MOBILE MANIPULATOR MOTION PLANNING FOR MULTIPLE TASKS USING GLOBAL OPTIMIZATION APPROACH

A mobile manipulator can perform various tasks efficiently by utilizin g mobility and manipulation functions. The coupling of these two funct ions creates a particular kinematic redundancy introduced by mobility, which is different from that introduced by extra joints. This redunda ncy is quite desirable for dexterous motion in cluttered environments, but it also significantly complicates the motion planning and control problem. In this paper we propose a new motion planning method for mo bile manipulators to execute a multiple task which consists of a seque nce of tasks. The task considered in this paper is that the end-effect or tracks a prespecified trajectory in a fixed world frame. In a multi ple task, the final configuration of each task becomes the initial con figuration of the next subsequent task. Such a configuration is known as a commutation configuration, which significantly affects the perfor mance of the multiple task. We formulate the motion planning problem a s a global optimization problem and simultaneously obtain the motion t rajectory set and commutation configurations. In the formulation, we t ake account of the case that the platform has a non-holonomic constrai nt as well as the one that the platform has a holonomic constraint. Si mulation results are demonstrated to verify the effectiveness of the p roposed method.