Extended RMRC and its Application to the Motion of a Mobile Manipulator

Abstract

This paper proposes a method calculating joint velocities of a robot which moves the end effector at desired velocity where some of the joint motions are constrained. It is an extension of the Resolved Motion Rate Control (RMRC) method which has been used in cases where there is no constraint on the motion of the joints. The proposed method is called the extended RMRC (E-RMRC). Though the E-RMRC is expressed in a simple form, application of the E-RMRC to a specific robot system is not straightforward and sometimes calls for elaboration. So, the paper describes the application of the E-RMRC to the motion of a mobile manipulator. The example explains how the proposed method is applied to find the joint rate to move the end effector of the mobile manipulator through a desired trajectory while the trajectory of the mobile base is constrained. The application is tested and verified through simulation and experiments.