Application of Internal Model Control Based on Inverse System Method to Anti-swing of Crane

For nonlinear underactuated horizontal moving process of bridge crane system,the nonlinear inverse system method is used firstly to convert the bridge crane system into a pseudo-linear system,then an internal model controller is designed based on linear control theory to obtain the precise position.At the same time,an angle feedback controller is designed to make the angle damp out.Finally,a comparison is made with conventional PID(proportional integral differential) and fuzzy controller respectively.Experiment results demonstrate that the proposed strategy can guarantee no positioning errors and quickly damping-out of angle,it has good abilities of anti-disturbance and robustness,and its control performance is better than that of PID and fuzzy control.