[Bug Report] Unable to access get_measured_joint_efforts (AttributeError)

[lorepieri8]

Describe the bug

Unable to access get_measured_joint_efforts (AttributeError)

Steps to reproduce

self._robot = Articulation(self.cfg.robot)
print("joint efforts: self._robot.root_physx_view.get_measured_joint_efforts())

AttributeError: 'ArticulationView' object has no attribute 'get_measured_joint_efforts'

Additional context

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Checklist

• [x ] I have checked that there is no similar issue in the repo (required)
• [x ] I have checked that the issue is not in running Isaac Sim itself and is related to the repo

Related: #1867

Acceptance Criteria

Add the criteria for which this task is considered done. If not known at issue creation time, you can add this once the issue is assigned.

• Able to access get_measured_joint_efforts or to get the effort of individual joints (joint forces in the DOF motion direction)

[kellyguo11]

The get_measured_joint_efforts API is an Isaac Sim Articulation class API. To access the physics tensor API directly from self._robot.root_physx_view, you can use get_link_incoming_joint_force. Available tensor APIs are documented at https://docs.omniverse.nvidia.com/kit/docs/omni_physics/latest/extensions/runtime/source/omni.physics.tensors/docs/api/python.html#module-omni.physics.tensors.impl.api

[lorepieri8]

Thanks for your reply.

get_link_incoming_joint_force is not what I need, it seems to be the same as self._robot.data.body_incoming_joint_wrench_b, which is exposed in Isaac Lab and returns the 6d wrench (3 forces + 3 torques) at each DOF.

But following your link I found get_dof_projected_joint_forces and get_dof_actuation_forces, which seems what I need to isolate the external force acting on each joint in the DOF motion direction.

I will test and report back, but this should solve the issue.