dc	HST 중립밸브의 해석모델 개발 및 설계변수 민감도 분석	Analysis Model Development and Sensitivity Analysis on Design Parameters of the Neutral Valve for HST	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김동명(가천대학교); 장주섭(가천대학교); 김수철(LS엠트론)" ]	The neutral valve for controlling the HST is one of the important valves for the vehicle control. Neutral valve takes a role of blocking or transmitting power to the vehicle. The operating principle of the neutral valve was developed through the analysis model. We also investigated the logical validity by analyzing the results of the analysis model. The analysis model was developed by using SimulationX witch is commercial software. The number of holes in the piston was selected as a variable initial compression of the spring, and the magnitude of the pressure pulsations and the diameter of the orifice for the sensitivity analysis were performed to design sensitivity analysis of the neutral valve.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.041	kci_detailed_000118.xml
ART001908761	oai_dc	자동변속기 클러치 충전제어 파라미터의 실험적 특성분석	Experimental Analysis of Clutch-Fill Parameters for Automatic Transmission	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교); 박동훈(시스톤 테크놀로지스)" ]	Clutches are an integral part of the automatic transmission for changing gears. Modern automatic transmissions make extensive use of wet multiple-disc clutches employing hydraulic actuation mechanism with electronic control. Although nowadays, highly advanced shifting algorithm implements the superior shift quality and transmission efficiency, its performance should be based on smooth, reliable engagement with a reasonably durable friction material as well as stable clutch piston dynamics. Particularly, clutch filling control is the crucial part of shifting process because only the open-loop control is available due to the lack of measurement. In this paper, the effect of clutch-fill control parameters on clutch piston dynamics is experimentally investigated by using clutch piston test equipment which enables the clutch piston to actuate similar to real shifting conditions. The experimental analysis results can be expected to be utilized for the calibration of proportional solenoid valve as reference current profile data in vehicle test.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2014.11.3.047	kci_detailed_000118.xml
ART002139524	oai_dc	제어밸브의 유량특성에 따른 에어스프링의 성능 변화	Effect of Control Valve Flow Rates Characteristics on the Performance of an Air Spring	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "한승훈(부경대학교); 장지성(부경대학교); 지상원(부경대학교 기계시스템공학과)" ]	This study describes the effect of the critical pressure ratio of a control valve on the performance of an air spring system composed of an air spring, auxiliary chamber, control valve and mass in order to suggest a more efficient design for an air spring system. The critical pressure ratio of the control valve is assumed to have a fixed value, but the critical pressure ratio of the control valve is known to have various values between 0.05 and 0.6, and the effect of the variation of the critical pressure ratio on the performance of the air spring system has not yet been reported. The analysis derives nonlinear and linear governing equations of the air spring system, including the critical pressure ratio of the control valve. This simulation study is presented to show that the impedance and transmissibility characteristics of the air spring system change due to variations in the critical pressure ratio of the control valve as well as its sonic conductance. As a result, the critical pressure ratio of the control valve should be maintained as large as possible to improve the vibration isolation characteristics of the air spring system.	기계공학	null		kci_detailed_000118.xml
ART002139482	oai_dc	상온기체 블로우다운 방식을 사용한 유도무기용 유압식 구동장치의 공압부에 대한 모델링 및 시뮬레이션	Modeling and Simulation of the Pneumatic Part in a Cold Gas Blow-Down Type Hydraulic Actuation System for a Missile	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "박희승(국방과학연구소(대전))" ]	A cold gas blow-down hydraulic actuation system is widely used in missiles that require an actuation system with a fast response time under a limited space with a short operating time and large loads on the actuators. The system consists of a pneumatic part that supplies the regulated high-pressure gas to a reservoir, and a hydraulic part that supplies pressurized hydraulic oil to the actuators by the pressurized gas in the reservoir. This paper proposes a mathematical model to analyze and simulate the pneumatic part of an actuation system that supplies the operating power to the actuators. The mathematical model is based on the ideal gas equation and also considers the models for heat transfer. The model is applied to the pressure vessel and the gas part of the reservoir, and the model for the pneumatic part is established by connecting the two models for the parts. The model is validated through a comparison of the simulation results with the experimental results. The comparison shows that the suggested model could be useful in the design of the pneumatic part of a cold gas blow-down type hydraulic actuation system.	기계공학	null		kci_detailed_000118.xml
ART002142402	oai_dc	양방향 구동 사판식 액시얼 피스톤 펌프의 밸브 플레이트 노치 설계에 관한 연구	A Study on Design of Notches in Valve Plate of Swash Plate Type Axial Piston Pumps Operated Bi-directionally	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "최세령(부경대학교); 이일영(부경대학교); 한성민(세원셀론텍(주)); 신정우(세원셀론텍(주))" ]	Flow and pressure ripple in swash plate type piston pumps is largely dependent on the design of notches(silencing grooves) in the valve plate. In uni-directional pumps, the basic design concept for notches in the valve plate could be said to be established. It is easily deduced that the design concept for notches in uni-directional pumps can not be simply applied to bi-directional pumps requested for EHA(electric hydrostatic actuators). To carry out systematic research on technological issues regarding notch applications to bi-directional piston pumps, five notch designs are devised. The effects of the notch designs on the characteristics of the pump are investigated by numerical simulations and experiments. Through this study, basic concepts about notch design for bi-directional piston pumps are suggested.	기계공학	null		kci_detailed_000118.xml
ART002141513	oai_dc	비례적분+이중적분 제어기를 이용한 정상상태 응답 개선	Improvement of Steady State Response Using PI+Double Integral Controller	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교)" ]	The performance characteristics of a dynamic control system are evaluated according to the transient and steady-state responses. The transient performance is the controllability of the output for the tracking of the reference or the ability to reduce or reject the effects of unwanted disturbances; alternatively, the steady-state performance is represented by the magnitude of the control error at the steady state. As the effects of the two performances on each other are reciprocal, a controller design that shows a zero steady-state error for the ramp input is uncommon because of the challenge regarding the achievement of an acceptable transient response. This paper proposes a PI+double-integral controller for the elimination of the steady-state error for the ramp input while a sound transient performance is maintained. The control-gain design procedure is described by the second-order response for the step input and the response of the error dynamics for the ramp input. The PI+double-integral controller is designed for the first-order transfer function that is derived from a system identification with the open-loop experiment data of the dc-motor. The simple structure of the proposed controller enables the adoption of a low-end microcontroller for the implementation of a real-time control. The experiment results show that the control performance is as effective as that of the simulation analysis for the operating point of linear system; furthermore, the PI+double-integral controller can be conveniently applied to the control system, which is desirable for the improvement of the steady-state error.	기계공학	null		kci_detailed_000118.xml
ART002141508	oai_dc	근궤적과 수동 조정에 의한 직접 구동형 서보밸브의 PID 제어기 및 미분피드백 이득 설계	PID Controller and Derivative-feedback Gain Design of the Direct-drive Servo Valve Using the Root Locus and Manual Tuning	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성래(건양대학교)" ]	The direct-drive servo valve(DDV) is a kind of one-stage valve because the main spool valve is directly driven by the dc motor. Since the DDV structure is simple, it is less expensive, more reliable, and offers a reduced internal leakage and a reduced sensitivity to fluid contamination. The control system of the DDV is highly nonlinear due to a current limiter, a voltage limiter, and the flow-force effect on the spool motion. The shape of the step response of the DDV-control system varies considerably according to the magnitudes of the step input and the load pressure. The system-design requirements mean that the overshoots should be less than 20%, and the errors at 0.02s should be less than 2%, regardless of the reference-step input sizes of 1V and 5V and the load-pressure magnitudes of 0MPa and 20.7MPa. To satisfy the system-design requirements, the PID-controller parameters of , and , and the derivative-feedback gain of are designed using the root locus and manual tuning.	기계공학	null		kci_detailed_000118.xml
ART002141529	oai_dc	이중 EHA의 제어 특성 개선	Control-performance Improvement of Dual EHAs	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 홍예선(한국항공대학교)" ]	For this paper, the position-control performances of dual EHA(electro-hydrostatic actuator) systems were investigated according to two cases wherein the double-rod- and single-rod-type hydraulic cylinders were combined. Since the control performance is significantly dependent on the load conditions including external forces such as the inertia load, it is proposed here that the two sub-EHAs are driven by separate position and force controllers, instead of two identical position controllers. According to the simulation results, the best performance was achieved by the position-controlled single-rod-type EHA that was combined with a force-controlled double-rod-type EHA. As the force-controlled double-rod-type EHA compensated for the external loads on the position-controlled single-rod-type EHA, the position-control performance was not influenced by external forces including the inertia load. In addition, the position-controlled single-rod-type EHA contributed to the enhancement of the damping ratio by absorbing the pressure peaks through its internal accumulator. Due to the symmetrical piston areas, the double-rod-type EHA is more suitable for force control than the single-rod- type EHA.	기계공학	null		kci_detailed_000118.xml
ART002142420	oai_dc	비례제어 솔레노이드 액추에이터의 응답성 향상 연구	A Study on Response Improvement of a Proportional Solenoid Actuator	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "윤소남(한국기계연구원); 함영복(한국기계연구원); 박중호(한국기계연구원)" ]	This paper presents a control method for the performance improvement of a proportional solenoid actuator using a Pulse Width Modulation (PWM) signal. It is very difficult to obtain excellent response performance from a proportional solenoid actuator using a simple proportional controller with no PWM signal or dither because the mass and structure of a proportional solenoid actuator changes according to the application target, friction force in the proportional solenoid tube, operating force and displacement range. To solve the above problems, first, a controller with a PWM function for experimenting with attraction force characteristics was designed and manufactured. Secondly, an experimental setup for solenoid performance measurement with a force sensor and a displacement sensor was also manufactured. The attraction force characteristics according to the frequency and duty ratio variations of a PWM signal were tested and the relationships among the frequency, duty ratio, plunger mass and friction characteristics were analyzed. Finally, response characteristics improvements for proportional solenoid actuators are discussed.	기계공학	null		kci_detailed_000118.xml
ART002142432	oai_dc	건설기계의 에너지 효율 제고를 위한 비-하이브리드 신기술에 관한 리뷰	A Review on New Non-hybrid Technologies to Improve Energy Efficiency of Construction Machineries	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조중선(창원대학교)" ]	New non-hybrid approaches to improve energy efficiency of construction machineries are reviewed in this paper. Hydraulic systems are classified into four classes according to Backé’s classification and commercially promising new technologies are carefully chosen in each class. IMV, 3-Line CPR, Closed Circuit Displacement Control of Differential Cylinder, and Throttle-less Secondary Control are chosen as representative non-hybrid new technologies. Key principle of each technology is explained and representative references which run through each technology are selected. Advantages and weaknesses of each technology are discussed and compared from the view point of construction machinery manufacturers.	기계공학	null		kci_detailed_000118.xml
ART002110129	oai_dc	2-방향 카트리지 밸브 기반 로직회로에 의한 사출성형기의 형체력 제어	Clamping force control of injection molding machine using 2-way cartridge valve based logic circuit	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조승호(홍익대학교)" ]	The present study deals with the issue of clamping force control of an injection molding machine using 2-way cartridge valve based logic circuit. The operating principle for the cartridge valve is described with its construction and static opening behavior. Basic module circuits are designed first and analysed according to the basic functions. Then they are combined with a virtual design model for the clamping mechanism to simulate the control performance of the overall system. The backlash inherent in the mechanism is considered while evaluating the time-delay in the process of clamping force build-up. The effects of a couple of design parameters in backlash, i.e. , interval and stiffness have been demonstrated in the time-domain.	기계공학	null		kci_detailed_000118.xml
ART002109839	oai_dc	지게차의 주관적 음질평가와 Zwicker 음질지수의 상관관계 및 전달경로분석법(OTPA)을 활용한 음질 기여도 분석	A Study on Contribution Analysis using Operational Transfer Path Analysis based on the Correlation between Subjective Evaluation and Zwicker's Sound Quality Index for Sound Quality of Forklifts	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김범수(현대중공업 건설장비 신뢰성평가부); 양순용(울산대학교)" ]	Recently, drivers have begun to regard comfort in the cabin as one of the most important factors in construction equipment like forklifts. Accordingly, it has become more important to design a forklift cabin with a better sound quality as well as lower sound level, which can make a driver more comfortable. In this paper, the correlation between subjective evaluation and Zwicker’s sound quality index was analyzed through a blind test by a few workers in forklifts and other construction equipment in several countries. Correlation analysis showed that Loudness and Sharpness were ranked in sequence, and tendencies were different from country to country. Also, contribution analysis for Loudness and Sharpness using operational transfer path analysis (OTPA), which is widely used in the field of noise, vibration, and harshness (NVH), was performed. However, Loudness and Sharpness cannot be used with OTPA directly because there are no linear relationships between the sources and receivers. In this paper, both are calculated by applying the DIN 45631 method with a contribution rate (%) of 1/3 Octave Sound Pressure Level by OTPA method in addition to considering spectral masking.	기계공학	null		kci_detailed_000118.xml
ART002109862	oai_dc	인공 신경회로망을 이용한 전자비례 감압밸브의 솔레노이드 형상 최적화	Optimization of Design Parameters of a EPPR Valve Solenoid using Artificial Neural Network	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "윤주호(울산대학교); 웬민냣(울산대); 이현수(울산대학교); 윤장원(울산대 기계공학부 유공압 및 기계지능 연구실); 김당주((주) 대호하이드로릭); 이동원((주) 대호하이드로릭); 안경관(울산대학교)" ]	Unlike the commonly used On/Off solenoid, constant attraction force which is independent of plunger displacement is a considerably important characteristic to proportional solenoid of the EPPR Valve. Attraction force uniformity is mainly affected by the internal shape design parameters. Due to a number of shape design parameters, the optimal parameter values are very complex and time consuming to find by trial and error method. Much research has been conducted or are still in progress to find the optimal parameter values by applying various optimization techniques like Genetic Algorithm, Evolution Strategy, Simulated Annealing, or the Taguchi method. In this paper, the design parameters which have primary effects on the attraction force uniformity and the average attraction force are decided by main effects analysis of Design of Experiments. Optimal parameter values are derived using finite-element analysis and a neural network model.	기계공학	null		kci_detailed_000118.xml
ART002110125	oai_dc	배관 압력을 이용한 서보밸브 정적 특성에 관한 실험적 연구	An Experimental Study on Static Characteristics of Servo Valves using Transmission Line Pressures	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 주별진(Dong Yang Industrial Co.,LTD. Top Run R&D Center, Korea); 윤소남(한국기계연구원)" ]	The conventional technique to measure the hysteresis and the null of servo valves is defined in ISO 10770-1 and based on load flow signal of the servo valve. A new technique based on the transmission line pressures is suggested in this study. The new measuring method was verified through a series of experiments. No hysteresis was observed between the spool displacement and the transmission line pressures, load pressure or each chamber pressure. Some hysteresis was observed between valve input and pressures, which was found to be the same as those of load flow and spool displacement for the valve input. By using the chamber pressures, the hysteresis and the null are easier to measure than the load pressure or differential pressure between those two chamber pressures because the chamber pressures showed sharp edges.	기계공학	null		kci_detailed_000118.xml
ART002109832	oai_dc	비대칭 이중화 EHA의 동기 제어	Synchronous Control of an Asymmetrical Dual Redundant EHA	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 홍예선(한국항공대학교)" ]	In this paper, an elementary force fighting problem was investigated. The problem is encountered when a double-rod type EHA(electro-hydrostatic actuator) is combined with a single-rod type EHA to build a redundant actuator system with synchronized motion. When the rod-side chambers of the two different types of EHAs have the same effective piston areas and are simultaneously pressurized by an external load, the two EHAs behave identically, sharing the external load equally. However, when the piston head-side chamber of the single rod type EHA, having a larger effective area than the rod-side chamber, is pressurized by the external load, an abnormal force fighting between the two EHAs occurs, unless their pump speeds are properly decoupled. In this study, the output drive forces of each EHA were obtained from the cylinder pressure signals and applied to the position control for each EHA to maintain the balance between their pump speeds. Adding minor force difference feedback loops to the position control, the force fighting phenomena could be eliminated and steady state synchronization errors were reduced. The power consumption of the pumps also could be remarkably reduced, avoiding unnecessarily high load pressures to the pumps.	기계공학	null		kci_detailed_000118.xml
ART002109838	oai_dc	농업용 트랙터의 프론트 로더 충격 저감을 위한 유압 회로의 설계 개선	Improved Design of Hydraulic Circuit of Front-end Loader for Bump Shock Reduction of an Agricultural Tractor	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조봉진(서울대학교 바이오시스템공학); 안성욱(서울대학교); 이창주(서울대); 윤영환(J&F Solution); 이수성(태성공업); 김학진(서울대학교)" ]	A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements to mechanize routine agricultural tasks. When the FEL is used with a loaded bucket, careful operation is required to maintain safety and avoid spillage when the tractor passes a bump because a change in the gravity center of the tractor due to varied loadings can affect the stability of the tractor. Use of a boom suspension system consisting of accumulators and orifice dampers can be instrumental in reducing pitching vibrations while increasing the handling performance of the FEL-mounted tractor. The objective of this research was to reduce bump shocks by adding an orifice and a flow control valve to the original hydraulic circuit composed solely of accumulators. A simulation study was performed using the SimulationX program to investigate the effects of an accumulator and an orifice-throttle damper on bump shocks. Results showed that the peak pressure on a boom cylinder and the vertical acceleration of a bucket were significantly affected by use of both an accumulator and an orifice damper. In a field test conducted with a 75-kW tractor, the peak pressure of the boom cylinder, and the root mean square (RMS) vertical acceleration of the bucket and seat were reduced by on average, 23.0, 42.2, and 44.9% respectively, as compared to those measured with the original accumulator system, showing that an improved design for the accumulator hydraulic circuit can reduce bump shocks. Further studies are needed to design a tractor suspension system that includes the effects of cabin suspension and tires as well as dynamic analysis.	기계공학	null		kci_detailed_000118.xml
