Controller design for a rail mounted inspection robot manipulator

This paper focuses on the controller design of the RoboShip manipulator. The manipu- lator has been designed to inspect ballast wa- ter tanks autonomously. The goal of this pa- per is to design and implement the controller on the manipulator that is able to steer the end-effector to a predefined setpoint. The manipulator needs to remain stable when the end-effector contacts the wall of the bal- last water tank to take a measurement. The designed controller is implemented on the RoboShip manipulator and tested in both free space and in contact with the environ- ment. Experiments indicate that the manip- ulator is capable of operating both in free space and in contact with the environment. Keywords: Operational space, redundant manipu- lator, ballast water tank, impedance control, PID- controller, gravity compensation