[JTC] Is acceleration-only command interface setup useful?

[christophfroehlich]

The validator does not allow acceleration-only command interfaces:

ros2_controllers/joint_trajectory_controller/include/joint_trajectory_controller/validate_jtc_parameters.hpp

Lines 33 to 36 in 6851df1

	// Check if command interfaces combination is valid. Valid combinations are:
	// 1. effort
	// 2. velocity
	// 2. position [velocity, [acceleration]]

I'm not sure if this would make sense, i.e., if there is any robot type with acceleration-only interface, but I think JTC could work with it.

• Should we allow it?
• If not -> I'll clarify that in the docs, because this is not clearly described there.

[destogl]

You are right. If we have effort, then acceleration is not necessary. People using direct control of joint moments will use rather effort than acceleration.

So I am arguing to disable that.

[christophfroehlich]

Thanks for the info, I'll write an update for the docs for clarification.