ART002109841	oai_dc	보행 로봇을 위한 서보밸브 구동 유압 액추에이터의 특성 분석	A Study of Hydraulic Actuator Based On Electro Servo Valve For A Walking Robot	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조정산(한국생산기술연구원 로봇그룹)" ]	This paper describes of a mathematical and real experimental analysis for a walking robot which uses servo valve driven hydraulic actuator. Recently, many researchers are developing a walking robot based on hydraulic systems for the difficult and dangerous missions such as walking in the rough terrain and carrying a heavy load. In order to design and control a walking robot, the characteristics of the hydraulic actuators in the joint through the view point of walking such as controllability and backdrivability must be analyzed. A general mathematical model was used for analysis and proceeds to position and pressure changes characteristic of the input and backdrivability experiment. The result shows the actuator is a velocity source, had a high impedance, the output stiffness is high in contact with the rigid external force. So stand above the controller and instruments that complement the design characteristics can be seen the need to apply a hydraulic actuator in walking robot.	기계공학	null		kci_detailed_000118.xml
ART001822559	oai_dc	유압 윈치를 이용한 선박 자동 계선법	Proposition of Automatic Ship Mooring Using Hydraulic Winch	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "허정규(전남대학교); 양경욱(전남대학교)" ]	연구는 선박 계선 안정성을 확보하는 방법으로 선박의 상갑판에 위치한 유압 윈치를 이용하는 방법을제안하였으며, 제안한 선박 계선 장치를 시뮬레이션하였다. 시뮬레이션을 통하여 선박 무게의 증감이 계선 속도와 횡동요 현상에 영향을 주고, 선미 종경사가 발생했을 경우에는 선박 평행 유지와 선수 동요 현상에영향을 미치며, 계선 시점에서는 선박의 정지 마찰력영향을 고려해야 함을 밝혔다. 균등한 선박 무게의증가도 초반부의 계선력 크기에 영향을 미치지만, 선박 관성(타력)이 발생하기 시작하면 유체 저항력은상쇄된다는 것도 확인할 수 있었다. 또한, 선박 계선안정성에 크게 영향을 미치는 횡동요와 선수동요 현상은 종경사 상태에서 관성모멘트의 영향으로 심화될수 있기 때문에 초기 계선력 결정에 유의해야 할 것으로 판단된다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.014	kci_detailed_000118.xml
ART001822561	oai_dc	전기 피드백 직동형 서보 밸브에 관한 역 분석	Reverse Analysis on a Direct Dive Servo Valve with Electric	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 안희욱(금오공과대학교)" ]	본 연구에서 LVDT 스풀변위 피드백 기능을 가지는 직동형 서보 밸브에 관하여 역분석 (reverse analysis)을 수행하였으며, 주요한 결과는 다음과 같이 요약된다. 1) 스풀 복귀 스프링의 강성이 매우 높고 선형 힘모터의 전류의 수준 또한 1000mA 범위로 높다. 2) 스풀 스프링의 강성에 비교하여 스풀 질량은상대적으로 작으며 스풀질량–스프링계의 고유 주파수는 195 Hz로 매우 높다. 3) 비례⋅적분(PI) 제어 방법과 속도⋅가속도 피드백이 서보 증폭기에 적용되었다. 적분기 이득은 일반적인 PI 제어기의 적분 이득보다 훨씬 크다. 적분 이득이 매우 큰 경우에 시스템의 안정성이 떨어질 가능성이 높은데, 매우 큰 적분 이득과 시스템의 안정성을 향상시키기 위해 속도 ⋅가속도 피드백이 적용된 것으로 보인다. 4) 선형 모터의 구동 전류를 생성하는 부분에서비교적 정밀도가 떨어지는 PWM 제어방법이 사용되고 있지만 전류 피드백이 적용되고 있어서 선형 힘모터의 정밀한 전류 구동을 가능하게 한다.  ×  정도의 큰 적분기 이득은 전류 피드백 루프 안에서사용되는데, 전류 피드백 루프 전체의 전달함수는 일정한 비례이득의 비례제어로 생각할 수 있다. 즉, 단순한 전압-전류변환기로 간주 될 수 있다. 5) 선형 힘 모터는 자기 히스테리시스 특성을 가지는데, LVDT 전기 피드백은 히스테리시스 효과를보상해 줌으로써 서보 밸브의 출력 신호인 스풀 변위와 유량, 압력에서는 히스테리시스 효과를 거의 완벽하게 제거한다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.022	kci_detailed_000118.xml
ART001822572	oai_dc	직접 제어 방식을 적용한 소형 지게차 변속 시스템에 관한 연구	A Study on Applying the Direct Control Method for Small Forklift Transmission System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정영만(울산대학교); 임구(울산대학교); 양순용(울산대학교)" ]	본 논문에서는 소형지게차의 메인 컨트롤 밸브를직접방식으로 개발하고 비례제어 밸브를 통해 변속충격과 출발성능을 개선하는 연구를 하였다. 본 연구의 결과는 다음과 같다. (1) 파일럿 제어 방식의 MCV를 직접 제어 방식으로 개발하였다. (2) 비례제어 밸브를 제어 할 수 있는 임베디드 시스템을 개발하였다. (3) 변속감도와 출발성능을 개선하기 위해 입력 프로파일의 변화에 따른 Fill구간, Hold구간, Ramp구간의 실차 테스트를 수행하였다. (4) 입력 프로파일의 각 구간이 변속충격과 출발성능에 미치는 영향을 파악하였다. 향후 변속감도와 출발성능을 주관적인 느낌이 아닌 객관적인 데이터로 표현할 수 있는 연구를 수행할 예정이다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.034	kci_detailed_000118.xml
ART001822566	oai_dc	압축성유체 유량계측장치 설계 및 제작	Design and Building of Flow-rate Measurement Apparatus for Compressible Fluid	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "지상원(부경대학교); 장지성(부경대학교)" ]	공기압 구동시스템에서 밸브를 통과하는 압축공기의 유량은 중요한 설계조건으로 정확한 계측이선결되어야 한다. 그러나 ISO 6358에서 제안된 유량계측법은 많은 시간과 에너지가 소비되는 작업이며 계측정확도 확보도 용이하지 않다. 따라서, 본 연구에서는 등온용기를 이용하여 각종 밸브 및실린더, 피팅, 전달관로 등과 같은 공기압 부품의통과유량 및 누설유량을 계측 할 수 있는 계측장치를 설계하였다. 설계된 계측장치는 최대6.343[dm3/(s·bar)]의 음속컨덕턴스를 계측 할 수있도록 설계하여 제작하였다. 제작된 계측장치의 등온성능 확인을 위하여 최대유량을 인가하여 용기내부 온도변화를 계측한 결과, 용기내부 온도변화량이 4[K]미만으로 억제되고 있음을 확인하였다. 또한, 계측장치의 유량방출 경로상에부착된 밸브와 피팅 및 관로 등에 의해 본 계측장비의 임계압력비는 0.35로 나타났고, 음속컨덕턴스는7.320 [dm3/(s·bar)]로 나타났으므로, 본 계측장비로설계목표치인 최대 음속컨덕턴스 6.343[dm3/(s·bar) ] 을 계측 할 수 있음을 확인하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.029	kci_detailed_000118.xml
ART001822550	oai_dc	연비 평가를 위한 6속 DCT기반 HEV 성능 시뮬레이터의 개발	Development of Performance Simulator for 6-speed DCT-based Hybrid Electric Vehicle to Evaluate the Fuel Economy	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "백진주(성균관대학교); 이용관(성균관대학교); 박진현(성균관대학교); 한관수(성균관대학교); 황성호(성균관대학교)" ]	6속 DCT기반 디젤 HEV 모델링을 구현하였으며, 동일한 디젤 HEV에 변속기를 AT와 DCT로 변경하여 FTP75와 NYCC 주행모드에 따른 SOC 및 연비 결과를 비교하였다. 이를 통해 얻어진 결론은 다음과같다. - 6속 DCT기반 HEV 성능 시뮬레이터를 개발하였으며, FTP75와 NYCC 주행모드를 통해 시뮬레이션 결과를 확인하였다. - 디젤 HEV에 변속기로 AT와 DCT를 각각 장착한 차량 모델링을 수행하였으며, 시뮬레이션을 통해얻어진 SOC 변화량과 연비를 비교하였다. - AT기반 디젤 HEV의 경우, 토크 컨버터로 인한동력손실로 인해 DCT기반 디젤 HEV의 SOC 및 연비 효율이 약 12% 정도 향상됨을 확인하였다. - 현재 AT모델은 락업(lockup) 상태를 고려하지않았으며, 이를 고려한 AT 모델로 보완하여 비교한다면 연비효율 향상 정도가 현재의 결과보다는 다소감소될 것으로 예측된다. 향후, AT 모델링 보완과 DCT 모델에 클러치 액추에이터 모델을 추가함으로써 액추에이터 제어에따른 클러치 제어 성능을 확인할 예정이다. 이를 통해 본 성능 시뮬레이터는 6속 DCT기반 HEV의 최적화된 연비 및 동력 성능 알고리즘 개발에 효과적으로 활용될 수 있을 것이다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.001	kci_detailed_000118.xml
ART001822555	oai_dc	선진사 트랙터 자동변속기 설계 분석	Automatic Transmission Design Analysis of the Tractor from Advanced Company	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교)" ]	본 연구에서는 100마력급 이상 트랙터에 적용되는Kuboda와 John Deere사의 24단 자동변속기를 대상으로 정비 매뉴얼에서 제공되는 자료를 토대로 기어열, 유압제어시스템, 변속제어기의 설계를 분석하였다. 향후에는 TCU 성능분석기를 개발하고 이를 활용하여 실차시험을 통해서 보다 상세한 작동 및 제어성능을 분석한 후 독자모델 자동변속기 개발에 반영할 예정이다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.4.007	kci_detailed_000118.xml
ART001748011	oai_dc	사판식 유압 피스톤 펌프의 슬리퍼 정압베어링면 형상에 관한 이론해석	Theoretical Analysis of the Slipper Hydrostatic Bearing Shape in the Swash Plate Type Axial Piston Pump	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조인성(전북대학교)" ]	이상과 같이 사판식 유압 피스톤 펌프의 슬리퍼 정압베어링 형상에 따른 이론해석을 통해 다음과 같은결론을 얻었다. 1) 슬리퍼의 랜드 부분과 환상 포켓부의 압력분포와 부하용량은 슬리퍼 형상에 의존하며, 모델 A가 가장 크게 나타났으며, 압력분포에 의해 계산된 부하용량은 모델 A가 가장 크게 나타났다. 2) 슬리퍼의 형상에 따라 누설유량, 유막두께 및동력손실 등이 좌우됨을 확인할 수 있었으며, 유막두께가 6 미만의 경우에는 모델 C가, 그 이상의 유막두께를 갖는 구간에서는 모델 B가 동력손실이 가장 작음을 확인하였다. 3) 점도와 유막두께의 변화에 따른 누설과 부하용량 측면에서는 모델 A가 누설은 적고, 부하용량은 크게 나와 가장 우수함을 확인할 수 있었다. 따라서 슬리퍼의 형상에 따라 윤활과 성능특성이결정됨을 확인할 수 있었고, 사용조건 및 요구조건에따른 최적의 성능을 얻을 수 있는 슬리퍼의 형상을설계하기 위한 기초 자료로 활용할 수 있을 것으로여겨진다.	기계공학	null		kci_detailed_000118.xml
ART001748023	oai_dc	A Study of Wind Energy Conversion System by a Secondary Control Hydrostatic Transmission	A Study of Wind Energy Conversion System by a Secondary Control Hydrostatic Transmission	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "안경관(울산대학교); 도황팅(울산대학교)" ]	Wind energy has been more and more important and contributive in the energy utilization of the world. This paper proposed a novel method for Wind Energy Conversion System (WECS), in which a secondary control hydrostatic transmission (SC-HST) with two hydraulic accumulators, were employed for wind energy conversion system. This approach can absorb the excessive power of turbine, keep the generator from over-speed and maintain the speed of generator in low speed of turbine. A PID controller was designed for speed control to track a predefined speed. The simulation results indicated that the speed of the generator was ensured with the relative error less than 2%; and the efficiency of the proposed system was 70.4%.	기계공학	null		kci_detailed_000118.xml
ART001747995	oai_dc	마찰력 보상을 고려한 공기압 실린더의 위치제어	Position Control of a Pneumatic Cylinder Considering Friction	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김도태(경일대학교); 장중걸(경일대학교)" ]	본 연구에서는 마찰력을 고려한 공기압 실린더의위치제어 성능을 향상시키기 위해, H∞ 제어와 임펄스 제어를 수행한 결과, 다음과 같은 결론을 얻었다. (1) 공기압 실린더의 정마찰과 동마찰을 추정할 수있는 마찰력 관측기를 설계하고, 그 유효성을 검토하였다. (2) 공기압 실린더 위치제어계에 H∞ 제어와 임펄스제어를 동시에 수행한 결과, 과도응답 특성은 큰차이가 없지만 정상상태 오차를 줄이는 데 임펄스제어가 효과적인 것을 확인하였다.	기계공학	null		kci_detailed_000118.xml
ART001748004	oai_dc	대유량 솔레노이드 밸브 개발에 관한 연구	A Study on Development of High Flow Solenoid Valves	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정찬세(울산대학교); 양순용(울산대학교)" ]	본 연구는 대유량 솔레노이드 밸브 개발을 위한 연구를 수행하였고 다음과 같은 결론을 구하였다. 1) 대유량 솔레노이드 밸브의 작동원리 및 기초이론을 정립하였다. 2) AMESim을 이용하여 대유량 밸브를 모델링하였으며 시뮬레이션 결과를 통하여 밸브의 각 파라미터에 따른 밸브의 거동을 확인 하였다. 3) 대유량 솔레노이드 밸브의 상부 및 하부 다이아프램 오리피스 직경에 따른 밸브의 거동을 검증하였다. 4) 기초 이론 및 시뮬레이션을 기반으로 대유량 솔레노이드 밸브를 설계하고 제작하였다. 5) 공압 솔레노이드 밸브의 성능 시험을 위한 시험장치를 설계 및 제작하였다. 6) 제작된 성능시험기를 통한 실험으로 개발된 제품의 특성 및 성능을 시험하였고 제품으로써의 가능성을 확인하였다.	기계공학	null		kci_detailed_000118.xml
ART001748038	oai_dc	Development of a Virtual Excavator using SimMechanics and SimHydraulic	Development of a Virtual Excavator using SimMechanics and SimHydraulic	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "레광환(울산대학교); 정영만(울산대학교); 웬치탄(울산대학교); 양순용(울산대학교)" ]	Excavation is an important work in mining, earth removal and general earthworks. Nowadays, automation in excavator has been studied by several researchers. In the excavator research methods, simulation is one of the low cost methods for applied to test safely. In this paper, designed a virtual hydraulic excavator that with the control and the dynamic. At first, the simulation of hydraulic system for excavator’s attachment such as boom, arm and bucket using Matlab/Simhydraulic is presented. Second, the dynamic model of excavator is distributed to combine with the hydraulic system. For controlling this system, electric joysticks are used to operate the orifice open areas in Main Control Valve. The simulation result is described to analysis the performance of this virtual excavator.	기계공학	null		kci_detailed_000118.xml
ART001798157	oai_dc	유압 베인 펌프에서의 탄성유체윤활 해석	Elastohydrodynamic Lubrication Analysis in Hydraulic Vane Pump	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "박태조(경상대학교)" ]	본 논문에서는 유한차분법과 뉴우튼-랍슨 방법을사용하여 유압 베인 펌프의 베인과 캠링 사이에서 발생하는 접촉길이가 유한한 선접촉 EHL 문제를 처음으로 수치해석하였다. 이때, 베인 폭방향으로의 유압유 누설은 제한하였다. 이 결과, 최대 유체압력과 최소유막두께는 항상 베인의 접촉폭 양단부에서 발생하였다. 또한, 동일한 운전조건에 대하여 로울러 베어링의 경우보다 발생압력은 낮고 유막두께는 크게 되므로 윤활상태는 상대적으로 양호할 것으로 예측되었다. 본 논문의 수치해석 방법과 결과는 베인 펌프의베인과 캠링의 설계 및 성능향상에 유용하게 사용될수 있을 것으로 기대된다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.3.007	kci_detailed_000118.xml
ART001798155	oai_dc	브레이크 압력 추정을 적용한 구동력 제어	Traction Control with Brake Pressure Estimation	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김세윤(강릉원주대학교)" ]	브레이크 압력의 추정을 통해 브레이크 압력을 제어할 수 있는 알고리즘을 구성하였고 차량 구동력 제어에 이를 접목시켜 차량 적용성을 고찰하여 얻은 결과는 다음과 같다. 1) 솔레노이드 밸브의 구동신호와 작동시간을 이용하여 브레이크 압력을 추정하는 방법을 제안하였고브레이크 압력 형성 실험을 통해 얻은 결과로부터추정 방법의 타당성을 확인하였다. 2) 차량 구동력 제어의 시뮬레이션 결과로부터 브레이크 압력을 제어 변수로 정하여 직접 제어할 수있는 가능성을 확인하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.9.3.001	kci_detailed_000118.xml
ART001798167	oai_dc	다이어프램형 밸브의 유량특성과 동적성능에 관한 연구	A Study on Flow Rate Characteristic and Dynamic Performance on Diaphragm Solenoid Valve	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정찬세(울산대학교); 양순용(울산대학교)" ]	본 연구는 다이어프램 밸브의 유량특성과 동적성능에 대하여 연구를 수행하였고 다음과 같은 결론을도출하였다. 1) 다이어프램 밸브의 작동원리 및 기초이론을 정립하였고 밸브의 성능에 영향을 미치는 파라미터를정리하였다. 2) AMESim을 이용하여 다이어프램 밸브를 모델링하였으며 시뮬레이션 결과를 통하여 밸브의 다이어프램 오리피스 면적에 따른 밸브의 거동을 확인 하였다. 3) 다이어프램 밸브의 오리피스 직경에 따른 밸브의 거동을 실험을 통하여 검증하였다. 4) 다이어프램 오리피스 면적이 작을수록 유효단면적이 넓은 것을 확인하였다. 5) 다이어프램 오리피스 면적에 따른 밸브의 동적성능은 큰 차이가 나지 않는 것을 확인하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.3.027	kci_detailed_000118.xml
ART001798163	oai_dc	유압실린더-토글 서보 메카니즘의 모델링 및 운동제어	Modeling and Motion Control for Hydraulic Cylinder-Toggle Servomechanism	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조승호(홍익대학교)" ]	본 연구에서는 토글 메카니즘을 MBS기법으로 3D CAD모델링 한 후, AC서보모터-정용량형 기어펌프를 사용하는 유압실린더와 인터페이스 시켜 버추얼디자인 모델을 구축하였다. 고성능의 서보응답과 고 에너지 효율의 결합은 오늘날 사출성형기에 있어서는 필수불가결하다. 사출성형 공정에서 클램프 실린더는 다양한 작동 조건하에서 작업이 수행되도록 요구된다. 따라서 강인한 추적 제어 성능이 요구되므로 PID제어와 슬라이딩 모드를결합하는 방식을 도입하였다. 토글 메카니즘의 크로스헤드와 가동형판의 속도, 변위응답 특성을 고찰하기 위하여, 개회로 시뮬레이션을 수행하였다. 이로부터 전달함수의 설계 파라미터 값을 추출하여 제어기설계에 이용하였다. 슬라이딩모드를 결합에 의하여 응답속도를 빠르게하는 효과가 현저하여, 그 결과 가동형판의 응답성이향상되고 아울러 형체력이 빠르게 형성되므로 DCT 의 단축도 가능하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.3.021	kci_detailed_000119.xml
ART001798161	oai_dc	피드백 선형화 보상기와 외란 관측기를 이용한 2개 유압 실린더의 동기 제어	Synchronization Control of Two Hydraulic Cylinders Using Feedback Linearization Compensator and Disturbance Observer	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "감주성(부경대학교); 오동훈(부경대학교); 이일영(부경대학교); 김지웅(SG 서보 (주)); 이현철(SG 서보 (주))" ]	본 논문에서는 2개의 유압 실린더 위치를 동기제어하기 위한 제어 알고리즘을 제안하였다. 제안한 알고리즘은 각각의 실린더 위치를 제어하기 위한 부분과동기제어를 위한 부분으로 구성된다. 각각의 실린더위치를 제어하기 위한 알고리즘으로는 피드백 선형화보상기와 외란 보상기가 적용되었으며, 동기화 제어보상기로는 교차형 오차 판별기와 PI제어기가 사용되었다. 제안한 제어 알고리즘을 적용한 2축 유압 실린더동기제어 시스템의 제어 성능을 시뮬레이션을 통하여 조사하였으며, 서로 다른 크기의 외란이 작용하는 2 개 실린더의 위치를 신속하고 정밀하게 제어할 수 있음을 확인하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.3.014	kci_detailed_000119.xml
ART001772782	oai_dc	스마트폰 앱을 이용한 산업용 엔진의 모니터링 시스템 개발에 관한 연구	A Study on Development of Industrial Engine Monitoring System Using Smart Phone Application	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정찬세(울산대학교); 김용석(울산대학교); 정영만(울산대학교); 고주현(울산대학교); 정광식(명품기업); 이효성(명품기업); 양순용(울산대학교)" ]	본 연구에서는 산업용 중형엔진의 시운전환경개선을 위하여 ISM Band의 통신을 통해 엔진의 시운전데이터를 모니터링 하는 유·무선 통신시스템을 설계하고 제작하다. 또한 스마트폰 어플리케이션을 이용한 모니터링 시스템을 개발하고 테스벤치를 구축하였으며, 다음과 같은 결과를 도출하였다. 1) 데이터 획득시스템(DAQS)인 RTU(Remote Terminal Unit)와 게이트웨이인 MCU (Master Control Unit)를 개발하였다. 2) Zigbee 통신을 이용한 무선 통신 모니터링 시스템을 구축하였다. 3) PC 기반의 GUI 프로그램을 개발하고 유무선 통신 테스트벤치를 구축하였다. 4) WiFi 통신과 스마트폰 어플리케이션을 이용한실시간 모니터링시스템을 개발하였다. 5) 기 개발된 시스템의 테스트벤치를 통한 검정시험을 수행하여 산업용 엔진 운전데이터의 모니터링시스템으로 적용 가능성을 확인하였다	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.2.007	kci_detailed_000119.xml
ART001772773	oai_dc	에어스프링 시스템의 성능 개선에 관한 연구	A Study on the Performance Improvement of an Air Spring System	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "장지성(부경대학교)" ]	This study describes a method which can attenuate reaction force effectively for an air spring system composed of an air spring and auxiliary chamber. For the analysis, the nonlinear governing equation of the air spring system is derived. For a performance improvement of the system, change of the heat transfer effect and the mass flow rates is included in the analysis of the air spring system. The simulation study is presented to show the reaction force is changed by variations in heat transfer characteristics and the air spring system of isothermal process has the best performance. As a result, to improve attenuation characteristics of reaction force, a process in the air spring system should be maintained near isothermal process.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.2.001	kci_detailed_000119.xml
ART001772803	oai_dc	강제배기를 이용한 굴삭기 공기조화 시스템에 관한 연구	A Study on Air-Conditioning System for Excavator using Forced Exhaust	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "황지현(울산대학교); 정찬세(울산대학교); 고주현(울산대학교); 양순용(울산대학교)" ]	본 연구에서는 강제배기를 이용한 굴삭기 캐빈의공기조화 시스템에 대한 연구를 수행하여 다음과 같은 결론을 도출하였다. 1) 강제배기를 이용한 굴삭기 캐빈 공기조화 시스템의 원리와 기초이론을 정립하였다. 2) AMESim을 이용하여 강제배기를 이용한 공기조화 시스템의 모델을 개발하였으며 흡입공기온도와배기유량에 따른 캐빈 내부 온도변화를 확인하였다. 3) AMESim 시뮬레이션을 통하여 흡입공기온도가낮고 배기유량이 많을수록 캐빈 내부 온도가 급격히낮아지는 것을 확인하였다. 4) 실내실험을 통하여 자연대류를 이용한 캐빈 온도변화와 강제대류를 이용한 캐빈 온도변화를 비교하였으며 52℃에서 30℃까지 낮아지는 시간은 강제대류가 약 250s 빨리 낮아지는 것을 확인하였다. 5) 실외실험을 통하여 실제 일사량이 적용된 동안캐빈의 내부온도를 측정하였으며 배기유량을 변경하고 태양열을 받는 면적을 변경하여 강제배기 시스템의 적용 가능성을 검증하였다. 본 연구에서는 강제배기 시스템의 적용 가능성을검증하기 위하여 개방형 캐빈을 자체적으로 밀폐형으로 변경하여 시스템을 구성, 실험하였다. 따라서 실제밀폐형 캐빈 보다 열악한 환경에서 시험을 수행하여실제 사용 환경에서의 성능은 실험에서 얻어진 결과보다 향상되리라 예상 된다 . 향후 각 굴삭기 캐빈의형태나 부피에 따른 시스템의 최적화를 위한 연구가진행되어야 할 것으로 판단된다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.2.023	kci_detailed_000119.xml
ART001772805	oai_dc	트랙터 8단 자동변속기 기어 열 설계	Gear Train Design of 8-Speed Automatic Transmission for Tractor	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "정규홍(대진대학교)" ]	트랙터는 다양한 부속작업기를 이용하여 농업, 축산업뿐만 아니라 소형 건설기계로도 활용되고 있으며빈번한 변속조작이 수반되는 작업의 효율성을 높이고운전자의 편의성 향상을 위하여 자동변속기능이 요구되고 있다. 본 연구에서는 국산화 개발이 시도되고 있는 100마력급 트랙터 자동변속기에 적용되는 8단 주 변속 기어열을 3축과 2축을 갖는 2가지 방식으로 설계하였으며속도분석을 통해 동력전달체계와 변속특성을 고찰하였다. 또한 동력전달경로에 대한 기구학적 분석을 통해 각 변속단에서의 변속비가 주어졌을 때 이를 구현할 수 있는 기어비를 계산하는 방법을 제시하였다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.2.030	kci_detailed_000119.xml
ART001772791	oai_dc	에너지보존과 토크평형을 이용한 제로터 유압 펌프/모터의 배제용적 해석 - 내․외부로터 회전 경우 -	An Analysis on Volumetric Displacement of Hydraulic Gerotor Pump/Motor using Energy and Torque Equilibrium - First Report: Case of Rotation of Inner and outer Rotors -	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김성동(금오공과대학교); 김대명((주)대화산기); 함영복(한국기계연구원)" ]	본 연구의 주요 결론은 다음과 같이 요약된다. 1) 제로터 기구에서 내․외부로터의 중심과 피치점이 일정하게 주어진 상태에서 내․외부로터 의 로우브 수에 반비례하는 속도로 회전하는 운동형태의경우에 대하여 모터에 공급되는 유압에너지와 모터측의 기계적 에너지 사이의 에너지 보존원리와 로터에대한 토크평형을 이용하여 모터용적을 산출하는 방법을 제시하였다. 2) 유압에너지와 모터측의 기계적 에너지 사이의에너지 보존원리와 로터에 대한 토크평형을 이용하여모터용적을 산출하는 결과공식이 회전날개길이법의 배제용적 결과 수식이 동일함을 이론적으로 증명하였다. 3) 또 다른 검증방법으로서 접촉점 사이의 챔버용적을 이용하여 산출된 배제용적 결과와 수치해석적인 방법으로 비교하였으며, 에너지 보존원리와 로터에 대한 토크평형을 이용한 모터용적과 유량에 관한이론과 수식의 타당성을 확인하였다. 4) 에너지보존과 토크평형을 이용하여 유량과 배제용적을 산출하는 방법의 계산과정이 단순히 내외부로터의 접촉점의 좌표만을 이용하기 때문에 복잡한형상의 내․외부로터사이 챔버용적을 구하는 방법보다 간단하다. 5) 에너지보존과 토크평형 이용법이 회전날개길이법과 계산과정의 난이도가 유사하지만, 축의 구동 토크와 배제용적의 상관관계를 직접적으로 보여주기 때문에 토크사양이 주어진 유압모터의 설계에 이용이효율적일 것이다.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2013.10.2.013	kci_detailed_000119.xml
ART001690642	oai_dc	항공기의 도어 댐퍼용 교축 오리피스의 설계	Design of Throttle Orifices for an Aircraft Door Damper	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "권용철(한국항공대학교); 김종혁(한국항공대학교); 홍예선(한국항공대학교); 김상범(한화)" ]	In this study the flow rate-to-pressure difference characteristics of short-tube type damping orifices for an aircraft door damper were investigated by CFD analyses and experiments. As the design parameters of the damping orifice its diameter, inlet and outlet angle, tube length and the viscosity of the working fluid were taken into consideration. The results showed that the discharge coefficient of the orifices are dependant on the inlet and outlet angle and the oil viscosity, while their length plays an little significant role. Although the short-tube type damping orifice was employed to induce a turbulent flow, their discharge coefficient decreases rapidly as the oil viscosity gets higher than 50mm2/s. Therefore, in order to determine the orifice size,satisfying the working temperature range of the door damper, the oil viscosity as well as the friction force on the damper piston should be kept within proper values. For the verification of the CFD analysis results the actual performance of a door damper was measured and compared with them.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2012.9.3.023	kci_detailed_000119.xml
ART001690579	oai_dc	사출성형 실린더의 적응제어 방식 속도 및 압력제	Adaptive Control Based Velocity and Pressure Control for Injection Molding Cylinder	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "조승호(홍익대학교)" ]	This paper deals with the issue of model reference adaptive control strategy to control the injection molding machine. Prior to controller design, a pair of transfer functions are derived for the injection and dwelling process based on mathematical models of components. As external disturbances to examine the robustness of the proposed controller, nozzle clogging and contraction of molded objects are considered and realized by proportional valve. The overall simulation system, consisting of hydraulic components, controller and sensors, is implemented using the components of commercial software SimulationX. The simulation results confirm the proposed scheme's efficiency and robustness.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2012.9.3.001	kci_detailed_000119.xml
ART001690583	oai_dc	피드백 선형화 제어기를 사용한 1/4 차량 현가장치 시뮬레이터의 위치 제어	Position Control of a 1/4 Car Suspension Simulator using a Feedback Linearization Controller	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "김태형(대한항공); 이일영(부경대학교)" ]	In the study, a control strategy using a feedback linearization compensator and a disturbance observer was suggested and applied to a hydraulic control system for a vehicle suspension simulator. Although the hydraulic system has comparatively big external loads composed by constant and varying loads, it is ascertained that excellent control performances are obtained with the suggested control strategy.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2012.9.3.008	kci_detailed_000119.xml
ART001690646	oai_dc	콤플렉스법에 의한 롤러-링크 부착형 전도수문 구동용 유압실린더의 최적 설치점 설계	Design of Optimal Locating Point of the Hydraulic Cylinder Actuating a Roller-Link Type Rotating Floodgate	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "이성래(건양대학교)" ]	The hydraulic cylinder is used for actuating the roller-link type rotating floodgate which controls the volume of water in the reservoir. The locating points of hydraulic cylinder are restricted to the limited space and determined to minimize the cylinder force necessary for actuating the floodgate. Generally, the head end point of cylinder is fixed at underground and the rod end point of cylinder is connected to the support link. Therefore there exist three design variables to be determined to minimize the cylinder force within the rotating range of floodgate. First, the mathematical model of the roller-link type rotating floodgate is derived to find the cylinder force corresponding to the floodgate angle. Then, the optimal locating point of hydraulic cylinder is searched using the complex method that is one kind of constrained direct search method.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2012.9.3.029	kci_detailed_000119.xml
ART001690620	oai_dc	Position control of Electro hydrostatic actuator (EHA) using a modified back stepping controller	Position control of Electro hydrostatic actuator (EHA) using a modified back stepping controller	{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }	[ "도안녹치남(울산대학교); 윤종일(울산대학교); 안경관(울산대학교)" ]	Nowadays, electro hydrostatic actuator (EHA) has shown great advantages over the conventional hydraulic actuators with valve control system. This paper presents a position control for an EHA using a modified back stepping controller. The controller is designed by combining a backstepping technique and adaptation laws via special Lyapunov functions. The control signal consists of an adaptive control signal to compensate for the nonlinearities and a simple robust structure to deal with a bounded disturbance. Experiments are carried out to investigate the effectiveness of the proposed controller.	기계공학	null	http://dx.doi.org/10.7839/ksfc.2012.9.3.016	kci_detailed_000119.xml

