visualization problems，In ubuntu20.04, Using pycharm

[LHT-Liu]

ubuntu2024.04
Pycharm Community Edition 2024.1.1
pip install pin

I have a simple program that runs normally, but cannot be displayed visually on the web page. It is a blank meshcat page.

and my code is shown below

import sys
import pinocchio as pin
from pinocchio.visualize import MeshcatVisualizer
import numpy as np

urdf_path = "/home/lht/LHT/Python_Coppeliasim/fr3_with_hand.urdf"

model: pin.Model = pin.buildModelFromUrdf(urdf_path)
visual_model = pin.buildGeomFromUrdf(model, urdf_path, pin.GeometryType.VISUAL)
collision_model = pin.buildGeomFromUrdf(model, urdf_path, pin.GeometryType.COLLISION)

data: pin.Data = model.createData()

viz = MeshcatVisualizer(model, collision_model, visual_model)

try:
    viz.initViewer(open=True)
    # viz.loadViewerModel()
except ImportError as error:
    print(error)
    sys.exit(0)
viz.loadViewerModel()

q = pin.randomConfiguration(model)
q1 = pin.neutral(model)

viz.display(q)
viz.displayVisuals(True)

print("q=", q)
print("q1=", q1)

and my URDF code is shown below

<?xml version="1.0" ?>

<robot name="fr3">

   <link name="fr3_link0">
    <inertial>
      <origin xyz="-0.041018 -0.00014 0.049974" rpy="0 0 0" />
      <mass value="0.629769" />
      <inertia ixx="0.00315" ixy="8.2904E-07" ixz="0.00015" iyy="0.00388" iyz="8.2299E-06" izz="0.004285" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link0.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link0.stl"/>
      </geometry>
    </collision>
  </link>



  <link name="fr3_link1">
    <inertial>
      <origin xyz="0.003875 0.002081 -0.04762" rpy="0 0 0" />
      <mass value="4.970684" />
      <inertia ixx="0.70337" ixy="-0.000139" ixz="0.006772" iyy="0.70661" iyz="0.019169" izz="0.009117" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link1.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link1.stl"/>
      </geometry>
    </collision>
  </link>

  <joint name="fr3_joint1" type="revolute">
    <origin rpy="0 0 0" xyz="0 0 0.333"/>
    <parent link="fr3_link0"/>
    <child link="fr3_link1"/>
    <axis xyz="0 0 1"/>
    <limit effort="87.0" lower="-2.3093" upper="2.3093" velocity="2.0"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-2.3093" soft_upper_limit="2.3093"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link2">
    <inertial>
      <origin xyz="-0.003141 -0.02872 0.003495" rpy="0 0 0" />
      <mass value="0.646926" />
      <inertia ixx="0.007962" ixy="-0.003925" ixz="0.010254" iyy="0.02811" iyz="0.000704" izz="0.025995" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link2.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link2.stl"/>
      </geometry>
    </collision>
  </link>

  <joint name="fr3_joint2" type="revolute">
    <origin rpy="-1.5707963267948966 0 0" xyz="0 0 0"/>
    <parent link="fr3_link1"/>
    <child link="fr3_link2"/>
    <axis xyz="0 0 1"/>
    <limit effort="87.0" lower="-1.5133" upper="1.5133" velocity="1.0"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-1.5133" soft_upper_limit="1.5133"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link3">
    <inertial>
      <origin xyz="0.027518 0.039252 -0.066502" rpy="0 0 0" />
      <mass value="3.228604" />
      <inertia ixx="0.037242" ixy="-0.004761" ixz="-0.011396" iyy="0.036155" iyz="-0.012805" izz="0.01083" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link3.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link3.stl"/>
      </geometry>
    </collision>
  </link>

  <joint name="fr3_joint3" type="revolute">
    <origin rpy="1.5707963267948966 0 0" xyz="0 -0.316 0"/>
    <parent link="fr3_link2"/>
    <child link="fr3_link3"/>
    <axis xyz="0 0 1"/>
    <limit effort="87.0" lower="-2.4937" upper="2.4937" velocity="1.5"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-2.4937" soft_upper_limit="2.4937"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link4">
    <inertial>
      <origin xyz="-0.05317 0.104419 0.027454" rpy="0 0 0" />
      <mass value="3.587895" />
      <inertia ixx="0.025853" ixy="0.007796" ixz="-0.001332" iyy="0.019552" iyz="0.008641" izz="0.028323" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link4.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link4.stl"/>
      </geometry>
    </collision>
  </link>

