python/examples/transforms.py

"""
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and proprietary rights in and to this software, related documentation
and any modifications thereto. Any use, reproduction, disclosure or
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license agreement from NVIDIA CORPORATION is strictly prohibited.


Visualize Transforms
--------------------
Compute and visualize relative transforms for different locations on a cabinet
- Compute transforms on different rigid bodies on cabinet with offsets
- Visualize transforms using wireframe axes/sphere
"""

import os
import math
from isaacgym import gymapi
from isaacgym import gymutil

# Initialize gym
gym = gymapi.acquire_gym()

# Parse arguments
args = gymutil.parse_arguments(description="Visualize Transforms")

# configure sim
sim_params = gymapi.SimParams()
sim_params.gravity = gymapi.Vec3(0.0, -9.8, 0.0)
sim_params.dt = 1.0 / 60.0
sim_params.substeps = 2
if args.physics_engine == gymapi.SIM_FLEX:
    sim_params.flex.solver_type = 5
    sim_params.flex.num_outer_iterations = 4
    sim_params.flex.num_inner_iterations = 15
    sim_params.flex.relaxation = 0.75
    sim_params.flex.warm_start = 0.5
elif args.physics_engine == gymapi.SIM_PHYSX:
    sim_params.physx.solver_type = 1
    sim_params.physx.num_position_iterations = 4
    sim_params.physx.num_velocity_iterations = 1
    sim_params.physx.num_threads = args.num_threads
    sim_params.physx.use_gpu = args.use_gpu

sim_params.use_gpu_pipeline = False
if args.use_gpu_pipeline:
    print("WARNING: Forcing CPU pipeline.")

sim = gym.create_sim(args.compute_device_id, args.graphics_device_id, args.physics_engine, sim_params)

if sim is None:
    print("*** Failed to create sim")
    quit()

# Add ground plane
plane_params = gymapi.PlaneParams()
gym.add_ground(sim, plane_params)

# Create viewer
viewer = gym.create_viewer(sim, gymapi.CameraProperties())
if viewer is None:
    print("*** Failed to create viewer")
    quit()

# Load asset relative to the current working directory
print("Working directory: %s" % os.getcwd())
asset_root = "../../assets"
asset_file = "urdf/sektion_cabinet_model/urdf/sektion_cabinet.urdf"
asset_options = gymapi.AssetOptions()
asset_options.armature = 0.01
# Fix the base link of the cabinet so it does not move
asset_options.fix_base_link = True
asset_options.use_mesh_materials = True
print("Loading asset '%s' from '%s'" % (asset_file, asset_root))
asset = gym.load_asset(sim, asset_root, asset_file, asset_options)

# Set up the environment grid with two environments
num_envs = 2
spacing = 1.0
env_lower = gymapi.Vec3(-spacing, 0.0, -spacing)
env_upper = gymapi.Vec3(spacing, spacing, spacing)


class Cabinet:

    DRAWER_GRASP = gymapi.Vec3(0.3, 0.0, 0.01)
    LEFT_DOOR_GRASP = gymapi.Vec3(0.03, 0.35, 0.185)
    RIGHT_DOOR_GRASP = gymapi.Vec3(0.03, -0.35, 0.185)

    TOP_DRAWER_INDEX = 8
    BOTTOM_DRAWER_INDEX = 6
    RIGHT_DOOR_INDEX = 4
    LEFT_DOOR_INDEX = 2

    def __init__(self, env, actor):
        self.env = env
        self.actor = actor

    def get_grasp_points(self):

        poses = gym.get_actor_rigid_body_states(self.env, self.actor, gymapi.STATE_POS)['pose']

        # Get pose for all of the handles
        top_drawer_handle_pose = gymapi.Transform.from_buffer(poses[self.TOP_DRAWER_INDEX])
        bottom_drawer_handle_pose = gymapi.Transform.from_buffer(poses[self.BOTTOM_DRAWER_INDEX])
        left_door_handle_pose = gymapi.Transform.from_buffer(poses[self.LEFT_DOOR_INDEX])
        right_door_handle_pose = gymapi.Transform.from_buffer(poses[self.RIGHT_DOOR_INDEX])

