File size: 5,123 Bytes
985c397 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 | # (c) 2014 David Douard <david.douard@gmail.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License (LGPL)
# as published by the Free Software Foundation; either version 2 of
# the License, or (at your option) any later version.
# for detail see the LICENCE text file.
#
# FCGear is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public
# License along with FCGear; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
import itertools
from involute import CreateExternalGear, CreateInternalGear, rotate
class SVGWireBuilder(object):
def __init__(self):
self.theta = 0.0
self.pos = None
self.svg = []
def move(self, p):
p = rotate(p, self.theta)
self.svg.append("M %s,%s" % (p[0], p[1]))
self.pos = p
def line(self, p):
p = rotate(p, self.theta)
self.svg.append("L %s,%s" % (p[0], p[1]))
self.pos = p
def arc(self, p, r, sweep):
p = rotate(p, self.theta)
self.svg.append("A %s,%s 0,0,%s %s,%s" % (r, r, str(sweep), p[0], p[1]))
self.pos = p
def curve(self, *points):
"""Add a Bezier curve from self.pos to points[-1]
every other points are the control points of the Bezier curve (which
will thus be of degree len(points) )
"""
assert len(points) == 3
points = [rotate(p, self.theta) for p in points]
self.svg.append("C %s,%s %s,%s %s,%s" % tuple(itertools.chain(*points)))
self.pos = points[-1]
def close(self):
self.svg.append("Z")
if __name__ == "__main__":
from optparse import OptionParser
p = OptionParser(
usage="usage: %prog [options] [[MODULE] NUMER_OF_TEETH]",
description=(
"Generates the outline of a metric, involute gear. "
"Prints out an SVG path. "
"This is mainly a debugging tool to quickly inspect the gear visually. "
"For this, online tools like https://yqnn.github.io/svg-path-editor/ are handy. "
"Most of the time it's enough to just use the first 20 lines or so, e.g.:\n\t"
"%prog -z50 | head -n20 | pbcopy"
),
)
p.add_option(
"-z",
"--numer-of-teeth",
help="The number of teeth for the gear.",
metavar="NUMER_OF_TEETH",
type="int",
)
p.add_option(
"-m",
"--module",
help="The metric module, in svg user unit, i.e. unit-less. [default: %default]",
metavar="MODULE",
type="float",
default=1,
)
p.add_option(
"-p",
"--pressure-angle",
help="The pressure angle, in degree. [default: %default]",
metavar="PRESSURE_ANGLE",
type="float",
default=20,
)
p.add_option(
"-i",
"--internal",
help=(
"Generates an internal gear, i.e. the addednum points towards the center "
"and the root fillet is at the outside. [default: %default]"
),
action="store_true",
default=False,
)
p.add_option(
"-a",
"--addendum",
help=(
"The tooth height above the pitch line, normalized by the MODULE. "
"[default: %default]"
),
metavar="ADDENDUM_COEFFICIENT",
type="float",
default=1,
)
p.add_option(
"-d",
"--dedendum",
help=(
"The tooth height from the root to the pitch line, normalized by the MODULE. "
"[default: %default]"
),
metavar="DEDENDUM_COEFFICIENT",
type="float",
default=1.25,
)
p.add_option(
"-f",
"--fillet-radius",
help=("The radius of the root fillet, normalized by the MODULE. " "[default: %default]"),
metavar="FILLET_RADIUS_COEFFICIENT",
type="float",
default=0.38,
)
opts, args = p.parse_args()
errors = []
if len(args) == 1:
opts.numer_of_teeth = int(args[0])
if len(args) == 2:
opts.module = float(args[0])
opts.numer_of_teeth = int(args[1])
if len(args) > 2:
errors.append("Too many arguments.")
if opts.numer_of_teeth is None:
errors.append("No number of teeth given.")
if len(errors) > 0:
errors.append("Try --help for more info.")
p.error("\n".join(errors))
w = SVGWireBuilder()
generator_func = CreateInternalGear if opts.internal else CreateExternalGear
generator_func(
w,
opts.module,
opts.numer_of_teeth,
opts.pressure_angle,
addCoeff=opts.addendum,
dedCoeff=opts.dedendum,
filletCoeff=opts.fillet_radius,
)
for l in w.svg:
print(l)
|