ART001959932

oai_dc

압전 밸브용 압력 레귤레이터

Pressure Regulator for Piezoelectric Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "윤소남(한국기계연구원); 김찬용(한국기계연구원); 서우석(한국기계연구원); 박중호(한국기계연구원); 함영복(한국기계연구원)" ]

The pressure regulator which is used for controlling the reducing pressure in the piezoelectrically driven pneumatic valve has been studied. The pneumatic valve of this study object is 2-stage type and consists of a piezoelectric actuator, a controller, a poppet valve and a pressure regulator. Nominal flow of 50 1pm, maximum operating pressure of 0.9MPa and frequency characteristic of 10Hz and over are required in this pneumatic valve, but the pressure regulator is needed because piezoelectric actuator has no ability to control the pressure of 0.9MPa directly. In this study, bimorph type PZT actuator of 25.2 mm(L)x7.2 mm(W)x0.5 mm(H) with constant of -220x10-12 CN-1 was proposed and investigated. Maximum operating force of 0.052 N and maximum displacement of 63 ㎛ were gotten from the fabricated PZT actuator. From the analysis results, the orifice diameter or 0.6mm for a piezoelectric actuator was derived and then the pressure regulator which can be operated under 0.15 MPa easily was designed and manufactured. Performance and effects of design parameters were simulated by the Simulink of Matlab software, and it was confirmed that the performance characteristics of manufactured pressure regulator are superior in the common use pressure of 0.5 MPa to 0.7MPa, The results show that the proposed pressure regulator is suitable for the pneumatic valve with a PZT actuator.

기계공학

null

kci_detailed_000118.xml

ART001959934

oai_dc

굴삭기 리턴 라인 유동소음 감소에 관한 연구

Research of Noise Reduction about Excavator Return Line

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "강병일(두산인프라코어(주)); 장달식(두산인프라코어); 김성재(두산인프라코어(주)); 권영식(두산인프라코어(주))" ]

In this paper the noise source and the amplifying mechanism are analyzed to reduce the noise of the excavator return line using the experimental approach and the CFD simulation. The result says that the reason of noise generation and pipe vibration caused by the cavitation at the main control valve and the level of noise is proportional to the valve back pressure at the return line. The methodology to reduce this noise was proposed and verified by the vehicle test.

기계공학

null

kci_detailed_000118.xml

ART001959937

oai_dc

유압 호스에서의 주파수 계열 음속 계측법 개발

A Method for Measuring the Frequency Series Wave Speed in Hydraulic Hose

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "강만곤(부경대학교); 이일영(부경대학교)" ]

With the increasing concerns on noise and vibration in hydraulic fluid power systems, it is Important to find better way to reduce noise and vibration. In this study, the authors survey former researches on hose(viscoelastic tube) modeling in advance. And a summary of several existing methods for measuring the speed of sound in the fluid in pipes is presented. Their basic principles, advantages and limitations are compared. And The authors suggest a for simple identification procedure to obtain wave speed in hose by just using an experimental pressure data for the object tube with hose. In the new procedure, flow in hose is basically modeled by transfer matrix method, and ware speed in hose is obtained as data in frequency series. The wave speed in hose as data in frequency series will be used to compute the pressure pulsation attenuation in hydraulic pipe systems. The computed results are compared with the experimental ones, and the validity of the new procedure to obtain wave speed in hose is confirmed.

기계공학

null

kci_detailed_000118.xml

ART001959935

oai_dc

전기∙유압 서보 시스템의 제어성능 비교

Comparison of Control Performance in Electro∙hydraulic Servo Systems

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김도태(경일대학교); 박경섭(경일대학교)" ]

A controller design procedure for an electro-hydraulic positioning systems has been developed using H∞ control. The generalized plant models and weighting function for multiplicative uncertainty modelling error was presented along with H∞ controller designs in order to investigate the robust stability and performance. Both disturbance rejection and command tracking performances were improved with H∞ controller, and the better uniformity of time response is achieved across wide range of operating conditions than the PID,LQR and LQG control scheme. The multiplicative uncertainty case was specifically suited for the design of an electro-hydraulic positioning control systems using H∞ control.

기계공학

null

kci_detailed_000118.xml

ART001959926

oai_dc

유압서보밸브의 인-프로세스 성능 진단에 관한 연구 1 - 유압실린더 위치제처계의 경우 -

A study on In-Process Performance Diagnosis of Hydraulic Servovalves - First Report : position Control System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 김경호((주) TFS Global); 송재수(주) TFS Global); 함영복(한국기계연구원); 이재천(계명대학교)" ]

In this paper, an in-process diagnosis method for performance of position control servo system was studied, which was based upon null bias, slew-ratio and delay time measurement. Slew-rate ratio and delay time were analyzed by theoretical analysis, computer simulation and experiment. As a result of these analysis, when spool of servovalve was weared, slew-rate ratio was decreased and delay time was increased.

기계공학

null

kci_detailed_000118.xml

ART001959929

oai_dc

공압실린더의 누설유량 계측방법에 관한 연구

A Study on the Measurement Method of Leakage Flow-rate for Pneumatic Cylinder

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "장지성(부경대학교); 지상원(부경대학교 제어기계공학과); 정지현(부경대학교); 강보식(한국기계연구원)" ]

In this study, a measurement method of leakage flow-rate for pneumatic driving apparatus is proposed. The existing measurement methods of leakage flow-rate of air need disassemble the test component. Therefore, there is no effective method to measure the leakage flow-rate while operating pneumatic driving apparatus. In this study, the leakage flow-rate is measure form the pressure change in an isothermal chamber that can realize isothermal conditions by stuffing steel wool into it. Therefore, wide range of flow-could be measured only from the pressure response and the leakage flow-rate can be measured during operating pneumatic driving apparatus. The effectiveness of the proposed method is proved by experimental results.

기계공학

null

kci_detailed_000118.xml

ART001959924

oai_dc

MR 밸브 내장형 서보 액추에이터의 힘 제어에 관한 연구

A study on the force control of a servo actuator with built-in MR Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "안경관(울산대학교); 송주영(울산대학교 대학원); 김정수(울산대학교); 안영공((재)송도테크노파크); 박중호(한국기계연구원)" ]

A servo actuator with a valve using MR (Magneto-Rheological) fluid is proposed for fluid control systems. The MR fluid is well known as a functional fluid whose apparent viscosity is controlled by the applied magnetic field strength. The pressure in the MR cylinder can be controlled by the applied magnetic field strength. Good points of the MR cylinder are more simple, compact and reliable structure than a conventional oil hydraulic cylinder. The experimental results show that the MR cylinder could used as a servo actuator.

기계공학

null

kci_detailed_000118.xml

ART001959907

oai_dc

공압시스템의 설계 파라미터 최적화

Optimization of Design Parameters of a Pneumatic System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "엄태준(순천향대학교)" ]

This paper presents optimization of a pneumatic control system whose design parameters have been optimized so that the desired dynamic characteristics of cylinder position was obtained. The pneumatic system is used as transferring and stacking equipment for solid freeform fabrication system which has been widely used in design verification applications. The pneumatic system mainly consists of pneumatic control valves and cylinders. The system was modeled by using several principles for pneumatic components. The system was optimized to obtain dynamic performance with enough damping to reduce cylinder vibration. A fuzzy controller has been applied to fulfill the dynamic performance requirements of the pneumatic system. The simulation results show that the fuzzy controller is more effective than a PD controller.

