Anti-swing and positioning control of tower cranes based on adaptive hierarchical sliding mode
To solve the anti-swing positioning control problem of a tower crane with two-stage swing structure in three-dimensional space,an adaptive hierarchical sliding mode control scheme is proposed considering the combined operation condition of luffing and slewing.Firstly,the tower crane system is divided into positioning subsystem,one-stage swing angle subsystem and two-stage swing angle subsystem,and a hierarchical sliding mode control law is designed;then an adaptive law is designed to improve the adaptability of the system to parameters and the suppression performance of external interference;finally,the stability of the system is verified and the system is simulated.The simulation results show that when the system is subjected to instantaneous disturbances,the adaptive law estimates the size of the disturbance,and the controller quickly respondes by adjusting the control force/torque to offset the instantaneous disturbance,so that the instantaneous disturbance does not have a significant impact on the position of the system and the swing angle of the hook and load.The adaptive layered sliding mode controller here suppresses the swinging of hooks and loads caused by instantaneous disturbances with good robustness.