  <joint name="fr3_joint4" type="revolute">
    <origin rpy="1.5707963267948966 0 0" xyz="0.0825 0 0"/>
    <parent link="fr3_link3"/>
    <child link="fr3_link4"/>
    <axis xyz="0 0 1"/>
    <!-- <limit effort="87.0" lower="-2.7478" upper="-0.4461" velocity="1.25"/> -->
    <limit effort="87.0" lower="-2.7478" upper="1" velocity="1.25"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-2.7478" soft_upper_limit="-0.4461"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link5">
    <inertial>
      <origin xyz="-0.011953 0.041065 -0.038437" rpy="0 0 0" />
      <mass value="1.225946" />
      <inertia ixx="0.035549" ixy="-0.002117" ixz="-0.004037" iyy="0.029474" iyz="0.000229" izz="0.008627" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link5.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link5.stl"/>
      </geometry>
    </collision>
  </link>
  
  <joint name="fr3_joint5" type="revolute">
    <origin rpy="-1.5707963267948966 0 0" xyz="-0.0825 0.384 0"/>
    <parent link="fr3_link4"/>
    <child link="fr3_link5"/>
    <axis xyz="0 0 1"/>
    <limit effort="12.0" lower="-2.48" upper="2.48" velocity="3.0"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-2.48" soft_upper_limit="2.48"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link6">
    <inertial>
      <origin xyz="0.060149 -0.014117 -0.010517" rpy="0 0 0" />
      <mass value="1.666555" />
      <inertia ixx="0.001964" ixy="0.000109" ixz="-0.001158" iyy="0.004354" iyz="0.000341" izz="0.005433" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link6.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link6.stl"/>
      </geometry>
    </collision>
  </link>
 
  <joint name="fr3_joint6" type="revolute">
    <origin rpy="1.5707963267948966 0 0" xyz="0 0 0"/>
    <parent link="fr3_link5"/>
    <child link="fr3_link6"/>
    <axis xyz="0 0 1"/>
    <!-- <limit effort="12.0" lower="0.8521" upper="4.2094" velocity="1.5"/> -->
    <limit effort="12.0" lower="-0.8521" upper="4.2094" velocity="1.5"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="0.8521" soft_upper_limit="4.2094"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link7">
    <inertial>
      <origin xyz="0.010517 -0.004252 0.061597" rpy="0 0 0" />
      <mass value="0.735522" />
      <inertia ixx="0.012516" ixy="-0.000428" ixz="-0.001196" iyy="0.010027" iyz="-0.000741" izz="0.004815" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/link7.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/link7.stl"/>
      </geometry>
    </collision>
  </link>
  
  <joint name="fr3_joint7" type="revolute">
    <origin rpy="1.5707963267948966 0 0" xyz="0.088 0 0"/>
    <parent link="fr3_link6"/>
    <child link="fr3_link7"/>
    <axis xyz="0 0 1"/>
    <limit effort="12.0" lower="-2.6895" upper="2.6895" velocity="3.0"/>
    <safety_controller k_position="100.0" k_velocity="40.0" soft_lower_limit="-2.6895" soft_upper_limit="2.6895"/>
    <dynamics D="1" K="7000" damping="0.003" friction="0.0" mu_coulomb="0" mu_viscous="16"/>
  </joint>



  <link name="fr3_link8"/>

  <joint name="fr3_joint8" type="fixed">
    <origin rpy="0 0 0" xyz="0 0 0.107"/>
    <parent link="fr3_link7"/>
    <child link="fr3_link8"/>
  </joint>



  <link name="fr3_hand">
    <inertial>
      <origin xyz="-0.01 0 0.03" rpy="0 0 0" />
      <mass value="0.73" />
      <inertia ixx="0.001" ixy="0" ixz="0" iyy="0.0025" iyz="0" izz="0.0017" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/hand.dae"/>
      </geometry>
    </visual>
    <collision>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/collision/hand.stl"/>
      </geometry>
    </collision>
  </link>

  <joint name="fr3_hand_joint" type="fixed">
    <parent link="fr3_link8"/>
    <child link="fr3_hand"/>
    <origin rpy="0 0 -0.7853981633974483" xyz="0 0 0"/>
  </joint>



  <!-- Define the hand_tcp frame -->
  <link name="fr3_hand_tcp"/>

  <joint name="fr3_hand_tcp_joint" type="fixed">
    <origin rpy="0 0 0" xyz="0 0 0.1034"/>
    <parent link="fr3_hand"/>
    <child link="fr3_hand_tcp"/>
  </joint>



