Obstacle Avoidance for Non-Holonomic Mobile Manipulator Using System's Redundancy with Control Barrier Functions

Abstract

This paper proposes a new method to guarantee safety in mobile manipulator systems. A system including a fixed-base manipulator mounted on a mobile platform is regarded as a mobile manipulator, which requires complex design and control. First, the trajectory tracking problem of a non-holonomic mobile manipulator (NH-MM) is considered based on the decoupling dynamic control for independent control of end-effector and mobile platform position. Then, an obstacle avoidance method based on the control barrier function (CBF) is proposed. The objective is to utilize the system's redundancy for obstacle avoidance by the mobile platform of the NH-MM. By adopting this approach, the mobile platform can successfully navigate around obstacles while the end-effector continues to perform its intended task autonomously. The effectiveness of the proposed method is demonstrated through simulation results.