meshcat-viewer-dae.py

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# This examples shows how to load and move a robot in meshcat.
# Note: this feature requires Meshcat to be installed, this can be done using
# pip install --user meshcat

import pinocchio as pin
import numpy as np
import sys
import os
from os.path import dirname, join, abspath

from pinocchio.visualize import MeshcatVisualizer

# Load the URDF model.
# Conversion with str seems to be necessary when executing this file with ipython
pinocchio_model_dir = join(dirname(dirname(str(abspath(__file__)))),"models")

model_path = join(pinocchio_model_dir,"example-robot-data/robots")
mesh_dir = pinocchio_model_dir
urdf_filename = "romeo_small.urdf"
urdf_model_path = join(join(model_path,"romeo_description/urdf"),urdf_filename)

model, collision_model, visual_model = pin.buildModelsFromUrdf(urdf_model_path, mesh_dir, pin.JointModelFreeFlyer())

# Currently, MeshCat is not able to retrieve the scaling from DAE files. Set it manually.
for geom in visual_model.geometryObjects:
  s = geom.meshScale 
  s *= 0.01
  geom.meshScale = s

viz = MeshcatVisualizer(model, collision_model, visual_model)

# Start a new MeshCat server and client.
# Note: the server can also be started separately using the "meshcat-server" command in a terminal:
# this enables the server to remain active after the current script ends.
#
# Option open=True pens the visualizer.
# Note: the visualizer can also be opened seperately by visiting the provided URL.
try:
    viz.initViewer(open=True)
except ImportError as err:
    print("Error while initializing the viewer. It seems you should install Python meshcat")
    print(err)
    sys.exit(0)

# Load the robot in the viewer.
# Color is needed here because the Romeo URDF doesn't contain any color, so the default color results in an
# invisible robot (alpha value set to 0).
viz.loadViewerModel(color = [0.0, 0.0, 0.0, 1.0])

# Display a robot configuration.
q0 = np.array([
    0, 0, 0.840252, 0, 0, 0, 1,  # Free flyer
    0, 0, -0.3490658, 0.6981317, -0.3490658, 0,  # left leg
    0, 0, -0.3490658, 0.6981317, -0.3490658, 0,  # right leg
    0,  # chest
    1.5, 0.6, -0.5, -1.05, -0.4, -0.3, -0.2,  # left arm
    0, 0, 0, 0,  # head
    1.5, -0.6, 0.5, 1.05, -0.4, -0.3, -0.2,  # right arm
]).T
viz.display(q0)

# Display another robot.
red_robot_viz = MeshcatVisualizer(model, collision_model, visual_model)
red_robot_viz.initViewer(viz.viewer)
red_robot_viz.loadViewerModel(rootNodeName = "red_robot", color = [1.0, 0.0, 0.0, 0.5])
q = q0.copy()
q[1] = 1.0
red_robot_viz.display(q)