  <link name="fr3_leftfinger">
    <inertial>
      <origin xyz="0 0 0" rpy="0 0 0" />
      <mass value="0.015" />
      <inertia ixx="0.0000023749" ixy="0" ixz="0" iyy="0.0000023749" iyz="0" izz="0.00000075" />
    </inertial>
    <visual>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/finger.dae"/>
      </geometry>
    </visual>
    <!-- screw mount -->
    <collision>
      <origin rpy="0 0 0" xyz="0 18.5e-3 11e-3"/>
      <geometry>
        <box size="22e-3 15e-3 20e-3"/>
      </geometry>
    </collision>
    <!-- cartriage sledge -->
    <collision>
      <origin rpy="0 0 0" xyz="0 6.8e-3 2.2e-3"/>
      <geometry>
        <box size="22e-3 8.8e-3 3.8e-3"/>
      </geometry>
    </collision>
    <!-- diagonal finger -->
    <collision>
      <origin rpy="0.5235987755982988 0 0" xyz="0 15.9e-3 28.35e-3"/>
      <geometry>
        <box size="17.5e-3 7e-3 23.5e-3"/>
      </geometry>
    </collision>
    <!-- rubber tip with which to grasp -->
    <collision>
      <origin rpy="0 0 0" xyz="0 7.58e-3 45.25e-3"/>
      <geometry>
        <box size="17.5e-3 15.2e-3 18.5e-3"/>
      </geometry>
    </collision>
  </link>



  <link name="fr3_rightfinger">
    <inertial>
      <origin xyz="0 0 0" rpy="0 0 0" />
      <mass value="0.015" />
      <inertia ixx="0.0000023749" ixy="0" ixz="0" iyy="0.0000023749" iyz="0" izz="0.00000075" />
    </inertial>
    <visual>
      <origin rpy="0 0 3.141592653589793" xyz="0 0 0"/>
      <geometry>
        <mesh filename="/home/lht/LHT/Python_Coppeliasim/meshes/visual/finger.dae"/>
      </geometry>
    </visual>
    <!-- screw mount -->
    <collision>
      <origin rpy="0 0 0" xyz="0 -18.5e-3 11e-3"/>
      <geometry>
        <box size="22e-3 15e-3 20e-3"/>
      </geometry>
    </collision>
    <!-- cartriage sledge -->
    <collision>
      <origin rpy="0 0 0" xyz="0 -6.8e-3 2.2e-3"/>
      <geometry>
        <box size="22e-3 8.8e-3 3.8e-3"/>
      </geometry>
    </collision>
    <!-- diagonal finger -->
    <collision>
      <origin rpy="-0.5235987755982988 0 0" xyz="0 -15.9e-3 28.35e-3"/>
      <geometry>
        <box size="17.5e-3 7e-3 23.5e-3"/>
      </geometry>
    </collision>
    <!-- rubber tip with which to grasp -->
    <collision>
      <origin rpy="0 0 0" xyz="0 -7.58e-3 45.25e-3"/>
      <geometry>
        <box size="17.5e-3 15.2e-3 18.5e-3"/>
      </geometry>
    </collision>
  </link>



  <joint name="fr3_finger_joint1" type="prismatic">
    <parent link="fr3_hand"/>
    <child link="fr3_leftfinger"/>
    <origin rpy="0 0 0" xyz="0 0 0.0584"/>
    <axis xyz="0 1 0"/>
    <limit effort="100" lower="0.0" upper="0.04" velocity="0.2"/>
    <dynamics damping="0.3"/>
  </joint>



  <joint name="fr3_finger_joint2" type="prismatic">
    <parent link="fr3_hand"/>
    <child link="fr3_rightfinger"/>
    <origin rpy="0 0 0" xyz="0 0 0.0584"/>
    <axis xyz="0 -1 0"/>
    <limit effort="100" lower="0.0" upper="0.04" velocity="0.2"/>
    <mimic joint="fr3_finger_joint1"/>
    <dynamics damping="0.3"/>
  </joint>
  
</robot>

i I think there is no problem with my urdf file. I imported it in coppeliasim and it can be displayed normally, but it cannot be visualized using the pinocchio library.

Please help @stephane-caron @jviereck

[nim65s]

I think meshcat is currently not able to open .dae files. If you want to use the meshcat viewer, I think you should convert your visual meshes to another format.

[ManifoldFR]

On that note, we've been trying to get fixes for DAE meshes into the meshcat (JS) upstream repo: meshcat-dev/meshcat#170 for a little while now.

After that, they'll need to update the meshcat-python repo (and maybe do a release on PyPI) to point to the new meshcat backend.

For now, we have this branch on a fork of meshcat-python for which DAE files work. This is for your own reference, you may fork it yourself to have a working version, but we do not officially support it.