The nexus_robot_controller package was introduced when we were still using ros2_controls on humble where controller_manager was not implemented as a lifecycle node. In practice, we didn't rely on the lifecycle feature and hence launch files start the upstream controller_manager and no the nexus_robot_controller node.
Since then the controller_manager has been reimplemented as a lifecycle node so there is no need for nexus_robot_controller. See https://github.com/ros-controls/ros2_control/blob/master/controller_manager/CHANGELOG.rst
The
nexus_robot_controllerpackage was introduced when we were still usingros2_controlsonhumblewherecontroller_managerwas not implemented as a lifecycle node. In practice, we didn't rely on the lifecycle feature and hence launch files start the upstreamcontroller_managerand no thenexus_robot_controllernode.Since then the
controller_managerhas been reimplemented as a lifecycle node so there is no need fornexus_robot_controller. See https://github.com/ros-controls/ros2_control/blob/master/controller_manager/CHANGELOG.rst