Revision history [back]

I finally succeeded after 2 weeks of slipping. The problem was that although i was using an effort controller for my grippers, because i wasn't for the rest of the arm, gazebo was unable to calculate any lifting force (i don't know the specifics, this is just an observation).

I was using a gazebo service to map the movements of a ur5 from another simulation to gazebo, since there was no need for 2 controllers per joint. Now i am using trajectory control to map those same join states, which did require a bit of pid tuning.

Also i have frictional coefficients of 10 for mu1 mu2 and torsional coefficient.

Here's a urdf snippet:

  <!-- Add friction to right gripper -->
  <gazebo reference="right_inner_finger_pad_link">
    <collision name="right_outer_knuckle_link_fixed_joint_lump__right_inner_finger_pad_link_collision_3">
      <surface>
        <friction>
          <torsional>
            <coefficient>10.0</coefficient>
            <use_patch_radius>true</use_patch_radius>
            <patch_radius>0.05</patch_radius>
          </torsional>
        </friction>
        <contact>
          <poissons_ratio>0.5</poissons_ratio>
          <elastic_modulus>1e8</elastic_modulus>
        </contact>
      </surface>
    </collision>
    <mu1>10</mu1>
    <mu2>10</mu2>
    <maxVel>1</maxVel>
    <kp>1000000.0</kp>
    <kd>100.0</kd> 
    <fdir1>0 0 1</fdir1>
    <minDepth>0.0</minDepth>
    <maxContacts>100</maxContacts>
    <material>Gazebo/RedBright</material>
  </gazebo>