기계공학

null

kci_detailed_000118.xml

ART001959917

oai_dc

유압펌프 및 모터 피스톤 조립체의 수명예측을 위한 가속실험 모델

Accelerated Life Test Model for Life Prediction of Piston

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이용범(한국기계연구원(신뢰성평가센터)); 김형의(한국기계연구원); 유영철(한국기계연구원); 박종호(충남대학교)" ]

The safety factor of hydraulic piston & motors due to high pressurization, high speedization and low weight/volume realization to enhance the output density shows a tendency to decrease. Therefore more effective test methods are necessary to predict the exact life. The failure of hydraulic pumps & motors operating in high pressure and high speed mainly occurs in piston-shoe assemblies, and the major failure mode is wearout of the shoe surface. The sensitive parameters in the endurance life test are speed, pressure and temperature, and the failure production increases in proportion to the operating time. In this research, the authors propose the combined accelerated life test model using the analysis method of the combined accelerated life test results of piston-shoe assemblies by applying simultaneously high speed, high pressure and high temperature in accordance with variation of speed, pressure and temperature to reduce the life test time.

기계공학

null

kci_detailed_000118.xml

ART001959910

oai_dc

VSC 유압유닛의 압력 추정기 및 제어기 설계에 관한 연구

A Study on Estimator and Controller Design of VSC Hydraulic Unit

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이교일(서울대학교); 김범주(서울대학교); 유승진(서울대학교)" ]

This paper presents modeling and estimator/controller design for the hydraulic system in Vehicle Stability Control(VSC) system. A nonlinear mathematical model of the VSC hydraulic system is proposed and its accuracy is experimentally verified. A brake pressure estimator is then designed based on the derived mathematical model of VSC hydraulic system. And a disturbance observer, which compensates the estimation error between the brake pressure and the computed brake pressure is also designed to enhance the accuracy of the estimator. The proposed controller has the from of a feedback controller and determines explicitly the on/off ratio of valves' driving PWM signals by means of making use of the simplified mathematical model in the VSC hydraulic system. The performance of the designed controller whose signal is generated by the brake pressure estimator is validated through experimental results.

기계공학

null

kci_detailed_000118.xml

ART001959918

oai_dc

기어펌프∙모터 이끝 틈새의 영향에 관한 연구

A Study on the Effect of Gear Teeth End-Gaps for Hydraulic Gear Pumps and Motors

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정헌술(군산대학교); 풍려려(군산대학교); 오석형(군산대학교)" ]

In order to improve the efficiency of hydraulic gear pumps or motors especially for high operating pressure, power losses due to viscous friction and leak flow through gear teeth end-gaps are considered in this paper. Optimal gaps minimizing the power loss for pumps and motors with uniform heights of gaps are analysed first. And the effect of the shapes of gaps with unequal heights on the power loss are studied and discussed by simulation. Considering that the outer shell facing gear teeth may expand due high internal pressure or thermal stress, the results drawn in this paper can be used for the design of high efficiency pumps and motors.

기계공학

null

kci_detailed_000118.xml

ART001959905

oai_dc

액시얼 피스톤 펌프의 맥동유량 시뮬레이션 모델

Flow Ripple Simulation Model of Axial Piston Pump

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이일영(부경대학교); 박정환(부경대학교); 강만곤(부경대학교)" ]

This paper presents a theoretical study of the delivery flow ripple produced by a swash plate type hydraulic piston pump for the purpose of developing a computer simulation program capable of predicting the pump source flow ripple accurately at the design stage. Particular attention has been paid to the development of the theoretical model by clarifying quantitatively the design influences of key parts of valve plate such as relief groove and pre-compression/expansion.

기계공학

null

kci_detailed_000118.xml

ART001959898

oai_dc

비례솔레노이드 형상 최적설계에 관한 연구

A Study on Shape Optimization of Electro-Magnetic Proportional Solenoid

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "윤소남(한국기계연구원); 함영복(한국기계연구원); 강정호(삼성종합기술원)" ]

There are two types of solenoid actuator for force and position control of the fluid power system. One is an on-off solenoid actuator and the other is an electro-magnetic proportional actuator. They have some different characteristics for attraction force according to solenoid shape. Attraction force of the on-off solenoid actuator only depends on flux density. And the stroke-force characteristics of the proportional solenoid actuator are determined by the shape of the control cone. In this paper, steady state characteristics of the solenoid actuator for electro-hydraulic proportional valve determined by the shape of control cone are analyzed using finite element method and it is confirmed that the proportional solenoid actuator has a constant attractive force in the control region independently on the stroke position. And the shape of control cone optimized using 1+1 evolution strategy to get a constant force, In the optimization algorithm, control cone length, thickness and taper length are used as a design parameter.

기계공학

null

kci_detailed_000118.xml

ART001959903

oai_dc

압전액추에이디터를 이용한 비례 가스유량제어밸브

Proportional Gas Flow Control Valve Using Piezo Actuator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "윤소남(한국기계연구원); 김찬용(경북대학교); 함영복(한국기계연구원); 이경우(경원 훼라이트공업㈜); 강정호(삼성종합기술원)" ]

A household gas valve is used for flow control of LPG(Liquefied Petroleum Gas) or LNG(Liquefied Natural Gas) of which pressure is about 20㎜(≑0.0196 [bar]). Currently, two kinds of valves such as rotary type and button type are widely used in many applications. But, these valves have some problems that they are not controllable and reliable. Piezo actuation combined with modem microelectronics provides a reliable, quiet, low energy, infinitely adjustable gas valve. In this paper, gas valve using piezo actuator which are bimorph and a circle type was studied. Also, Prototype for gas valve was manufactured and characteristics of the prototype gas valve were analyzed.

기계공학

null

kci_detailed_000118.xml

ART001968153

oai_dc

토크모터의 정특성과 동특성 해석

An Analysis of Static and Dynamic Characteristics of Torque Motor

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "허준영(한국기술교육대학교); 박창순(한국기술교육대학교)" ]

In the early of 1950, the high response magnetic torque motor was developed for driving electro-hydraulic servo valves. Since then it has been broadly used for industrial application and the research of development or improvement of the torque motor is still being conducted. The purpose of this study is to present useful design criteria for the torque motor design. For this, torque motor is modelled and linearized. The static characteristics of the torque motor are investigated by direct computation of the derived linearlized equations. The dynamic characteristics of the torque motor are investigated with the derived transfer function by using Matlab and compared with the results of the linearlized analysis by using AMESim simulation with actual values of the physical parameters. Finally, the design criteria obtained from the analysis are reviewed.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2015.12.1.009

kci_detailed_000118.xml

ART001968176

oai_dc

선박 유압 조타장치 부하의 추정

Estimation of Load on Ship's Hydraulic Steering Gear

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "지상원(부경대학교 기계시스템공학과); 이일영(부경대학교); 정은석(한국해양대학교); 김병곤(유원산업); 오재민(부경대학교)" ]

For testing a newly designed ship's steering gear, a steering gear test bench with a steering gear to be tested and a load generation part should be prepared. The load given to the steering gear has to be pertinent to the load generated in a targeted ship. In this study, the authors suggest a process of estimating the load given to steering gears in ships. At first, a test for measuring the load in the steering gear of a real ship was conducted. Then, a process was developed to compute rudder driving torque and force by using basic equations including some empirical equations on ship's steering. The test results and the computation results on the load in the steering gear were compared, As a result, the process suggested in this study for estimating load in ship's steering gears was verified.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2015.12.1.015

kci_detailed_000118.xml

ART001968179

oai_dc

로드리스 실린더의 수명 특성에 관한 연구

A Study on the Life Characteristic of Rodless Cylinder

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이충성(한국기계연구원); 강보식(한국기계연구원); 임재학(한밭대학교)" ]

Pneumatic cylinders are classified into rod-type pneumatic cylinders and rodless pneumatic cylinders depending on the presence of the rod. Rodless cylinders have a constant area and have no deflection. Rodless cylinders are widely used in automatic systems requiring high-speed performance and high-precision transportation. However, the research of the pneumatic cylinder has been focused on the structure and life characteristics. In this research, aging characteristics and shape parameter analysis which are related to the lifetime were investigated. By conducting the lifetime tests with two different materials for the transfer plate, the failure mode and lifetime characteristics were analyzed. By the Anderson-Darling (A-D) verification based on the complete data set, the analysis results of lifetime distribution, shape parameter, and scale parameter were provided.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2015.12.1.021

kci_detailed_000118.xml

ART001968151

oai_dc

A Study on Thermal Analytical Model for a Dry Dual Clutch

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "Liu, Hao(계명대학교); 이재천(계명대학교); 노유정(계명대학교); 조종환(평화발레오); 이희락(평화발레오); 고재욱(평화발레오); 강지우((주)평화발레오)" ]

The stability of friction characteristics and thermal management for a dry type dual clutch transmission (DCT) are inferior to those of a wet clutch. Too high temperature resulting from frequent engagement of DCT speeds up degradation or serious wear of the pressure plate or burning of the clutch disk lining. Even though it is significantly important to estimate the temperature of a dry double clutch (DDC) in real-time, few meaningful study of the thermal model of DDC has been known yet. This study presented a thermal analytical model of lumped parameters for a DDC by analyzing its each component firstly. Then a series of experimental test was carried out on the test bench with a patented temperature telemetry system to validate the proposed thermal model. The thermal model, whose optimal parameter values were found by optimization algorithm, was also simulated on the experimental test conditions. The simulation results of DDC temperature show consistency with the experiment, which validates the proposed thermal model of DDC.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2015.12.1.001

kci_detailed_000118.xml

ART001857195

oai_dc

CFD를 이용한 유압 서보밸브의 열유체 해석

THD Analysis of a Hydraulic Servo Valve Using CFD

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정요한(경상대학교 대학원 기계항공공학부); 박태조(경상대학교)" ]

Hydraulic servo valves are widely used in various fluid power systems because of their fast response and precision control. In this paper, we studied the effect of metering notch shapes and amount of their openings on the flow characteristics within the spool valve using a computational fluid dynamic (CFD) code, FLUENT. To obtain the results for more realistic operating conditions, viscous heating due to the jet flow and viscosity variation of the hydraulic fluid with temperature were considered. For two types of notch shape, streamlines, oil temperature and viscosity distributions, and variations of flow and friction forces acting on spool were showed. The flow and friction forces affected by the metering notch shapes and their openings, and oil temperature rise near metering notch was significant enough to results in the jamming phenomenon. A thermohydrodynamic (THD) flow analysis adopted in this paper can be used in optimum design of hydraulic servo valves.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.1.008

kci_detailed_000118.xml

ART001857183

oai_dc

Application of Secondary Control Hydrostatic Transmission in A Multi-Point Absorbing Wave Energy Converter

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "도황팅(울산대학교); 안경관(울산대학교)" ]

This paper presents a novel concept of wave energy converter for electric generation from the ocean wave energy. In this paper, a Multi-Point Absorbing Wave Energy Converter, shortened as MPAWEC by using Secondary Control Hydrostatic Transmission (SCHST) was proposed. The power take-off (PTO) system in the proposed MPAWEC includes multi heaving buoys to drive hydraulic pumps placed at different points. The application of SCHST in MPAWEC gives some advantages, such as longevity of hydraulic components; more energy is harvested; the variation of the pressure in the accumulator limited; therefore the accumulator volume is reduced and the output speed is more stable, etc. A PID controller was designed for speed control of the hydraulic motor. The simulation results indicated that the speed of the generator was ensured with the relative error as 0.67%; the efficiency of the proposed system was 71.4%.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.1.001

kci_detailed_000118.xml

ART001857215

oai_dc

Analysis of the Mathematical Model of a Variable Displacement Vane Pump for Engine Lubrication

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "딩광청(울산대학교); 안경관(울산대학교); 이재신(울산대학교)" ]

Variable displacement vane-type oil pumps represent one of the most innovative pump types for industrial applications, especially for engine lubrication systems. This paper presents a complete and accurate mathematical model for a typical variable displacement vane-type oil pump. Firstly, its theoretical model is revised. Secondly, an analysis of power loss factors of this pump type is carefully investigated to optimize the modeling accuracy. Finally, the estimated pump performance using the complete pump model is verified by numerical simulations in comparison with the practical tests.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.1.014

kci_detailed_000118.xml

ART001959422

oai_dc

에어밸런서 공압 회로의 설계 및 성능 실험

Pneumatic circuit design and Performance test of Air balancer

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원)" ]

Air balancer is a conveyance cargo-handling machine, used in assembly and process lines of car and machining industries. This can lift up an object, the weight of which is from 5 to 200 kg, and moves it to a position. As industrial technologies evolve, it is required to move an object and fit it into a specified position with greater accuracy, rather than performing simple tasks such as lifting objects up and down as conventional ones do. There is also a demand to handle an object with one hand, rather than with two hands. Through designs of manifold unit for an air balancer funcion, pilot regulator unit to keep pressure constant, hand unit for an accurate load perception function, and air balancer circuit, this study enables everybody to work it with ease and convenience. Experiments and comparisons were conducted for the performance evaluation of the circuit.

기계공학

null

kci_detailed_000118.xml

ART001959419

oai_dc

굴삭기 시뮬레이터의 설계

Design of Simulator for the Excavator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원); 김정수(한국기계연구원)" ]

Recently, the cylinder of excavator is applied in the various environment. So, we need the development of the simulator for the excavator. The excavator has the effects of the decrease of the cost and improvement of the cylinder's performance. In this paper, we design the simulator for the excavator and makes an analysis of the dynamics and structure. The simulator was applied to the excavator's models of 10ton, 20ton and 30ton because we built the data base of a real excavator's cylinder of information in the experiment. And we used the FEM analysis for the comparative study on the characteristics.

기계공학

null

kci_detailed_000118.xml

ART001959413

oai_dc

유압시스템 구성품의 수명시험을 위한 무고장 시험시간의 산출

Determination fo No-Failure Test Times for the Life Test of Hydraulic System Components

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성래(건양대학교); 김형의(한국기계연구원)" ]

It is very important for the manufacturers to predict the life of hydraulic system components according to the results fo life tests. Since it takes too much time to test the hydraulic system components until fuilure, the no-fuilure test method is applied for the life test of them. If the shape parameter of Weibull distribution, the number of samples, the confidence level, and the assurance life are given, the no-fuilure test times of hydraulic system components can be calculated by given equations. Here, the procedures to obtain the no-fuilure test times of the hydraulic system components such as hydraulic motors and pumps, hydraulic cylinders, hydraulic valves, hydraulic accumulators, hydraulic hoses, and hydraulic filters are described briefly.

기계공학

null

kci_detailed_000118.xml

ART001959405

oai_dc

시일이 없는 유압 실린더용 피스톤의 이론해석

Theoretical Analysis of Sealless Piston for Hydraulic Cylinders

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "박태조(경상대학교)" ]

In this paper, a theoretical analysis is carried out to study the lubrication characteristics of sealless piston for hydraulic cylinders. The analytical pressure distributions are obtained solving one-dimensional Reynolds equation with partially tapered moving piston. Nearly analytical expressions for lateral forces acting on the piston and leakage flow rate through the clearance are also presented. Using the analytical expressions, the influence of design parameters on lubrication characteristics can be easily evaluated without numerical analysis. Composite-shaped piston which minimizes the leakage flow rate is the optimum in sealless piston for hydraulic cylinder.

기계공학

null

kci_detailed_000118.xml

ART001932915

oai_dc

직접제어 방식을 이용한 소형 지게차 변속감도 시뮬레이션에 관한 연구

A Study on Simulation of Shift Sensitivity of Small Forklift Transmission using Direct Control Method

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정영만(울산대학교); 양순용(울산대학교)" ]

The transmission control method of a small forklift is classified into a pilot control method and a direct control method. In the pilot control method, the complex hydraulic circuit consists of many components, making the production process too costly and time consuming. The direct control method contains fewer components that can be configured to simple hydraulic circuits. As another advantage, the input profile easily changes the shift sensitivity of the transmission. Therefore, this research considers the characteristics of the direct control method in the development of hydraulic system design. This paper will present a simulation of the direct control transmission using AMESim. First, modeling of the direct control method is obtained and simulated with real parameters. The simulation results then are carried out and compared with the experimental results to verify and analyze the characteristics of the direct control method.

기계공학

null

kci_detailed_000118.xml

ART001932935

oai_dc

EHA 밸브 성능시험 장치 개발

Development of Performance Test Equipment for Easy-Hill Assist Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교)" ]

When a manual transmission equipped car stops on an incline where the nose of the car is higher than the rear, hill-start control or hill-holder could prevent the vehicle from rolling backward as the car moves forward. The easy-hill assist valve consists of a check valve and a needle type ON/OFF solenoid valve connected in parallel; it is a hydraulic actuator that can maintain brake pressure using an electrical signal from the ECU. As the EHA valve is a safety-related component of the brake system, high reliability as well as superior dynamic performance is required for it to be applied in commercial vehicles. This paper presents the design of the EHA valve as a piece of equipment that can simulate the brake actuation pressure with a pressurizing piston. Following specific test standards, the experimental results validate the implemented functions of the test equipment, proving the test stand to be effective for the performance and endurance of the EHA valve.

기계공학

null

kci_detailed_000118.xml

ART001932917

oai_dc

에너지보존과 토크평형을 이용한 제로터 유압모터의 배제용적 해석-내부로터 공·자전 경우-

An Analysis on Volumetric Displacement of Gerotor Hydraulic Motor using Energy Conservation and Torque Equilibrium - Second Report: The Case of a Revolving and Rotating Inner Rotor -

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 함영복(한국기계연구원); 김대명((주)대화산기)" ]

It is difficult to analytically derive a volumetric displacement formula for a gerotor hydraulic motor due to the complexity of the geometric shape of its gear lobes. This work proposes an analytical method for the volumetric displacement, a relatively easy method based upon two physical concepts: conservation between hydraulic energy and mechanical shaft energy, and torque equilibrium for the rotor’s motion. The first research using these concepts was conducted on inner and outer rotors rotating with respect to each rotor axis. This work represents the second report conducted on an inner rotor revolving as a planetary motion on the stationary outer rotor. The formula equations regarding the volumetric displacement and flow rate are derived, and the proposed formula about the volumetric displacement is proven to be the same as another analytical displacement formula: the so-called vane length method. From the formula, volumetric displacement is calculated for an example geometry of the gear lobes. The resultant displacement is confirmed to be the same as the value calculated from the chamber volume method. The proposed analytical formula can be utilized in the analysis and design of gerotor hydraulic motors. Because it is based on torque equilibrium, this formula can provide a better understanding of torque performance, such as torque ripple, in designing a gerotor type motor.

기계공학

null

kci_detailed_000118.xml

ART001932919

oai_dc

DLC 코팅에 의한 사판식 피스톤 펌프의 저속 영역 동력 손실 개선

Performance Improvement of a Swash Plate Type Piston Pump in the Low-Speed Range by a DLC Coating

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "홍예선(한국항공대학교); 김종혁(한국항공대학교); 이성렬(한국항공대학교)" ]

This paper details application of a DLC(Diamond Like Carbon)-coating to the swash plate and the ball joint of pistons that make sliding contact with the piston shoes of an axial piston pump. This process, aimed to reduce the frictional and leakage power losses of the hydrostatic piston shoe bearings at the low speed range. At lower speeds than 100rpm, the positive effects of the DLC-coating on the power loss reduction of the hydrostatic piston shoe bearings could be confirmed. These effects resulted in little improvement in volumetric efficiency of the test pump, but the mechanical efficiency could be raised by up to 5% at 100rpm; here, the DLC-coated swash plate played a more dominant role than the DLC-coated ball joint.

