Chainable Admittance Controller

[pac48]

My primary goal is to reduce P-stop during trajectory execution.

This can be achieved via admittance control, but it will require some open source contribution. First, Denis' admittance controller (ros-controls/ros2_controllers#173) needs to be refactored into the new chainable controller pattern (ros-controls/ros2_control#667). Second, Denis' controller depended on a kinematics interface, but it never made it into ros2_control. Third, I need to make a PR and merge the refactored admittance controller into ros2_controllers. This can be broken into sub goals:

• Create a kinematics interface with KDL implementation under ros-control organization: (see Kinematics interface with KDL implementation ros-controls/kinematics_interface#1)
• Create a generic node interface for moveit2, so its kinematics/inverse kinematics can be used in the ROS 2 control loop: see (Enable moveit2 kinematics framework within ros2 control loop #1329)
• Create a moveit2 implementation for the kinematics plugin (probably will be located in moveit2 repo)
• Create admittance controller that conforms to the chainable controller interface (will merge into ros2_controllers)

Integrating the admittance controller into ros2_controllers will help ensure that it is supported long term.

[mhubii]

Hi @pac48. Random question, did you manage to run the chainable admittance controller with MoveIt in the end?

I am struggling to have MoveIt play along nicely with the joint names that are exposed by chainable controllers. E.g. MoveIt is configured to use joint_xyz, but chainable controllers expose controller_name/joint_xyz.

Thank you for the help!