Currents as efforts

[urfeex]

Manual backport of #1551 that doesn't change the behavior for existing distributions.

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Note

Medium Risk
Changes joint effort semantics and RTDE output recipe composition; misconfiguration or mixed launch defaults could surprise consumers of joint_states, though defaults aim to preserve motor-current reporting.

Overview
Adds a use_currents_as_efforts hardware parameter (and launch/xacro wiring) so joint effort state can come from either actual_current (motor currents, default / prior behavior) or actual_current_as_torque on PolyScope ≥ 5.23.0 / 10.11.0 when the parameter is false.

The hardware interface now builds RTDE input/output recipes in memory, optionally appends actual_current_as_torque to the output recipe, fails configure if torques are requested on unsupported software, and selects the correct RTDE field in read(). Docs clarify that joint_states effort is currents by default and how to get true torques.

ur_control.launch.py exposes the new launch argument (default false in that file); ur_rsp.launch.py and xacro default true to preserve existing deployments without changing effort semantics.

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Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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Missing param selects torque mode

Medium Severity

If use_currents_as_efforts is absent from hardware parameters, map lookup yields an empty string and the flag stays false, so the driver requests torques. For custom URDFs that predate this parameter, that changes prior currents-as-efforts behavior and can fail on older robot software.

Additional Locations (1)

• ur_robot_driver/include/ur_robot_driver/hardware_interface.hpp#L403-L404

 

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