Improving control performance of a container crane using adaptive friction compensation

This paper investigates an adaptive control scheme for container cranes that transport containers between a container ship and trucks. Three unknown parameters (the mechanical friction between the trolley and the guide rails, the mass per unit length of the rope, and the payload mass) are estimated. Since the rope of the crane is flexible, an axially moving string equation is introduced to model the rope dynamics. The Lyapunov method is used to assure the uniform stability of the closed loop system. The experimental results demonstrate the effectiveness of the proposed control scheme.