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For the TUM PR2, I adjusted the urdf file in /etc/ros/distro/urdf/robot.xml to compensate for the error, it works fine now. Looks like this for us:

'<transmission name="torso_lift_trans" type="pr2_mechanism_model/SimpleTransmission"> '<actuator name="torso_lift_motor"/> '<joint name="torso_lift_joint"/> '<!--mechanicalReduction>-52143.33</mechanicalReduction--> '<mechanicalReduction>-47532.66</mechanicalReduction> '</transmission>

So i measured maximum and minimum encoder value via 'rostopic echo /motor_trace/torso_lift_motor' along with actual positions. You can then guess what the actual mechanicalReduction should be.

For the TUM PR2, we had a similar issue, it turned out to be a calibration problem of the spin. I adjusted the urdf file in /etc/ros/distro/urdf/robot.xml to compensate for the error, it works fine now. Looks like this for us:

'<transmission name="torso_lift_trans" type="pr2_mechanism_model/SimpleTransmission"> '<actuator name="torso_lift_motor"/> '<joint name="torso_lift_joint"/> '<!--mechanicalReduction>-52143.33</mechanicalReduction--> '<mechanicalReduction>-47532.66</mechanicalReduction> '</transmission>

So i measured maximum and minimum encoder value via 'rostopic echo /motor_trace/torso_lift_motor' along with actual positions. You can then guess what the actual mechanicalReduction should be.

For the TUM PR2, we had a similar issue, it turned out to be a calibration problem of the spin. spine. I adjusted the urdf file in /etc/ros/distro/urdf/robot.xml to compensate for the error, it works fine now. Looks like this for us:

'<transmission name="torso_lift_trans" type="pr2_mechanism_model/SimpleTransmission"> '<actuator name="torso_lift_motor"/> '<joint name="torso_lift_joint"/> '<!--mechanicalReduction>-52143.33</mechanicalReduction--> '<mechanicalReduction>-47532.66</mechanicalReduction> '</transmission>

So i measured maximum and minimum encoder value via 'rostopic echo /motor_trace/torso_lift_motor' along with actual positions. You can then guess what the actual mechanicalReduction should be.