基于PI建模和反步滑模控制的主动波浪补偿策略OACSTPCD

Influenced by wind,waves,and surges,offshore crane ships can suffer from serious changes in ship attitude,resulting in changes in the posture of the crane and cargo,which has potential safety hazards to cargo and personnel.The stability control of the wave compensation plat-form can effectively reduce the motion impact on the safety,stability and accuracy of offshore operations,which is extremely important for the precise loading of offshore equipment on floating cranes.Aiming at the difficulty in modeling and inaccurate control caused by the hysteretic non-linearity of the compensation platform,an active wave compensation strategy is proposed based on PI modeling and backstepping sliding mode control in this work.Firstly,the hysteresis effect curve of the compensation system is obtained through experiments,the PI hysteresis model is es-tablished by analyzing the system hysteresis loop.The parameters of the PI hysteresis model are identified by the recursive least square method,which supports the formulation of the system model.In succession,the backstepping control compensation method is designed based on Lyapun-ov stability,and the initial control speed is accelerated by combining the sliding mode control law.Finally,the backstepping sliding control meth-od is applied to the compensation system.The performance of the proposed method is validated by simulating the response under regular and ir-regular waves in MATLAB.The resulting control strategy is further applied to perform compensation movement by driving the electric cylinder(based on the motion control card Control the servo motor).The real-time data of the system movement is collected through the sensor,which is fed back to the control strategy to form a closed loop,aiming to confirm the performance of the compensation platform under the both the regular and irregular waves.The experimental results show that the established PI hysteresis model of the Stewart platform achieve desired accuracy,and the backstepping terminal sliding mode control algorithm is able to compensate the wave motion in the actual control of the Stewart platform with high-performance.Compared with PID,backstepping method,reinforcement learning and other control methods,the proposed method can provide high performance to meet the practical requirements.