Using adaptive control to solve the tracking problem for a mobile manipulator

Abstract

In this paper, the control of a mobile manipulator for tracking smooth 3D-curved welding trajectory is discussed. This case can be found in any metal processing factories such as ship building factories and pre-fabricated metal structure factories. The mobile manipulator is made up of a multilink manipulator and a two-wheeled mobile platform. The kinematic modeling and the constraints for both the platform and the manipulator are discussed. Based on these modeling, an adaptive control algorithm for the welding mobile manipulator is proposed. A candidate Lyapunov function is also introduced for proving the stability of system upon the adaptive algorithm. For increasing the flexibility of system, the control of system with unknown parameter such as the arc length of the torch is considered, and an update control law based on the adaptive back-stepping method is proposed. In this paper, the numerical simulation results are shown to illustrate the validity of the proposed algorithm. The experiments are also performed for getting the good values of parameters and proving the feasibility that a mobile manipulator is applied to a 3D smooth curve welding task.