Dynamically tuning [joint_trajectory_controller] PID gain

[JinbaoXiong]

In ros1, the change of P parameters of effort_controller/JTC in runtime can be use to change the force of the joint. But in ros2, I have tried to change the P parameters using the /set_parameters service provided by the JTC in runtime, but the forece still remain same.
I just wonder, when the JTC in ros2 can have the ability to accept the change of the PID gains in runtime like ros1?

[christophfroehlich]

Yes, in iron and rolling.
Iron might not be released yet, you have to build it from source.
For humble you can use the the branch from this PR and build it from source.

[christophfroehlich]

Sorry, for iron it was already released with 3.18 too.

[JinbaoXiong]

thanks a lot!!!!