        # Offset drawer transforms to compute grasp locations
        top_drawer_point = top_drawer_handle_pose.transform_point(self.DRAWER_GRASP)
        bottom_drawer_point = bottom_drawer_handle_pose.transform_point(self.DRAWER_GRASP)
        left_door_handle_point = left_door_handle_pose.transform_point(self.LEFT_DOOR_GRASP)
        right_door_handle_point = right_door_handle_pose.transform_point(self.RIGHT_DOOR_GRASP)

        # Create transform from grasp location and handle rotation
        top_drawer_grasp = gymapi.Transform(top_drawer_point, top_drawer_handle_pose.r)
        bottom_drawer_grasp = gymapi.Transform(bottom_drawer_point, bottom_drawer_handle_pose.r)
        left_door_handle_grasp = gymapi.Transform(left_door_handle_point, left_door_handle_pose.r)
        right_door_handle_grasp = gymapi.Transform(right_door_handle_point, right_door_handle_pose.r)

        return top_drawer_grasp, bottom_drawer_grasp, left_door_handle_grasp, right_door_handle_grasp


cabinets = []

print("Creating %d environments" % num_envs)
for i in range(num_envs):
    # Create env
    env = gym.create_env(sim, env_lower, env_upper, 1)

    # Add cabinet model
    pose = gymapi.Transform()
    pose.p = gymapi.Vec3(0.0, 0.41, 0.0)
    pose.r = gymapi.Quat.from_euler_zyx(-0.5 * math.pi, 0, 0)
    ahandle = gym.create_actor(env, asset, pose, "cabinet", i, 1)

    # Cache rigid body handles in cabinet actor to refer to later
    cab = Cabinet(env, ahandle)
    dof_props = gym.get_actor_dof_properties(env, ahandle)

    # Set stiffness and damping of joint drives
    dof_props['stiffness'].fill(1000000.0)
    dof_props['damping'].fill(500.0)
    dof_props["driveMode"] = gymapi.DOF_MODE_POS
    gym.set_actor_dof_properties(env, ahandle, dof_props)
    cabinets.append(cab)

# Look at the first env
cam_pos = gymapi.Vec3(3, 1.5, 3)
cam_target = gymapi.Vec3(0, 0.5, 0)
gym.viewer_camera_look_at(viewer, None, cam_pos, cam_target)

# Create helper geometry used for visualization
# Create an wireframe axis
axes_geom = gymutil.AxesGeometry(0.1)
# Create a wireframe sphere
sphere_rot = gymapi.Quat.from_euler_zyx(0.5 * math.pi, 0, 0)
sphere_pose = gymapi.Transform(r=sphere_rot)
sphere_geom = gymutil.WireframeSphereGeometry(0.02, 12, 12, sphere_pose, color=(1, 1, 0))

while not gym.query_viewer_has_closed(viewer):

    # Step the physics
    gym.simulate(sim)
    gym.fetch_results(sim, True)

    gym.clear_lines(viewer)

    for i in range(num_envs):
        # Get cabinet from environment, each environment only has one cabinet
        cab = cabinets[i]

        # Get the transforms we want to visualize
        top_drawer_grasp, bottom_drawer_grasp, left_door_handle_grasp, right_door_handle_grasp = cab.get_grasp_points()

        # Top drawer
        gymutil.draw_lines(axes_geom, gym, viewer, cab.env, top_drawer_grasp)
        gymutil.draw_lines(sphere_geom, gym, viewer, cab.env, top_drawer_grasp)

        # Bottom drawer
        gymutil.draw_lines(axes_geom, gym, viewer, cab.env, bottom_drawer_grasp)
        gymutil.draw_lines(sphere_geom, gym, viewer, cab.env, bottom_drawer_grasp)

        # Left door
        gymutil.draw_lines(axes_geom, gym, viewer, cab.env, left_door_handle_grasp)
        gymutil.draw_lines(sphere_geom, gym, viewer, cab.env, left_door_handle_grasp)

        # Right door
        gymutil.draw_lines(axes_geom, gym, viewer, cab.env, right_door_handle_grasp)
        gymutil.draw_lines(sphere_geom, gym, viewer, cab.env, right_door_handle_grasp)

    # Update the viewer
    gym.step_graphics(sim)
    gym.draw_viewer(viewer, sim, True)

    # Wait for dt to elapse in real time.
    # This synchronizes the physics simulation with the rendering rate.
    gym.sync_frame_time(sim)

print("Exiting")
gym.destroy_viewer(viewer)
gym.destroy_sim(sim)