기계공학

null

kci_detailed_000118.xml

ART001932920

oai_dc

유전자 알고리즘과 콤플렉스법에 의한 고성능 유압휴즈의 최적 설계

Optimal Design of a Quick-Acting Hydraulic Fuse using Genetic Algorithm and Complex Method

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성래(건양대학교)" ]

The hydraulic fuse, which responds to the suddenly increased flow on rupture of a line and shuts off the fluid flow, would prevent large spillage of liquid. The quick-acting hydraulic fuse, which is mainly composed of a poppet, a seat, and a spring, must be designed to minimize the leaked flow and to prevent high collision speed between the poppet and seat during fuse operation on a line rupture. The optimal design parameters of a quick-acting hydraulic fuse were searched using the genetic algorithm and the complex method that are kinds of constrained direct search methods. The dynamic behavior of a quick-acting hydraulic fuse was researched using computer simulations that applied the obtained optimal design parameters.

기계공학

null

kci_detailed_000118.xml

ART001932933

oai_dc

가변 용적형 사판식 피스톤 펌프의 회전 속도 조절에 의한 정압 제어 소비 동력 절감

Reduction of Power Consumption for Constant Pressure Control of Variable Swash Plate-type Piston Pump by Varying the Pump Speed

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김종혁(한국항공대학교); 홍예선(한국항공대학교)" ]

This paper proposes a control scheme to reduce the power consumption of a variable displacement swash-plate type piston pump supplying oil to a valve-controlled hydraulic cylinder at constant pressure. Whenever flow rate demand was absent, the swash plate angle and the pump speed were changed to the minimum values required to compensate for the internal leakage flow. In response to command signals, the pump speed was changed in proportion to the absolute mean value of the speed component for position commands. At the same time, a pressure regulator was activated to maintain constant system pressure by precisely adjusting the pump speed with the swash plate angle fixed at the maximum. The conventional system consisting of a pressure-compensated variable displacement type pump is driven at a constant speed of 1,800rpm. By comparison, computer simulation and experimental results showed that idling power at stand-by status could be reduced by up to 70% by reducing the pump speed from 1,800rpm to 300rpm and the swash plate angle to the minimum.

기계공학

null

kci_detailed_000118.xml

ART001932925

oai_dc

유압식 굴삭기의 고효율 화에 관한 새로운 접근

A New Approach to the High Efficiency of Hydraulic Excavator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이용범(한국기계연구원 시스템신뢰성연구실)" ]

With recent oil price increases, the fuel efficiency of hydraulic excavators has become a serious issue. Researchers have considered weight lightening by high pressurization in order to improve the efficiency of the excavator and pump controlled actuation (PCA) and to reduce pressure loss of hybrid and valves using mechanical inertia. However, high pressurization is not very effective because the excavator operates at a low speed; a hybrid is inefficient because little accumulated inertial energy is accumulated; and PCA is ineffective because control precision and responsibility are low. In this study, a method to minimize air and gas in hydraulic oil has been presented as a simple and new way to increase hydraulic efficiency.

기계공학

null

kci_detailed_000118.xml

ART001932929

oai_dc

상용해석 툴을 이용한 소형 스크류 디캔터의 설계에 관한 연구

A Study on Design of Small Type Screw Decanter using Commercial Analysis Tool

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김용석(울산대학교); 김종태(신정뉴테크(주)); 양순용(울산대학교)" ]

This study suggests a small-sized screw decanter specialized for dredging sites. Generally, conventional screw decanters are composed of a cylinder and a cone. However, the suggested screw decanter simply has a cone based on a cone-type bowl structure. In this research, a commercial analysis tool is used to establish an optimal design for the bowl and the screw conveyor. Moreover, the base frame, where the main bearings that support the spindle of the bowl and the screw conveyor are installed, is optimally designed considering the weight of the rotating body and the deflection caused by the high centrifugal force. Furthermore, the natural frequency range of the spinning body, the bowl and the screw conveyor, is applied to this base frame; it is designed not to correspond to the resonance frequency range and achieves stability as a result. This study suggests an optimal design for the rotating body and the base frame of a screw decanter considering its vibration characteristics. Such a design will prevent overuse of materials and help to reduce the weight and volume—and the price—of a screw decanter.

기계공학

null

kci_detailed_000118.xml

ART001932913

oai_dc

Position control of Electro Hydraulic Actuator (EHA) using an Iterative Learning Control

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "도안녹치남(울산대학교); 우엔민트리(울산대학교); 박형규(울산대학교); 안경관(울산대학교)" ]

This paper presents the development of a compact position generator to be used for industrial purposes based on a pump controlled Electro-Hydraulic Actuator (EHA), which is closed-loop controlled by an embedded based Iterative PID controller. The controller is designed by combining the PID controller and the iterative learning scheme to perform tracking control for periodically desired references. Control algorithm is implemented on an embedded computer (AD 7011-EVA) which makes the implementation and application in industrial environments easier.

기계공학

null

kci_detailed_000118.xml

ART002080080

oai_dc

트랙터 자동변속기 되먹임 변속 제어기 설계

Feedback Shift Controller Design of Automatic Transmission for Tractors

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교); 정창도(타이코에이엠피); 박세하(타이코에이엠피유한회사)" ]

Nowadays automatic transmission equipped vehicles prevail in construction and agricultural equipment due to their convenience in driving and operation. Though domestic vehicle manufacturers install imported electronic controlled transmissions at present, overseas products will be replaced by domestic ones in the near future owing to development efforts over the past 10 years. For passenger cars, there are many kinds of shift control algorithms that enhance the shift quality such as feedback and learning control. However, since shift control technologies for heavy duty vehicles are not highly developed, it is possible to improve the shift quality with an organized control method. A feedback control algorithm for neutral-into-gear shift, which is enabled during the inertia phase for the master clutch slip speed to track the slip speed reference, is proposed based on the power transmission structure of TH100. The performance of the feedback shift control is verified by a vehicle test which is implemented with firmware embedded TCU. As the master clutch engages along the predetermined speed trajectory, it can be concluded that the shift quality can be managed by a shift time control parameter. By extending the proposed feedback algorithm for neutral-into-gear shift to gear change and shuttle shift, it is expected that the quality of the shift can be improved.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.001

kci_detailed_000118.xml

ART002080091

oai_dc

Surface Texturing에 의한 유압부품의 마찰저감

Surface Texturing in Hydraulic Machine Components for Friction Reduction

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "박태조(경상대학교); 김민규(경상대학교)" ]

In hydraulic machinery, the hydraulic fluid acts primarily as working fluid and secondarily as a lubricant. Hence, the viscous friction force acting on the sliding components should be reduced to improve the mechanical efficiency. It is now well known that the surface texturing is a useful method for friction reduction. In this study, using a commercial computational fluid dynamics (CFD) code, FLUENT, the lubrication characteristics of a surface textured slider bearing under high boundary pressure difference is studied. The streamlines, velocity profiles, pressure distributions, load capacity, friction force and leakage flowrate are highly affected by the film thickness ratio and the textured region. Partial texturing at the inlet region of the inclined slider bearing can reduce both friction force and leakage flowrate than in the untextured case. The present results can be used to improve the lubrication characteristics of hydraulic machinery.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.027

kci_detailed_000118.xml

ART002080086

oai_dc

평행주차를 위한 자동 조향 제어시스템 개발 및 성능평가

Development and Evaluation of Automatic Steering System for Parallel Parking

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이대현(충남대학교); 김용주(충남대학교); 김태형(LG전자); 정선옥(충남대학교); 최창현(성균관대학교)" ]

This research is conducted to develop an automatic steering system for parallel parking, and the performance of the system was evaluated by parallel parking a conventional vehicle. The automatic steering system consisted of MDPS (motor driven power steering) to control steering, ESC (electronic stability control) to acquire wheel speed, ultrasonic sensors to recognize the parking space, and a controller to communicate and handle data. The parallel parking process using the automatic steering control consisted of parking space recognition, parking path generation, and parking path tracking. The path for parallel parking was generated based on a kinematic model of a conventional vehicle, and a PI controller was used to control the steering angle for path tracking. Parallel parking using the automatic steering control was conducted according to vehicle speed conditions. The results show that the errors on the x-axis and y-axis were below 0.54 m and 0.14 m, respectively, and the error on the steering angle was less than 1°. Therefore, it is possible to implement parallel parking using an automatic steering control system for conventional vehicles.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.018

kci_detailed_000118.xml

ART002080081

oai_dc

e-4WD 시스템 개발

Development of electric Four Wheel Drive System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조희영(현대자동차 연구개발본부)" ]

e-4WD(Electric-4WD) system is a 4WD(4-Wheel Drive) System that can transform a car into a Hybrid System. e-4WD consists of a Motor, Inverter, Speed reducer and Clutch. The Motor, Speed reducer and Clutch are installed on the rear sub-frame as a chassis module type. The inverter is installed separately. Compared to a mechanical 4WD, the e-4WD system has many advantages. For example, the reduced number of drivetrain components makes better use of the space. Driving with a motor only at low speed improves fuel economy and reduces exhaust gas. Engine downsizing is available because the motor assists the engine. The performance of a conventional HEV(Hybrid Electric Vehicle) system can also be maintained. This paper proposes the specifications of components and the control logic for an e-4WD System. And the effect of the e-4WD system is proven using a test vehicle equipped with components under various test conditions.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.010

kci_detailed_000118.xml

ART002084799

oai_dc

서보밸브 스풀-슬리브 형상공차가 압력 정특성에 미치는 영향 연구

Effect of Spool-Sleeve Geometry on Static Pressure Characteristics of Servo Valves

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 손성회(금오공과대학교 기계시스템공학과); 함영복(한국기계연구원)" ]

This study studied how the clearance, overlap and mismatch errors of spool-sleeve affect the static pressure characteristics of a servo valve. A computer simulation model was established as a direct acting servo valve and a series of simulations was conducted for various values of clearance, overlap and mismatch errors. Pressure gain decreased as the clearance increased. The overlap also affects the pressure gain and was similar to the effect of clearance. Asymmetry of the pressure plot got worse and worse as the mismatch error increased.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.034

kci_detailed_000118.xml

ART002084815

oai_dc

굴삭기의 버킷 끝단 위치인식에 관한 연구

A Study on Position Recognition of Bucket Tip for Excavator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김재훈(두산인프라코어); 배종호(두산인프라코어); 정우용(두산인프라코어)" ]

The accurate calculation of bucket tip position has a large influence on showing the motion of an excavator on the display device of the excavator and controlling the excavator automatically. It is generally known that Inertial Measurement Unit (IMU) sensors are more accurate than accelerometer-based sensors while the boom, arm or bucket moves because additional forces beyond gravity add additional acceleration to the sensors. To prove the accuracy difference between the two types of sensors, a position recognition system using an accelerometer-based sensor and an IMU sensor is implemented on the excavator. The experimental results show that the system using the IMU sensor significantly reduces the position recognition error while bucket moves and additional force beyond gravity exists.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.049

kci_detailed_000118.xml

ART002084646

oai_dc

압력센서 개발을 한 탄소 나노 튜 기반 지능형 복합소재 왜 특성 연구

A Study on Piezoresistive Characteristics of Smart Nano Composites based on Carbon Nanotubes for a Novel Pressure Sensor

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성용(부경대학교); 김현호(부경대학교); 최백규(부경대학교 기계설계공학과); 강인혁(부경대학교 기계설계공학과); 이일영(부경대학교); 강인필(부경대학교)" ]

This paper presents a preliminary study on the pressure sensing characteristics of smart nano composites made of MWCNT (multi-walled carbon nanotube) to develop a novel pressure sensor. We fabricated the composite pressure sensor by using a solution casting process. Made of carbon smart nano composites, the sensor works by means of piezoresistivity under pressure. We built a signal processing system similar to a conventional strain gage system. The sensor voltage outputs during the experiment for the pressure sensor and the resistance changes of the MWCNT as well as the epoxy based on the smart nano composite under static pressure were fairly stable and showed quite consistent responses under lab level tests. We confirmed that the response time characteristics of MWCNT nano composites with epoxy were faster than the MWCNT/EPDM sensor under static loads.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2016.13.1.043

kci_detailed_000118.xml

ART001958309

oai_dc

전기 인버터 구동 수압 피스톤 펌프 시스템의 효율 성능에 관한 실험적 연구

An Experimental Study on the Efficiency of the Water Hydraulic Piston Pump System driven by an Electric Inverter

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 함영복(한국기계연구원); 박준형(휘닉스 PED 기술연구소)" ]

A water hydraulic pump is likely to have serious problems of high leakage, friction and low energy efficiency. A water hydraulic pump has commonly a fixed displacement type and its outlet flow is adjusted by controlling rotation speed of the pump, which can be implemented by using an electric inverter. This study aims to investigate energy efficiency of the water hydraulic pump system which is driven by an electric inverter. The study is based on the experimental results. The pump which is used in the study shows relatively good efficiency and low leakage, low friction as well. The reasons for the good performance of pump is also investigated.

기계공학

null

kci_detailed_000118.xml

ART001959268

oai_dc

초저온 볼밸브의 열 응력 및 유동해석

Thermal stress and Flow Analysis of a Cryogenic Ball Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동수(한국기계연구원 정보장비연구센터); 배상규(한국기계연구원); 이원희(한국기계연구원); 김현섭((주)싱크루트)" ]

The high pressure cryogenic ball valve is used to transfer the liquefied natural gas which temperature is -196℃, supplied pressure is 168kgf/㎠. In the present work, the temperature distribution and thermal deformation is calculated numerically. The CAE and CFD methods are useful to predict the thermal matter and the inner flow field of high pressure cryogenic ball valve. For this reason, to optimum design of the cryogenic ball valve, the theological behavior of the supplied LNG in a cryogenic valve has been studied. The governing equations are discredited and solved numerically by the finite-volume method and finite-element method. In this study, we designed the high pressure cryogenic ball valve that accomplishes zero leakage by elastic seal at normal temperature and metal seal at high temperature.

기계공학

null

kci_detailed_000118.xml

ART001959307

oai_dc

자동변속기용 비례제어 솔레노이드밸브 성능시험기 개발

A Development of Proportional Control Solenoid Valve Performance Tester for Automatic Transmission

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교); 이근호(한국기계연구원)" ]

The proportional control solenoid valves as well as the PWM solenoid valves operated by electric signal play an important role in the hydraulic system for automatic transmissions to improve the shift quality. However it is not generally available for the performance date because most of the automotive parts manufacturer don't release the specific test results, especially dynamic performance that is essential to design a shift control algorithm.

기계공학

null

kci_detailed_000118.xml

ART001959273

oai_dc

마이크로 솔레노이드의 해석 및 개발

Analysis and Design of Micro Solenoid

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동수(한국기계연구원 정보장비연구센터)" ]

Recently, the on-off solenoid valves have been focused on core technology in the fields of the production line of semi-conductor chips and the micro fluid chips for bio-medical applications. A key characteristics for on-off solenoid valve, operated by compressed air, are high speed response and great repeatability. Indeed, it is also important to keep the pressure on the cross-sectional area of the poppet to be constant regardless of the fluctuation of the pressure exerted on the ports. In this study, we have designed and analysed the high-speed and high flow rate on-off solenoid valve using the analogy of equivalent magnetic circuit and Finite Element Method(FEM) respectively. In case of poppet, flow characteristics was analyzed by the variation of poppet and it was able to display flow field by changing the location of the poppet. Also, we verified possibility of the design through the static and dynamic pressure and the 3D simulation using distribution curve of the force by working the front poppet.

기계공학

null

kci_detailed_000118.xml

ART001995341

oai_dc

다운더홀(DTH) 해머의 모델링 및 실험

Modelling and Test of Down-the-Hole Hammer

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "황운규(에버다임 선행개발팀)" ]

Research and development of mineral resource related products has progressed with the increased need to develop mineral resources. The DTH hammer is one a resultant product. However, due to particular work conditions of underground drilling, it is difficult to obtain direct data on the DTH Hammer. A DTH drill rig requires a lot of money and time for actual testing. This thesis aimed to resolve this problem by using CAE. First, the structure of the DTH hammer and the movement was analyzed. Next, a standard model based on simulation was proposed and then experimentation and comparison verification was conducted. In addition, the verified models were applied to products of various sizes, and the models used in simulation were compared by conducting field tests.

기계공학

null

kci_detailed_000118.xml

ART001995332

oai_dc

파랑의 수평운동을 이용한 파력발전장치 개발

Development of Wave Power Generator using Horizontal Motions of the Wave

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "황성수(전남대학교); 박일흠(전남대학교); 이동수(SEA TECH R&D Co.,); 양경욱(전남대학교)" ]

In this study, we suggested the wave power generator using horizontal motions of the wave for use in the coastal sea. The length of the horizontal movement of the wave in the vicinity of the sea surface is larger than the length of the vertical reciprocating movement of the wave, hence the proposed device has a wave power transmission plate. In addition, because the motion of the wave is maximum to the sea surface, by arranging the buoyancy tanks at the top of the wave power transmission plate, it is always capable of vertical movement in accordance with the sea surface. To confirm the usefulness of the proposed wave power generator, we constructed a mathematical model of the wave power generator and carried out simulation using bondgraph. Furthermore, the efficiency was verified by measuring the degree of electrical energy production through a preliminary experiment.

기계공학

null

kci_detailed_000118.xml

ART001995338

oai_dc

저속에서 피스톤 슈 내부 보조 링의 윤활 효과 분석

Investigation of the Tribological Effects of the Auxiliary Inner Ring for Piston Shoes at Low Speeds

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 김종혁(한국항공대학교); 홍예선(한국항공대학교); 김병곤(유원산업); 문진삼(유원산업); 문준혁(유원산업)" ]

In order to design a swash plate type pump for electro-hydrostatic actuators the performance of the hydrostatic piston shoe bearings in the low speed range needs to be examined, since the pump operates frequently at low speeds, compensating for position control errors as a control element. As a common practice, piston shoes are equipped with inner rings as an auxiliary element to enhance their tribological performance. In this paper, the effects of the inner rings of the piston shoes on the frictional loss and leakage flow rate were investigated, where three piston shoe models, with different inner ring shapes and different inlet orifice sizes, were integrated. The test results showed that a large inner ring and small inlet orifice were advantageous for reducing both the frictional loss and leakage flow rate; this could also be confirmed by computational analyses.

기계공학

null

kci_detailed_000118.xml

ART001995329

oai_dc

정유압구동기(EHA)의 모델링과 제어기 설계

Modeling and Controller Design of an Electro-Hydrostatic Actuator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "허준영(한국기술교육대학교); 김현호(부경대학교); 이일영(부경대학교)" ]

Recently, the Electro-Hydrostatic Actuator(EHA) has been developed as a result of research on energy saving. EHA is usually composed of a direct driven pump from an electric motor and is available to control cylinder displacement or velocity with high efficiency. In addition, it has the advantage of compactness, minimum leakage and availability of decentralized control. In this study, an EHA system was designed to decrease the path tracking error and manufactured for test. The linearization method provided in AMESim software was used to derive the model of EHA system. The derived model was applied to design the PI-D controller to effectively overcome the disturbance. The effectiveness of this controller was verified by further testing.

