Get_joint_torques deprecated, but cannot find equivalent function

Hi, I try to add a weight to a robotic arm and measure the simulated joint efforts that when the robot is moving the weight. I currently use get_joint_torques(), since get_applied_joint_efforts() does not yield the desired result, as I do not want to apply torques and thus not measure applied torques, but the torques induced only by gravity and the robot movement, being controlled via joint position Articulation actions.

On a side note, when moving the weight via positional Articulation actions, the result given by get_joint_torques() does match the groundtruth real world data perfectly when it comes to the static forces, however, it fails to capture the dynamic forces (simulated forces in blue, measured in orange)
measured_torques_joint_2

Hi @kilbraun ,

Yes this is a known issue. In the current release, it’s best to approximate the drive forces using the spring-damper equation. It won’t match perfectly because we use an implicit integration in the engine, but should be close in general.

The good news is that in the next IsaacSim release, we added a feature that exposes the link joint, and the dof forces transmitted from the parent to the child link, from which you can read out the drive forces (assuming that no joint friction or other dof forces are acting at the same time).

Philipp