Adaptive Control for Jib Crane System with Rope Hoisting and Uncertain Parameters

Abstract

This paper proposes a robust control system which consists of a robust controller and Model Reference Adaptive Control law for an uncertain jib crane system with rope hoisting. In this study, decentralized control comprised of two independent controllers is utilized to control the jib crane. To suppress the influences of system uncertainties e.g., variations of the rope length, nonlinear friction and so on, we design the control system composed of a linear robust controller and an adaptive law for the positioning system of the trolley. We apply the linear robust controller for the variation of system characteristics caused by hoisting the rope. On the other hand, the adaptive law is designed to estimate nonlinear friction. The characteristic of this study is to cope with nonlinear friction by using the robust controller with the adaptive law. The adaptive law is utilized for the estimation and compensation of nonlinear friction. Besides, we approximate nonlinear friction by a nonlinear function in the adaptive law. We show the exponential stability for the system with the proposed method by using Linear Matrix Inequality. Finally, we verify the effectiveness of the adaptive law by contrasting the proposed method with the only robust controller in the simulation of load transferring.