기계공학

null

kci_detailed_000118.xml

ART001995345

oai_dc

메인 컨트롤밸브의 해석모델 개발 및 검증

Development and Verification of Analytical Model of a Main Control Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동명(가천대학교); 이정민(창원대학교); 정원지(창원대학교); 장주섭(가천대학교)" ]

In order to control the actuators of hydraulic machinery such as excavators, various control valves are typically assembled in a single block. Such a control block is called a main control valve(MCV). In this paper, we analyzed the working principle and the particular purpose of the design of all valves included in the MCV system. To Examine the reliability of the analysis model, the pressure drop of the MCV at each port was measured. The authors developed an analytical model of the control valve(main spool, load poppet, pressure relief, make up, and regeneration). The authors considered the notch shape of the spool while developing the analytical models of the main spool valve. Most importantly, at the stage before the analysis model was applied in the design tuning, the reliability was ensured by comparing the analysis results with the test results. This paper showed a process of developing an analysis model that can be utilized in the design and tuning stages.

기계공학

null

kci_detailed_000118.xml

ART001995335

oai_dc

AC서보모터-볼스크루 구동 사출장치의 힘 동기제어

Force Synchronizing Control for AC Servomotor-Ball Screw Driven Injection Unit

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조승호(홍익대학교)" ]

This paper focuses on the issue of force synchronizing control for the injection servomechanism of injection molding machines. Prior to the controller design, a virtual design model was developed for the injection mechanism with an AC servomotor-ball screw. A synchronizing controller is designed and combined with the PID control to accommodate the mismatches between the real plant and the linear model plant used. Due to the plant uncertainty, the stiffness and the damping of the mechanism were considered. From the tracking control simulations based on the virtual design model, it is shown that a significant reduction in force synchronizing error is achieved through the use of a proposed control scheme.

기계공학

null

kci_detailed_000118.xml

ART001995340

oai_dc

Development of the Flexible Observation System for a Virtual Reality Excavator Using the Head Tracking System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "레광환(울산대학교); 정영만(울산대학교); 웨치탄(울산대학교); 양순용(울산대학교)" ]

Excavators are versatile earthmoving equipment that are used in civil engineering, hydraulic engineering, grading and landscaping, pipeline construction and mining. Effective operator training is essential to ensure safe and efficient operating of the machine. The virtual reality excavator based on simulation using conventional large size monitors is limited by the inability to provide a realistic real world training experience. We proposed a flexible observation method with a head tracking system to improve user feeling and sensation when operating a virtual reality excavator. First, an excavation simulator is designed by combining an excavator SimMechanics model and the virtual world. Second, a head mounted display (HMD) device is presented to replace the cumbersome large screens. Moreover, an Inertial Measurement Unit (IMU) sensor is mounted to the HMD for tracking the movement of the operator's head. These signals consequently change the virtual viewpoint of the virtual reality excavator. Simulation results were used to analyze the performance of the proposed system.

기계공학

null

kci_detailed_000118.xml

ART001908755

oai_dc

Modeling and Performance Investigation of Forklift Transmission Control Valve System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "딩광청(울산대학교); 안경관(울산대학교); 윤장원(ms정밀)" ]

In forklifts, the machine performance is largely depended on the transmission performance. The aim of this paper is to develop a complete model of transmission control valve (TMV) system of a typical forklift using AMESim simulation tool. By using the developed TMV model, it becomes easy to investigate the system concept, working principle, and performance. In addition, an optimization on the TMV structure can be achieved by using this model with tunable parameters. Simulations have been carried out in a comparison with the actual experiments to verify the model.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.001

kci_detailed_000118.xml

ART001908756

oai_dc

A Ship Berthing System Design by Cooperating with Tugboats and Dampers

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "안민트란(부경대학교 대학원 제어기계공학과); 지상원(부경대학교); 김영복(부경대학교)" ]

Everyday about 90% of cargos are delivered by ships, and thousands of vessels enter and depart the international container harbors such as Shanghai, Singapore, Hong Kong, Busan, Rotterdam, etc. Maneuvering at harbor is known as the most sophisticated and difficult procedure, because the effectiveness of actuators during low speed berthing is reduced. In this paper, a new berthing method is discussed. Tugboats are combined with damper systems to ensure safe berthing. A mathematical model describing the interaction between unactuated ship, tugboats and damper systems is presented. An optimal controller is designed to maneuver the ship without oscillation and overshoot. MCL (Marine Cybernetics Lab) model ship is used to evaluate the efficiency of the proposed approach through MatLab simulation.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.007

kci_detailed_000118.xml

ART001908757

oai_dc

드리프터의 유압시스템 해석모델 개발 및 신뢰성 검토

Development of drifter’s hydraulic system model and its validation

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "노대경(가천대학교); 장주섭(가천대학교); 김흥섭(한국기계연구원); 박승현((주)필엔지니어링); 서자호(한국기계연구원)" ]

The goal of this study drifter is to understand the operating mechanism of a drifter and to suggest a reliable analysis model which can be used for evaluating the drifter’s performance from the viewpoint of impact frequency and energy. For this, the working principle of drifter and functions of its main components were analyzed, and a simulation model was developed based on the analysis. The model was validated using experimental tests on a test-bench. A comparative study of simulation and experimental results indicated that the suggested model accurately represents the real drifter system in terms of impact frequency and impact energy per blow.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.014

kci_detailed_000118.xml

ART001908758

oai_dc

A Study of Stability for Field Robot using Energy Stability Level Method

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "웨치탄(울산대학교); 레광환(울산대학교); 정영만(울산대학교); 양순용(울산대학교)" ]

In this research, the energy stability level method is used for examining the stable state of Field Robot under effects of swing motion, at particular postures of manipulator, and terrain conditions. The energy stability level is calculated by using the dynamic models of Field Robot, subjected to the concept of equilibrium plane and support boundary. The results, simulated by using computing program for estimating the potential overturning of Field Robot, supply useful predictions of stability analysis for designers and operators.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.022

kci_detailed_000118.xml

ART001908759

oai_dc

Development of a Multi-Absorbing Wave Energy Converter using Pressure Coupling Principle

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "도황팅(울산대학교); 누엔밍치(울산대학교); 판콩빙(울산대학교); 이세영(울산대학교); 박형규(울산대학교); 안경관(울산대학교)" ]

This paper proposes a multi absorbing wave energy converter design, in which a hydrostatic transmission is used to transfer wave energy to electric energy. The most important feature of this system is its combination of the pressure coupling principle with the use of a hydraulic accumulator to eliminate the effects of wave power fluctuation; this maintains a constant speed of the hydraulic motor. Tilt motion of a floating buoy was employed as the power take-off mechanism. Furthermore, a PID controller was designed to carry out the speed control of the hydraulic motor. The design offers some advantages such as extending the life of the hydraulic components, increasing the amount of energy harvested, and stabilizing the output speed.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.031

kci_detailed_000118.xml

ART001908760

oai_dc

HST 중립밸브의 해석모델 개발 및 설계변수 민감도 분석

Analysis Model Development and Sensitivity Analysis on Design Parameters of the Neutral Valve for HST

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김동명(가천대학교); 장주섭(가천대학교); 김수철(LS엠트론)" ]

The neutral valve for controlling the HST is one of the important valves for the vehicle control. Neutral valve takes a role of blocking or transmitting power to the vehicle. The operating principle of the neutral valve was developed through the analysis model. We also investigated the logical validity by analyzing the results of the analysis model. The analysis model was developed by using SimulationX witch is commercial software. The number of holes in the piston was selected as a variable initial compression of the spring, and the magnitude of the pressure pulsations and the diameter of the orifice for the sensitivity analysis were performed to design sensitivity analysis of the neutral valve.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.041

kci_detailed_000118.xml

ART001908761

oai_dc

자동변속기 클러치 충전제어 파라미터의 실험적 특성분석

Experimental Analysis of Clutch-Fill Parameters for Automatic Transmission

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교); 박동훈(시스톤 테크놀로지스)" ]

Clutches are an integral part of the automatic transmission for changing gears. Modern automatic transmissions make extensive use of wet multiple-disc clutches employing hydraulic actuation mechanism with electronic control. Although nowadays, highly advanced shifting algorithm implements the superior shift quality and transmission efficiency, its performance should be based on smooth, reliable engagement with a reasonably durable friction material as well as stable clutch piston dynamics. Particularly, clutch filling control is the crucial part of shifting process because only the open-loop control is available due to the lack of measurement. In this paper, the effect of clutch-fill control parameters on clutch piston dynamics is experimentally investigated by using clutch piston test equipment which enables the clutch piston to actuate similar to real shifting conditions. The experimental analysis results can be expected to be utilized for the calibration of proportional solenoid valve as reference current profile data in vehicle test.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2014.11.3.047

kci_detailed_000118.xml

ART002139524

oai_dc

제어밸브의 유량특성에 따른 에어스프링의 성능 변화

Effect of Control Valve Flow Rates Characteristics on the Performance of an Air Spring

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "한승훈(부경대학교); 장지성(부경대학교); 지상원(부경대학교 기계시스템공학과)" ]

This study describes the effect of the critical pressure ratio of a control valve on the performance of an air spring system composed of an air spring, auxiliary chamber, control valve and mass in order to suggest a more efficient design for an air spring system. The critical pressure ratio of the control valve is assumed to have a fixed value, but the critical pressure ratio of the control valve is known to have various values between 0.05 and 0.6, and the effect of the variation of the critical pressure ratio on the performance of the air spring system has not yet been reported. The analysis derives nonlinear and linear governing equations of the air spring system, including the critical pressure ratio of the control valve. This simulation study is presented to show that the impedance and transmissibility characteristics of the air spring system change due to variations in the critical pressure ratio of the control valve as well as its sonic conductance. As a result, the critical pressure ratio of the control valve should be maintained as large as possible to improve the vibration isolation characteristics of the air spring system.

기계공학

null

kci_detailed_000118.xml

ART002139482

oai_dc

상온기체 블로우다운 방식을 사용한 유도무기용 유압식 구동장치의 공압부에 대한 모델링 및 시뮬레이션

Modeling and Simulation of the Pneumatic Part in a Cold Gas Blow-Down Type Hydraulic Actuation System for a Missile

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "박희승(국방과학연구소(대전))" ]

A cold gas blow-down hydraulic actuation system is widely used in missiles that require an actuation system with a fast response time under a limited space with a short operating time and large loads on the actuators. The system consists of a pneumatic part that supplies the regulated high-pressure gas to a reservoir, and a hydraulic part that supplies pressurized hydraulic oil to the actuators by the pressurized gas in the reservoir. This paper proposes a mathematical model to analyze and simulate the pneumatic part of an actuation system that supplies the operating power to the actuators. The mathematical model is based on the ideal gas equation and also considers the models for heat transfer. The model is applied to the pressure vessel and the gas part of the reservoir, and the model for the pneumatic part is established by connecting the two models for the parts. The model is validated through a comparison of the simulation results with the experimental results. The comparison shows that the suggested model could be useful in the design of the pneumatic part of a cold gas blow-down type hydraulic actuation system.

기계공학

null

kci_detailed_000118.xml

ART002142402

oai_dc

양방향 구동 사판식 액시얼 피스톤 펌프의 밸브 플레이트 노치 설계에 관한 연구

A Study on Design of Notches in Valve Plate of Swash Plate Type Axial Piston Pumps Operated Bi-directionally

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "최세령(부경대학교); 이일영(부경대학교); 한성민(세원셀론텍(주)); 신정우(세원셀론텍(주))" ]

Flow and pressure ripple in swash plate type piston pumps is largely dependent on the design of notches(silencing grooves) in the valve plate. In uni-directional pumps, the basic design concept for notches in the valve plate could be said to be established. It is easily deduced that the design concept for notches in uni-directional pumps can not be simply applied to bi-directional pumps requested for EHA(electric hydrostatic actuators). To carry out systematic research on technological issues regarding notch applications to bi-directional piston pumps, five notch designs are devised. The effects of the notch designs on the characteristics of the pump are investigated by numerical simulations and experiments. Through this study, basic concepts about notch design for bi-directional piston pumps are suggested.

기계공학

null

kci_detailed_000118.xml

ART002141513

oai_dc

비례적분+이중적분 제어기를 이용한 정상상태 응답 개선

Improvement of Steady State Response Using PI+Double Integral Controller

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교)" ]

The performance characteristics of a dynamic control system are evaluated according to the transient and steady-state responses. The transient performance is the controllability of the output for the tracking of the reference or the ability to reduce or reject the effects of unwanted disturbances; alternatively, the steady-state performance is represented by the magnitude of the control error at the steady state. As the effects of the two performances on each other are reciprocal, a controller design that shows a zero steady-state error for the ramp input is uncommon because of the challenge regarding the achievement of an acceptable transient response. This paper proposes a PI+double-integral controller for the elimination of the steady-state error for the ramp input while a sound transient performance is maintained. The control-gain design procedure is described by the second-order response for the step input and the response of the error dynamics for the ramp input. The PI+double-integral controller is designed for the first-order transfer function that is derived from a system identification with the open-loop experiment data of the dc-motor. The simple structure of the proposed controller enables the adoption of a low-end microcontroller for the implementation of a real-time control. The experiment results show that the control performance is as effective as that of the simulation analysis for the operating point of linear system; furthermore, the PI+double-integral controller can be conveniently applied to the control system, which is desirable for the improvement of the steady-state error.

기계공학

null

kci_detailed_000118.xml

ART002141508

oai_dc

근궤적과 수동 조정에 의한 직접 구동형 서보밸브의 PID 제어기 및 미분피드백 이득 설계

PID Controller and Derivative-feedback Gain Design of the Direct-drive Servo Valve Using the Root Locus and Manual Tuning

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성래(건양대학교)" ]

The direct-drive servo valve(DDV) is a kind of one-stage valve because the main spool valve is directly driven by the dc motor. Since the DDV structure is simple, it is less expensive, more reliable, and offers a reduced internal leakage and a reduced sensitivity to fluid contamination. The control system of the DDV is highly nonlinear due to a current limiter, a voltage limiter, and the flow-force effect on the spool motion. The shape of the step response of the DDV-control system varies considerably according to the magnitudes of the step input and the load pressure. The system-design requirements mean that the overshoots should be less than 20%, and the errors at 0.02s should be less than 2%, regardless of the reference-step input sizes of 1V and 5V and the load-pressure magnitudes of 0MPa and 20.7MPa. To satisfy the system-design requirements, the PID-controller parameters of , and , and the derivative-feedback gain of are designed using the root locus and manual tuning.

기계공학

null

kci_detailed_000118.xml

ART002141529

oai_dc

이중 EHA의 제어 특성 개선

Control-performance Improvement of Dual EHAs

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 홍예선(한국항공대학교)" ]

For this paper, the position-control performances of dual EHA(electro-hydrostatic actuator) systems were investigated according to two cases wherein the double-rod- and single-rod-type hydraulic cylinders were combined. Since the control performance is significantly dependent on the load conditions including external forces such as the inertia load, it is proposed here that the two sub-EHAs are driven by separate position and force controllers, instead of two identical position controllers. According to the simulation results, the best performance was achieved by the position-controlled single-rod-type EHA that was combined with a force-controlled double-rod-type EHA. As the force-controlled double-rod-type EHA compensated for the external loads on the position-controlled single-rod-type EHA, the position-control performance was not influenced by external forces including the inertia load. In addition, the position-controlled single-rod-type EHA contributed to the enhancement of the damping ratio by absorbing the pressure peaks through its internal accumulator. Due to the symmetrical piston areas, the double-rod-type EHA is more suitable for force control than the single-rod- type EHA.

기계공학

null

kci_detailed_000118.xml

ART002142420

oai_dc

비례제어 솔레노이드 액추에이터의 응답성 향상 연구

A Study on Response Improvement of a Proportional Solenoid Actuator

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "윤소남(한국기계연구원); 함영복(한국기계연구원); 박중호(한국기계연구원)" ]

This paper presents a control method for the performance improvement of a proportional solenoid actuator using a Pulse Width Modulation (PWM) signal. It is very difficult to obtain excellent response performance from a proportional solenoid actuator using a simple proportional controller with no PWM signal or dither because the mass and structure of a proportional solenoid actuator changes according to the application target, friction force in the proportional solenoid tube, operating force and displacement range. To solve the above problems, first, a controller with a PWM function for experimenting with attraction force characteristics was designed and manufactured. Secondly, an experimental setup for solenoid performance measurement with a force sensor and a displacement sensor was also manufactured. The attraction force characteristics according to the frequency and duty ratio variations of a PWM signal were tested and the relationships among the frequency, duty ratio, plunger mass and friction characteristics were analyzed. Finally, response characteristics improvements for proportional solenoid actuators are discussed.

기계공학

null

kci_detailed_000118.xml

ART002142432

oai_dc

건설기계의 에너지 효율 제고를 위한 비-하이브리드 신기술에 관한 리뷰

A Review on New Non-hybrid Technologies to Improve Energy Efficiency of Construction Machineries

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조중선(창원대학교)" ]

New non-hybrid approaches to improve energy efficiency of construction machineries are reviewed in this paper. Hydraulic systems are classified into four classes according to Backé’s classification and commercially promising new technologies are carefully chosen in each class. IMV, 3-Line CPR, Closed Circuit Displacement Control of Differential Cylinder, and Throttle-less Secondary Control are chosen as representative non-hybrid new technologies. Key principle of each technology is explained and representative references which run through each technology are selected. Advantages and weaknesses of each technology are discussed and compared from the view point of construction machinery manufacturers.

기계공학

null

kci_detailed_000118.xml

ART002110129

oai_dc

2-방향 카트리지 밸브 기반 로직회로에 의한 사출성형기의 형체력 제어

Clamping force control of injection molding machine using 2-way cartridge valve based logic circuit

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조승호(홍익대학교)" ]

The present study deals with the issue of clamping force control of an injection molding machine using 2-way cartridge valve based logic circuit. The operating principle for the cartridge valve is described with its construction and static opening behavior. Basic module circuits are designed first and analysed according to the basic functions. Then they are combined with a virtual design model for the clamping mechanism to simulate the control performance of the overall system. The backlash inherent in the mechanism is considered while evaluating the time-delay in the process of clamping force build-up. The effects of a couple of design parameters in backlash, i.e. , interval and stiffness have been demonstrated in the time-domain.

