robot-calibration.md

Generating new calibarted URDF

If you already have a calibrated urdf you can skip the following steps for getting new calibrated URDF

• Follow home-robot calibration instructions to create a new calibrated urdf for your robot.

• Ensure the generated urdf has wrist_roll and wrist_pitch joints. If not, follow these documentations for re1 and re2 hello stretch for installating a dex wrist on the robot.

• Once you have a proper urdf add the following link and joint to the urdf

<link name="fake_link_x">
    <inertial>
      <origin rpy="0.0 0.0 0." xyz="0. 0. 0."/>
      <mass value="0.749143203376"/>
      <inertia ixx="0.0709854511955" ixy="-0.00433428742758" ixz="-0.000186110788698" iyy="0.000437922053343" iyz="-0.00288788257713" izz="0.0711048085017"/>
    </inertial>
  </link>
  <joint name="joint_fake" type="prismatic">
    <origin rpy="0. 0. 0." xyz="0. 0. 0."/>
    <axis xyz="1.0 0.0 0.0"/>
    <parent link="base_link"/>
    <child link="fake_link_x"/>
    <limit effort="100.0" lower="-1.0" upper="1.1" velocity="1.0"/>
  </joint>

• Also, modify the parent link of joint_mast joint from base_link to fake_link_x. The joint should finally look like this

<joint name="joint_mast" type="fixed">
    <origin xyz="-0.06886239813360509 0.13725755297906447 0.025143215009302215" rpy="1.5725304449603004 0.0027932103811125764 0.013336895699597295"/>
    <axis xyz="0.0 0.0 0.0"/>
    <parent link="fake_link_x"/>
    <child link="link_mast"/>
  </joint>

URDF Location: After that replace the strech_manip_mode.urdf in ok-robot-hw/hab_stretch/urdf/ directory with this new calibrated urdf.