C++ API for JointController

[mogumbo]

Desired behavior

C++ API for JointController, JointPositionController, and JointTrajectoryController similar to the API found in gazebo::physics::JointController from Gazebo Classic. Specific methods I have used from gazebo::physics::JointController are GetJoints, GetPositions, GetPositionPID, GetVelocities, GetVelocityPIDs, SetPositionPID, SetPositionTarget, SetVelocityPID, and SetVelocityTarget.

Alternatives considered

You can interact with joint controllers using gz-transport, but results of these actions are not necessarily immediate and add complexity to your code if you need to receive a response.

Additional context

I'm currently using gz-sim8 on Ubuntu 24.04.

[scpeters]

I can imagine creating components like JointPositionControlTarget, JointVelocityControlTarget , JointPositionControlPID, JointVelocityControlPID that the joint control systems can try to read from the ECM in addition to gz-transport topics.

Would it also make sense to create a JointController C++ object similar to gz::sim::Model or gz::sim::Joint?