기계공학

null

kci_detailed_000118.xml

ART002109839

oai_dc

지게차의 주관적 음질평가와 Zwicker 음질지수의 상관관계 및 전달경로분석법(OTPA)을 활용한 음질 기여도 분석

A Study on Contribution Analysis using Operational Transfer Path Analysis based on the Correlation between Subjective Evaluation and Zwicker's Sound Quality Index for Sound Quality of Forklifts

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김범수(현대중공업 건설장비 신뢰성평가부); 양순용(울산대학교)" ]

Recently, drivers have begun to regard comfort in the cabin as one of the most important factors in construction equipment like forklifts. Accordingly, it has become more important to design a forklift cabin with a better sound quality as well as lower sound level, which can make a driver more comfortable. In this paper, the correlation between subjective evaluation and Zwicker’s sound quality index was analyzed through a blind test by a few workers in forklifts and other construction equipment in several countries. Correlation analysis showed that Loudness and Sharpness were ranked in sequence, and tendencies were different from country to country. Also, contribution analysis for Loudness and Sharpness using operational transfer path analysis (OTPA), which is widely used in the field of noise, vibration, and harshness (NVH), was performed. However, Loudness and Sharpness cannot be used with OTPA directly because there are no linear relationships between the sources and receivers. In this paper, both are calculated by applying the DIN 45631 method with a contribution rate (%) of 1/3 Octave Sound Pressure Level by OTPA method in addition to considering spectral masking.

기계공학

null

kci_detailed_000118.xml

ART002109862

oai_dc

인공 신경회로망을 이용한 전자비례 감압밸브의 솔레노이드 형상 최적화

Optimization of Design Parameters of a EPPR Valve Solenoid using Artificial Neural Network

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "윤주호(울산대학교); 웬민냣(울산대); 이현수(울산대학교); 윤장원(울산대 기계공학부 유공압 및 기계지능 연구실); 김당주((주) 대호하이드로릭); 이동원((주) 대호하이드로릭); 안경관(울산대학교)" ]

Unlike the commonly used On/Off solenoid, constant attraction force which is independent of plunger displacement is a considerably important characteristic to proportional solenoid of the EPPR Valve. Attraction force uniformity is mainly affected by the internal shape design parameters. Due to a number of shape design parameters, the optimal parameter values are very complex and time consuming to find by trial and error method. Much research has been conducted or are still in progress to find the optimal parameter values by applying various optimization techniques like Genetic Algorithm, Evolution Strategy, Simulated Annealing, or the Taguchi method. In this paper, the design parameters which have primary effects on the attraction force uniformity and the average attraction force are decided by main effects analysis of Design of Experiments. Optimal parameter values are derived using finite-element analysis and a neural network model.

기계공학

null

kci_detailed_000118.xml

ART002110125

oai_dc

배관 압력을 이용한 서보밸브 정적 특성에 관한 실험적 연구

An Experimental Study on Static Characteristics of Servo Valves using Transmission Line Pressures

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 주별진(Dong Yang Industrial Co.,LTD. Top Run R&D Center, Korea); 윤소남(한국기계연구원)" ]

The conventional technique to measure the hysteresis and the null of servo valves is defined in ISO 10770-1 and based on load flow signal of the servo valve. A new technique based on the transmission line pressures is suggested in this study. The new measuring method was verified through a series of experiments. No hysteresis was observed between the spool displacement and the transmission line pressures, load pressure or each chamber pressure. Some hysteresis was observed between valve input and pressures, which was found to be the same as those of load flow and spool displacement for the valve input. By using the chamber pressures, the hysteresis and the null are easier to measure than the load pressure or differential pressure between those two chamber pressures because the chamber pressures showed sharp edges.

기계공학

null

kci_detailed_000118.xml

ART002109832

oai_dc

비대칭 이중화 EHA의 동기 제어

Synchronous Control of an Asymmetrical Dual Redundant EHA

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성렬(한국항공대학교 대학원 항공우주 및 기계공학과); 홍예선(한국항공대학교)" ]

In this paper, an elementary force fighting problem was investigated. The problem is encountered when a double-rod type EHA(electro-hydrostatic actuator) is combined with a single-rod type EHA to build a redundant actuator system with synchronized motion. When the rod-side chambers of the two different types of EHAs have the same effective piston areas and are simultaneously pressurized by an external load, the two EHAs behave identically, sharing the external load equally. However, when the piston head-side chamber of the single rod type EHA, having a larger effective area than the rod-side chamber, is pressurized by the external load, an abnormal force fighting between the two EHAs occurs, unless their pump speeds are properly decoupled. In this study, the output drive forces of each EHA were obtained from the cylinder pressure signals and applied to the position control for each EHA to maintain the balance between their pump speeds. Adding minor force difference feedback loops to the position control, the force fighting phenomena could be eliminated and steady state synchronization errors were reduced. The power consumption of the pumps also could be remarkably reduced, avoiding unnecessarily high load pressures to the pumps.

기계공학

null

kci_detailed_000118.xml

ART002109838

oai_dc

농업용 트랙터의 프론트 로더 충격 저감을 위한 유압 회로의 설계 개선

Improved Design of Hydraulic Circuit of Front-end Loader for Bump Shock Reduction of an Agricultural Tractor

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조봉진(서울대학교 바이오시스템공학); 안성욱(서울대학교); 이창주(서울대); 윤영환(J&F Solution); 이수성(태성공업); 김학진(서울대학교)" ]

A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements to mechanize routine agricultural tasks. When the FEL is used with a loaded bucket, careful operation is required to maintain safety and avoid spillage when the tractor passes a bump because a change in the gravity center of the tractor due to varied loadings can affect the stability of the tractor. Use of a boom suspension system consisting of accumulators and orifice dampers can be instrumental in reducing pitching vibrations while increasing the handling performance of the FEL-mounted tractor. The objective of this research was to reduce bump shocks by adding an orifice and a flow control valve to the original hydraulic circuit composed solely of accumulators. A simulation study was performed using the SimulationX program to investigate the effects of an accumulator and an orifice-throttle damper on bump shocks. Results showed that the peak pressure on a boom cylinder and the vertical acceleration of a bucket were significantly affected by use of both an accumulator and an orifice damper. In a field test conducted with a 75-kW tractor, the peak pressure of the boom cylinder, and the root mean square (RMS) vertical acceleration of the bucket and seat were reduced by on average, 23.0, 42.2, and 44.9% respectively, as compared to those measured with the original accumulator system, showing that an improved design for the accumulator hydraulic circuit can reduce bump shocks. Further studies are needed to design a tractor suspension system that includes the effects of cabin suspension and tires as well as dynamic analysis.

기계공학

null

kci_detailed_000118.xml

ART002109841

oai_dc

보행 로봇을 위한 서보밸브 구동 유압 액추에이터의 특성 분석

A Study of Hydraulic Actuator Based On Electro Servo Valve For A Walking Robot

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조정산(한국생산기술연구원 로봇그룹)" ]

This paper describes of a mathematical and real experimental analysis for a walking robot which uses servo valve driven hydraulic actuator. Recently, many researchers are developing a walking robot based on hydraulic systems for the difficult and dangerous missions such as walking in the rough terrain and carrying a heavy load. In order to design and control a walking robot, the characteristics of the hydraulic actuators in the joint through the view point of walking such as controllability and backdrivability must be analyzed. A general mathematical model was used for analysis and proceeds to position and pressure changes characteristic of the input and backdrivability experiment. The result shows the actuator is a velocity source, had a high impedance, the output stiffness is high in contact with the rigid external force. So stand above the controller and instruments that complement the design characteristics can be seen the need to apply a hydraulic actuator in walking robot.

기계공학

null

kci_detailed_000118.xml

ART001822559

oai_dc

유압 윈치를 이용한 선박 자동 계선법

Proposition of Automatic Ship Mooring Using Hydraulic Winch

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "허정규(전남대학교); 양경욱(전남대학교)" ]

연구는 선박 계선 안정성을 확보하는 방법으로 선박의 상갑판에 위치한 유압 윈치를 이용하는 방법을제안하였으며, 제안한 선박 계선 장치를 시뮬레이션하였다. 시뮬레이션을 통하여 선박 무게의 증감이 계선 속도와 횡동요 현상에 영향을 주고, 선미 종경사가 발생했을 경우에는 선박 평행 유지와 선수 동요 현상에영향을 미치며, 계선 시점에서는 선박의 정지 마찰력영향을 고려해야 함을 밝혔다. 균등한 선박 무게의증가도 초반부의 계선력 크기에 영향을 미치지만, 선박 관성(타력)이 발생하기 시작하면 유체 저항력은상쇄된다는 것도 확인할 수 있었다. 또한, 선박 계선안정성에 크게 영향을 미치는 횡동요와 선수동요 현상은 종경사 상태에서 관성모멘트의 영향으로 심화될수 있기 때문에 초기 계선력 결정에 유의해야 할 것으로 판단된다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.014

kci_detailed_000118.xml

ART001822561

oai_dc

전기 피드백 직동형 서보 밸브에 관한 역 분석

Reverse Analysis on a Direct Dive Servo Valve with Electric

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 안희욱(금오공과대학교)" ]

본 연구에서 LVDT 스풀변위 피드백 기능을 가지는 직동형 서보 밸브에 관하여 역분석 (reverse analysis)을 수행하였으며, 주요한 결과는 다음과 같이 요약된다. 1) 스풀 복귀 스프링의 강성이 매우 높고 선형 힘모터의 전류의 수준 또한 1000mA 범위로 높다. 2) 스풀 스프링의 강성에 비교하여 스풀 질량은상대적으로 작으며 스풀질량–스프링계의 고유 주파수는 195 Hz로 매우 높다. 3) 비례⋅적분(PI) 제어 방법과 속도⋅가속도 피드백이 서보 증폭기에 적용되었다. 적분기 이득은 일반적인 PI 제어기의 적분 이득보다 훨씬 크다. 적분 이득이 매우 큰 경우에 시스템의 안정성이 떨어질 가능성이 높은데, 매우 큰 적분 이득과 시스템의 안정성을 향상시키기 위해 속도 ⋅가속도 피드백이 적용된 것으로 보인다. 4) 선형 모터의 구동 전류를 생성하는 부분에서비교적 정밀도가 떨어지는 PWM 제어방법이 사용되고 있지만 전류 피드백이 적용되고 있어서 선형 힘모터의 정밀한 전류 구동을 가능하게 한다.  ×  정도의 큰 적분기 이득은 전류 피드백 루프 안에서사용되는데, 전류 피드백 루프 전체의 전달함수는 일정한 비례이득의 비례제어로 생각할 수 있다. 즉, 단순한 전압-전류변환기로 간주 될 수 있다. 5) 선형 힘 모터는 자기 히스테리시스 특성을 가지는데, LVDT 전기 피드백은 히스테리시스 효과를보상해 줌으로써 서보 밸브의 출력 신호인 스풀 변위와 유량, 압력에서는 히스테리시스 효과를 거의 완벽하게 제거한다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.022

kci_detailed_000118.xml

ART001822572

oai_dc

직접 제어 방식을 적용한 소형 지게차 변속 시스템에 관한 연구

A Study on Applying the Direct Control Method for Small Forklift Transmission System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정영만(울산대학교); 임구(울산대학교); 양순용(울산대학교)" ]

본 논문에서는 소형지게차의 메인 컨트롤 밸브를직접방식으로 개발하고 비례제어 밸브를 통해 변속충격과 출발성능을 개선하는 연구를 하였다. 본 연구의 결과는 다음과 같다. (1) 파일럿 제어 방식의 MCV를 직접 제어 방식으로 개발하였다. (2) 비례제어 밸브를 제어 할 수 있는 임베디드 시스템을 개발하였다. (3) 변속감도와 출발성능을 개선하기 위해 입력 프로파일의 변화에 따른 Fill구간, Hold구간, Ramp구간의 실차 테스트를 수행하였다. (4) 입력 프로파일의 각 구간이 변속충격과 출발성능에 미치는 영향을 파악하였다. 향후 변속감도와 출발성능을 주관적인 느낌이 아닌 객관적인 데이터로 표현할 수 있는 연구를 수행할 예정이다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.034

kci_detailed_000118.xml

ART001822566

oai_dc

압축성유체 유량계측장치 설계 및 제작

Design and Building of Flow-rate Measurement Apparatus for Compressible Fluid

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "지상원(부경대학교); 장지성(부경대학교)" ]

공기압 구동시스템에서 밸브를 통과하는 압축공기의 유량은 중요한 설계조건으로 정확한 계측이선결되어야 한다. 그러나 ISO 6358에서 제안된 유량계측법은 많은 시간과 에너지가 소비되는 작업이며 계측정확도 확보도 용이하지 않다. 따라서, 본 연구에서는 등온용기를 이용하여 각종 밸브 및실린더, 피팅, 전달관로 등과 같은 공기압 부품의통과유량 및 누설유량을 계측 할 수 있는 계측장치를 설계하였다. 설계된 계측장치는 최대6.343[dm3/(s·bar)]의 음속컨덕턴스를 계측 할 수있도록 설계하여 제작하였다. 제작된 계측장치의 등온성능 확인을 위하여 최대유량을 인가하여 용기내부 온도변화를 계측한 결과, 용기내부 온도변화량이 4[K]미만으로 억제되고 있음을 확인하였다. 또한, 계측장치의 유량방출 경로상에부착된 밸브와 피팅 및 관로 등에 의해 본 계측장비의 임계압력비는 0.35로 나타났고, 음속컨덕턴스는7.320 [dm3/(s·bar)]로 나타났으므로, 본 계측장비로설계목표치인 최대 음속컨덕턴스 6.343[dm3/(s·bar) ] 을 계측 할 수 있음을 확인하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.029

kci_detailed_000118.xml

ART001822550

oai_dc

연비 평가를 위한 6속 DCT기반 HEV 성능 시뮬레이터의 개발

Development of Performance Simulator for 6-speed DCT-based Hybrid Electric Vehicle to Evaluate the Fuel Economy

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "백진주(성균관대학교); 이용관(성균관대학교); 박진현(성균관대학교); 한관수(성균관대학교); 황성호(성균관대학교)" ]

6속 DCT기반 디젤 HEV 모델링을 구현하였으며, 동일한 디젤 HEV에 변속기를 AT와 DCT로 변경하여 FTP75와 NYCC 주행모드에 따른 SOC 및 연비 결과를 비교하였다. 이를 통해 얻어진 결론은 다음과같다. - 6속 DCT기반 HEV 성능 시뮬레이터를 개발하였으며, FTP75와 NYCC 주행모드를 통해 시뮬레이션 결과를 확인하였다. - 디젤 HEV에 변속기로 AT와 DCT를 각각 장착한 차량 모델링을 수행하였으며, 시뮬레이션을 통해얻어진 SOC 변화량과 연비를 비교하였다. - AT기반 디젤 HEV의 경우, 토크 컨버터로 인한동력손실로 인해 DCT기반 디젤 HEV의 SOC 및 연비 효율이 약 12% 정도 향상됨을 확인하였다. - 현재 AT모델은 락업(lockup) 상태를 고려하지않았으며, 이를 고려한 AT 모델로 보완하여 비교한다면 연비효율 향상 정도가 현재의 결과보다는 다소감소될 것으로 예측된다. 향후, AT 모델링 보완과 DCT 모델에 클러치 액추에이터 모델을 추가함으로써 액추에이터 제어에따른 클러치 제어 성능을 확인할 예정이다. 이를 통해 본 성능 시뮬레이터는 6속 DCT기반 HEV의 최적화된 연비 및 동력 성능 알고리즘 개발에 효과적으로 활용될 수 있을 것이다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.001

kci_detailed_000118.xml

ART001822555

oai_dc

선진사 트랙터 자동변속기 설계 분석

Automatic Transmission Design Analysis of the Tractor from Advanced Company

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교)" ]

본 연구에서는 100마력급 이상 트랙터에 적용되는Kuboda와 John Deere사의 24단 자동변속기를 대상으로 정비 매뉴얼에서 제공되는 자료를 토대로 기어열, 유압제어시스템, 변속제어기의 설계를 분석하였다. 향후에는 TCU 성능분석기를 개발하고 이를 활용하여 실차시험을 통해서 보다 상세한 작동 및 제어성능을 분석한 후 독자모델 자동변속기 개발에 반영할 예정이다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.4.007

kci_detailed_000118.xml

ART001748011

oai_dc

사판식 유압 피스톤 펌프의 슬리퍼 정압베어링면 형상에 관한 이론해석

Theoretical Analysis of the Slipper Hydrostatic Bearing Shape in the Swash Plate Type Axial Piston Pump

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조인성(전북대학교)" ]

이상과 같이 사판식 유압 피스톤 펌프의 슬리퍼 정압베어링 형상에 따른 이론해석을 통해 다음과 같은결론을 얻었다. 1) 슬리퍼의 랜드 부분과 환상 포켓부의 압력분포와 부하용량은 슬리퍼 형상에 의존하며, 모델 A가 가장 크게 나타났으며, 압력분포에 의해 계산된 부하용량은 모델 A가 가장 크게 나타났다. 2) 슬리퍼의 형상에 따라 누설유량, 유막두께 및동력손실 등이 좌우됨을 확인할 수 있었으며, 유막두께가 6 미만의 경우에는 모델 C가, 그 이상의 유막두께를 갖는 구간에서는 모델 B가 동력손실이 가장 작음을 확인하였다. 3) 점도와 유막두께의 변화에 따른 누설과 부하용량 측면에서는 모델 A가 누설은 적고, 부하용량은 크게 나와 가장 우수함을 확인할 수 있었다. 따라서 슬리퍼의 형상에 따라 윤활과 성능특성이결정됨을 확인할 수 있었고, 사용조건 및 요구조건에따른 최적의 성능을 얻을 수 있는 슬리퍼의 형상을설계하기 위한 기초 자료로 활용할 수 있을 것으로여겨진다.

기계공학

null

kci_detailed_000118.xml

ART001748023

oai_dc

A Study of Wind Energy Conversion System by a Secondary Control Hydrostatic Transmission

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "안경관(울산대학교); 도황팅(울산대학교)" ]

Wind energy has been more and more important and contributive in the energy utilization of the world. This paper proposed a novel method for Wind Energy Conversion System (WECS), in which a secondary control hydrostatic transmission (SC-HST) with two hydraulic accumulators, were employed for wind energy conversion system. This approach can absorb the excessive power of turbine, keep the generator from over-speed and maintain the speed of generator in low speed of turbine. A PID controller was designed for speed control to track a predefined speed. The simulation results indicated that the speed of the generator was ensured with the relative error less than 2%; and the efficiency of the proposed system was 70.4%.

기계공학

null

kci_detailed_000118.xml

ART001747995

oai_dc

마찰력 보상을 고려한 공기압 실린더의 위치제어

Position Control of a Pneumatic Cylinder Considering Friction

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김도태(경일대학교); 장중걸(경일대학교)" ]

본 연구에서는 마찰력을 고려한 공기압 실린더의위치제어 성능을 향상시키기 위해, H∞ 제어와 임펄스 제어를 수행한 결과, 다음과 같은 결론을 얻었다. (1) 공기압 실린더의 정마찰과 동마찰을 추정할 수있는 마찰력 관측기를 설계하고, 그 유효성을 검토하였다. (2) 공기압 실린더 위치제어계에 H∞ 제어와 임펄스제어를 동시에 수행한 결과, 과도응답 특성은 큰차이가 없지만 정상상태 오차를 줄이는 데 임펄스제어가 효과적인 것을 확인하였다.

기계공학

null

kci_detailed_000118.xml

ART001748004

oai_dc

대유량 솔레노이드 밸브 개발에 관한 연구

A Study on Development of High Flow Solenoid Valves

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정찬세(울산대학교); 양순용(울산대학교)" ]

본 연구는 대유량 솔레노이드 밸브 개발을 위한 연구를 수행하였고 다음과 같은 결론을 구하였다. 1) 대유량 솔레노이드 밸브의 작동원리 및 기초이론을 정립하였다. 2) AMESim을 이용하여 대유량 밸브를 모델링하였으며 시뮬레이션 결과를 통하여 밸브의 각 파라미터에 따른 밸브의 거동을 확인 하였다. 3) 대유량 솔레노이드 밸브의 상부 및 하부 다이아프램 오리피스 직경에 따른 밸브의 거동을 검증하였다. 4) 기초 이론 및 시뮬레이션을 기반으로 대유량 솔레노이드 밸브를 설계하고 제작하였다. 5) 공압 솔레노이드 밸브의 성능 시험을 위한 시험장치를 설계 및 제작하였다. 6) 제작된 성능시험기를 통한 실험으로 개발된 제품의 특성 및 성능을 시험하였고 제품으로써의 가능성을 확인하였다.

기계공학

null

kci_detailed_000118.xml

ART001748038

oai_dc

Development of a Virtual Excavator using SimMechanics and SimHydraulic

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "레광환(울산대학교); 정영만(울산대학교); 웬치탄(울산대학교); 양순용(울산대학교)" ]

Excavation is an important work in mining, earth removal and general earthworks. Nowadays, automation in excavator has been studied by several researchers. In the excavator research methods, simulation is one of the low cost methods for applied to test safely. In this paper, designed a virtual hydraulic excavator that with the control and the dynamic. At first, the simulation of hydraulic system for excavator’s attachment such as boom, arm and bucket using Matlab/Simhydraulic is presented. Second, the dynamic model of excavator is distributed to combine with the hydraulic system. For controlling this system, electric joysticks are used to operate the orifice open areas in Main Control Valve. The simulation result is described to analysis the performance of this virtual excavator.

기계공학

null

kci_detailed_000118.xml

ART001798157

oai_dc

유압 베인 펌프에서의 탄성유체윤활 해석

Elastohydrodynamic Lubrication Analysis in Hydraulic Vane Pump

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "박태조(경상대학교)" ]

본 논문에서는 유한차분법과 뉴우튼-랍슨 방법을사용하여 유압 베인 펌프의 베인과 캠링 사이에서 발생하는 접촉길이가 유한한 선접촉 EHL 문제를 처음으로 수치해석하였다. 이때, 베인 폭방향으로의 유압유 누설은 제한하였다. 이 결과, 최대 유체압력과 최소유막두께는 항상 베인의 접촉폭 양단부에서 발생하였다. 또한, 동일한 운전조건에 대하여 로울러 베어링의 경우보다 발생압력은 낮고 유막두께는 크게 되므로 윤활상태는 상대적으로 양호할 것으로 예측되었다. 본 논문의 수치해석 방법과 결과는 베인 펌프의베인과 캠링의 설계 및 성능향상에 유용하게 사용될수 있을 것으로 기대된다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.3.007

kci_detailed_000118.xml

ART001798155

oai_dc

브레이크 압력 추정을 적용한 구동력 제어

Traction Control with Brake Pressure Estimation

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김세윤(강릉원주대학교)" ]

브레이크 압력의 추정을 통해 브레이크 압력을 제어할 수 있는 알고리즘을 구성하였고 차량 구동력 제어에 이를 접목시켜 차량 적용성을 고찰하여 얻은 결과는 다음과 같다. 1) 솔레노이드 밸브의 구동신호와 작동시간을 이용하여 브레이크 압력을 추정하는 방법을 제안하였고브레이크 압력 형성 실험을 통해 얻은 결과로부터추정 방법의 타당성을 확인하였다. 2) 차량 구동력 제어의 시뮬레이션 결과로부터 브레이크 압력을 제어 변수로 정하여 직접 제어할 수있는 가능성을 확인하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.9.3.001

kci_detailed_000118.xml

ART001798167

oai_dc

다이어프램형 밸브의 유량특성과 동적성능에 관한 연구

A Study on Flow Rate Characteristic and Dynamic Performance on Diaphragm Solenoid Valve

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정찬세(울산대학교); 양순용(울산대학교)" ]

본 연구는 다이어프램 밸브의 유량특성과 동적성능에 대하여 연구를 수행하였고 다음과 같은 결론을도출하였다. 1) 다이어프램 밸브의 작동원리 및 기초이론을 정립하였고 밸브의 성능에 영향을 미치는 파라미터를정리하였다. 2) AMESim을 이용하여 다이어프램 밸브를 모델링하였으며 시뮬레이션 결과를 통하여 밸브의 다이어프램 오리피스 면적에 따른 밸브의 거동을 확인 하였다. 3) 다이어프램 밸브의 오리피스 직경에 따른 밸브의 거동을 실험을 통하여 검증하였다. 4) 다이어프램 오리피스 면적이 작을수록 유효단면적이 넓은 것을 확인하였다. 5) 다이어프램 오리피스 면적에 따른 밸브의 동적성능은 큰 차이가 나지 않는 것을 확인하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.3.027

kci_detailed_000118.xml

ART001798163

oai_dc

유압실린더-토글 서보 메카니즘의 모델링 및 운동제어

Modeling and Motion Control for Hydraulic Cylinder-Toggle Servomechanism

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조승호(홍익대학교)" ]

본 연구에서는 토글 메카니즘을 MBS기법으로 3D CAD모델링 한 후, AC서보모터-정용량형 기어펌프를 사용하는 유압실린더와 인터페이스 시켜 버추얼디자인 모델을 구축하였다. 고성능의 서보응답과 고 에너지 효율의 결합은 오늘날 사출성형기에 있어서는 필수불가결하다. 사출성형 공정에서 클램프 실린더는 다양한 작동 조건하에서 작업이 수행되도록 요구된다. 따라서 강인한 추적 제어 성능이 요구되므로 PID제어와 슬라이딩 모드를결합하는 방식을 도입하였다. 토글 메카니즘의 크로스헤드와 가동형판의 속도, 변위응답 특성을 고찰하기 위하여, 개회로 시뮬레이션을 수행하였다. 이로부터 전달함수의 설계 파라미터 값을 추출하여 제어기설계에 이용하였다. 슬라이딩모드를 결합에 의하여 응답속도를 빠르게하는 효과가 현저하여, 그 결과 가동형판의 응답성이향상되고 아울러 형체력이 빠르게 형성되므로 DCT 의 단축도 가능하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.3.021

kci_detailed_000119.xml

ART001798161

oai_dc

피드백 선형화 보상기와 외란 관측기를 이용한 2개 유압 실린더의 동기 제어

Synchronization Control of Two Hydraulic Cylinders Using Feedback Linearization Compensator and Disturbance Observer

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "감주성(부경대학교); 오동훈(부경대학교); 이일영(부경대학교); 김지웅(SG 서보 (주)); 이현철(SG 서보 (주))" ]

본 논문에서는 2개의 유압 실린더 위치를 동기제어하기 위한 제어 알고리즘을 제안하였다. 제안한 알고리즘은 각각의 실린더 위치를 제어하기 위한 부분과동기제어를 위한 부분으로 구성된다. 각각의 실린더위치를 제어하기 위한 알고리즘으로는 피드백 선형화보상기와 외란 보상기가 적용되었으며, 동기화 제어보상기로는 교차형 오차 판별기와 PI제어기가 사용되었다. 제안한 제어 알고리즘을 적용한 2축 유압 실린더동기제어 시스템의 제어 성능을 시뮬레이션을 통하여 조사하였으며, 서로 다른 크기의 외란이 작용하는 2 개 실린더의 위치를 신속하고 정밀하게 제어할 수 있음을 확인하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.3.014

kci_detailed_000119.xml

ART001772782

oai_dc

스마트폰 앱을 이용한 산업용 엔진의 모니터링 시스템 개발에 관한 연구

A Study on Development of Industrial Engine Monitoring System Using Smart Phone Application

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정찬세(울산대학교); 김용석(울산대학교); 정영만(울산대학교); 고주현(울산대학교); 정광식(명품기업); 이효성(명품기업); 양순용(울산대학교)" ]

본 연구에서는 산업용 중형엔진의 시운전환경개선을 위하여 ISM Band의 통신을 통해 엔진의 시운전데이터를 모니터링 하는 유·무선 통신시스템을 설계하고 제작하다. 또한 스마트폰 어플리케이션을 이용한 모니터링 시스템을 개발하고 테스벤치를 구축하였으며, 다음과 같은 결과를 도출하였다. 1) 데이터 획득시스템(DAQS)인 RTU(Remote Terminal Unit)와 게이트웨이인 MCU (Master Control Unit)를 개발하였다. 2) Zigbee 통신을 이용한 무선 통신 모니터링 시스템을 구축하였다. 3) PC 기반의 GUI 프로그램을 개발하고 유무선 통신 테스트벤치를 구축하였다. 4) WiFi 통신과 스마트폰 어플리케이션을 이용한실시간 모니터링시스템을 개발하였다. 5) 기 개발된 시스템의 테스트벤치를 통한 검정시험을 수행하여 산업용 엔진 운전데이터의 모니터링시스템으로 적용 가능성을 확인하였다

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.2.007

kci_detailed_000119.xml

ART001772773

oai_dc

에어스프링 시스템의 성능 개선에 관한 연구

A Study on the Performance Improvement of an Air Spring System

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "장지성(부경대학교)" ]

This study describes a method which can attenuate reaction force effectively for an air spring system composed of an air spring and auxiliary chamber. For the analysis, the nonlinear governing equation of the air spring system is derived. For a performance improvement of the system, change of the heat transfer effect and the mass flow rates is included in the analysis of the air spring system. The simulation study is presented to show the reaction force is changed by variations in heat transfer characteristics and the air spring system of isothermal process has the best performance. As a result, to improve attenuation characteristics of reaction force, a process in the air spring system should be maintained near isothermal process.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.2.001

kci_detailed_000119.xml

ART001772803

oai_dc

강제배기를 이용한 굴삭기 공기조화 시스템에 관한 연구

A Study on Air-Conditioning System for Excavator using Forced Exhaust

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "황지현(울산대학교); 정찬세(울산대학교); 고주현(울산대학교); 양순용(울산대학교)" ]

본 연구에서는 강제배기를 이용한 굴삭기 캐빈의공기조화 시스템에 대한 연구를 수행하여 다음과 같은 결론을 도출하였다. 1) 강제배기를 이용한 굴삭기 캐빈 공기조화 시스템의 원리와 기초이론을 정립하였다. 2) AMESim을 이용하여 강제배기를 이용한 공기조화 시스템의 모델을 개발하였으며 흡입공기온도와배기유량에 따른 캐빈 내부 온도변화를 확인하였다. 3) AMESim 시뮬레이션을 통하여 흡입공기온도가낮고 배기유량이 많을수록 캐빈 내부 온도가 급격히낮아지는 것을 확인하였다. 4) 실내실험을 통하여 자연대류를 이용한 캐빈 온도변화와 강제대류를 이용한 캐빈 온도변화를 비교하였으며 52℃에서 30℃까지 낮아지는 시간은 강제대류가 약 250s 빨리 낮아지는 것을 확인하였다. 5) 실외실험을 통하여 실제 일사량이 적용된 동안캐빈의 내부온도를 측정하였으며 배기유량을 변경하고 태양열을 받는 면적을 변경하여 강제배기 시스템의 적용 가능성을 검증하였다. 본 연구에서는 강제배기 시스템의 적용 가능성을검증하기 위하여 개방형 캐빈을 자체적으로 밀폐형으로 변경하여 시스템을 구성, 실험하였다. 따라서 실제밀폐형 캐빈 보다 열악한 환경에서 시험을 수행하여실제 사용 환경에서의 성능은 실험에서 얻어진 결과보다 향상되리라 예상 된다 . 향후 각 굴삭기 캐빈의형태나 부피에 따른 시스템의 최적화를 위한 연구가진행되어야 할 것으로 판단된다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.2.023

kci_detailed_000119.xml

ART001772805

oai_dc

트랙터 8단 자동변속기 기어 열 설계

Gear Train Design of 8-Speed Automatic Transmission for Tractor

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "정규홍(대진대학교)" ]

트랙터는 다양한 부속작업기를 이용하여 농업, 축산업뿐만 아니라 소형 건설기계로도 활용되고 있으며빈번한 변속조작이 수반되는 작업의 효율성을 높이고운전자의 편의성 향상을 위하여 자동변속기능이 요구되고 있다. 본 연구에서는 국산화 개발이 시도되고 있는 100마력급 트랙터 자동변속기에 적용되는 8단 주 변속 기어열을 3축과 2축을 갖는 2가지 방식으로 설계하였으며속도분석을 통해 동력전달체계와 변속특성을 고찰하였다. 또한 동력전달경로에 대한 기구학적 분석을 통해 각 변속단에서의 변속비가 주어졌을 때 이를 구현할 수 있는 기어비를 계산하는 방법을 제시하였다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.2.030

kci_detailed_000119.xml

ART001772791

oai_dc

에너지보존과 토크평형을 이용한 제로터 유압 펌프/모터의 배제용적 해석 - 내․외부로터 회전 경우 -

An Analysis on Volumetric Displacement of Hydraulic Gerotor Pump/Motor using Energy and Torque Equilibrium - First Report: Case of Rotation of Inner and outer Rotors -

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김성동(금오공과대학교); 김대명((주)대화산기); 함영복(한국기계연구원)" ]

본 연구의 주요 결론은 다음과 같이 요약된다. 1) 제로터 기구에서 내․외부로터의 중심과 피치점이 일정하게 주어진 상태에서 내․외부로터 의 로우브 수에 반비례하는 속도로 회전하는 운동형태의경우에 대하여 모터에 공급되는 유압에너지와 모터측의 기계적 에너지 사이의 에너지 보존원리와 로터에대한 토크평형을 이용하여 모터용적을 산출하는 방법을 제시하였다. 2) 유압에너지와 모터측의 기계적 에너지 사이의에너지 보존원리와 로터에 대한 토크평형을 이용하여모터용적을 산출하는 결과공식이 회전날개길이법의 배제용적 결과 수식이 동일함을 이론적으로 증명하였다. 3) 또 다른 검증방법으로서 접촉점 사이의 챔버용적을 이용하여 산출된 배제용적 결과와 수치해석적인 방법으로 비교하였으며, 에너지 보존원리와 로터에 대한 토크평형을 이용한 모터용적과 유량에 관한이론과 수식의 타당성을 확인하였다. 4) 에너지보존과 토크평형을 이용하여 유량과 배제용적을 산출하는 방법의 계산과정이 단순히 내외부로터의 접촉점의 좌표만을 이용하기 때문에 복잡한형상의 내․외부로터사이 챔버용적을 구하는 방법보다 간단하다. 5) 에너지보존과 토크평형 이용법이 회전날개길이법과 계산과정의 난이도가 유사하지만, 축의 구동 토크와 배제용적의 상관관계를 직접적으로 보여주기 때문에 토크사양이 주어진 유압모터의 설계에 이용이효율적일 것이다.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2013.10.2.013

kci_detailed_000119.xml

ART001690642

oai_dc

항공기의 도어 댐퍼용 교축 오리피스의 설계

Design of Throttle Orifices for an Aircraft Door Damper

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "권용철(한국항공대학교); 김종혁(한국항공대학교); 홍예선(한국항공대학교); 김상범(한화)" ]

In this study the flow rate-to-pressure difference characteristics of short-tube type damping orifices for an aircraft door damper were investigated by CFD analyses and experiments. As the design parameters of the damping orifice its diameter, inlet and outlet angle, tube length and the viscosity of the working fluid were taken into consideration. The results showed that the discharge coefficient of the orifices are dependant on the inlet and outlet angle and the oil viscosity, while their length plays an little significant role. Although the short-tube type damping orifice was employed to induce a turbulent flow, their discharge coefficient decreases rapidly as the oil viscosity gets higher than 50mm2/s. Therefore, in order to determine the orifice size,satisfying the working temperature range of the door damper, the oil viscosity as well as the friction force on the damper piston should be kept within proper values. For the verification of the CFD analysis results the actual performance of a door damper was measured and compared with them.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2012.9.3.023

kci_detailed_000119.xml

ART001690579

oai_dc

사출성형 실린더의 적응제어 방식 속도 및 압력제

Adaptive Control Based Velocity and Pressure Control for Injection Molding Cylinder

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "조승호(홍익대학교)" ]

This paper deals with the issue of model reference adaptive control strategy to control the injection molding machine. Prior to controller design, a pair of transfer functions are derived for the injection and dwelling process based on mathematical models of components. As external disturbances to examine the robustness of the proposed controller, nozzle clogging and contraction of molded objects are considered and realized by proportional valve. The overall simulation system, consisting of hydraulic components, controller and sensors, is implemented using the components of commercial software SimulationX. The simulation results confirm the proposed scheme's efficiency and robustness.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2012.9.3.001

kci_detailed_000119.xml

ART001690583

oai_dc

피드백 선형화 제어기를 사용한 1/4 차량 현가장치 시뮬레이터의 위치 제어

Position Control of a 1/4 Car Suspension Simulator using a Feedback Linearization Controller

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "김태형(대한항공); 이일영(부경대학교)" ]

In the study, a control strategy using a feedback linearization compensator and a disturbance observer was suggested and applied to a hydraulic control system for a vehicle suspension simulator. Although the hydraulic system has comparatively big external loads composed by constant and varying loads, it is ascertained that excellent control performances are obtained with the suggested control strategy.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2012.9.3.008

kci_detailed_000119.xml

ART001690646

oai_dc

콤플렉스법에 의한 롤러-링크 부착형 전도수문 구동용 유압실린더의 최적 설치점 설계

Design of Optimal Locating Point of the Hydraulic Cylinder Actuating a Roller-Link Type Rotating Floodgate

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "이성래(건양대학교)" ]

The hydraulic cylinder is used for actuating the roller-link type rotating floodgate which controls the volume of water in the reservoir. The locating points of hydraulic cylinder are restricted to the limited space and determined to minimize the cylinder force necessary for actuating the floodgate. Generally, the head end point of cylinder is fixed at underground and the rod end point of cylinder is connected to the support link. Therefore there exist three design variables to be determined to minimize the cylinder force within the rotating range of floodgate. First, the mathematical model of the roller-link type rotating floodgate is derived to find the cylinder force corresponding to the floodgate angle. Then, the optimal locating point of hydraulic cylinder is searched using the complex method that is one kind of constrained direct search method.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2012.9.3.029

kci_detailed_000119.xml

ART001690620

oai_dc

Position control of Electro hydrostatic actuator (EHA) using a modified back stepping controller

{ "journal_name": "사단법인 유공압건설기계학회", "publisher": null, "pub_year": null, "pub_month": null, "volume": null, "issue": null }

[ "도안녹치남(울산대학교); 윤종일(울산대학교); 안경관(울산대학교)" ]

Nowadays, electro hydrostatic actuator (EHA) has shown great advantages over the conventional hydraulic actuators with valve control system. This paper presents a position control for an EHA using a modified back stepping controller. The controller is designed by combining a backstepping technique and adaptation laws via special Lyapunov functions. The control signal consists of an adaptive control signal to compensate for the nonlinearities and a simple robust structure to deal with a bounded disturbance. Experiments are carried out to investigate the effectiveness of the proposed controller.

기계공학

null

http://dx.doi.org/10.7839/ksfc.2012.9.3.016

kci_detailed_000119.xml