Research And Experimental Of Crane Adaptive Fuzzy PID Anti Sway Control

In order to reduce the cost of manual handling,the demand of cranes is gradually increasing in construction sites,ports and docks.However,the evaluation factors of crane are operation safety and operation efficiency.And the quality of the crane lifting goods is large,so there are high requirements during crane operation.Crane operation efficiency has a direct impact on the production efficiency of enterprises.In the process of crane operation,the swing of lifting load is the most important factor affecting the safety and efficiency of crane operation.Firstly,the dynamic mathematical model of the gantry crane with three degrees of freedom is established in this paper.The mathematical model of the lifting mechanism is regarded as a 2-DOF underactuated system in the motion plane of the vertical lifting and trolley running directions of the gantry crane.2-DOF is the swing of the lifting load and the linear running freedom of the trolley,and the lifting mechanism is the mass.The 2-DOF underactuated system is mainly composed of lifting trolley,lifting mass and wire rope.According to the change of kinetic energy and potential energy of the whole system composed of crane and lifting mass and the swing degree of freedom and linear motion degree of freedom in the plane,the Lagrange equation of the system is constructed by the dynamic analysis method.Secondly,two controllers are constructed based on the adaptive fuzzy PID control algorithm in this paper.And one is the displacement fuzzy PID controller of the lifting trolley moving in a straight line and the other is swing angle fuzzy PID controller for swing of lifting mass.The linear driving force of the trolley is provided by the output of the displacement controller based on the fuzzy algorithm,so the displacement fuzzy PID controller can ensure that the trolley can stop at the target position accurately.The dynamic response of the swing of the lifting mass is restrained by the output of the swing angle controller based on fuzzy algorithm.The controller takes the displacement deviation and deviation change rate of the trolley and the swing angle deviation and deviation change rate of the load point as the input signals.In this paper,Gaussian membership function is used as the membership function of input signal,and fuzzy control rule base is established based on expert experience and experimental results.The center of gravity method is used to make fuzzy judgment on the fuzzy set of the fuzzy control algorithm,and the accurate signal is input to the displacementswing angle PID controller.Thirdly,numerical analysis method is used to study the dynamic response of the trolley displacement and swing angle of lifting mass.Different working conditions are analyzed in the whole process as follows.The results of free and controlled swing angle of lifting load are analyzed with different swing angle.The results of displacement controller and displacementswing angle controller are analyzed with different lifting mass.Compared with the control methods,when the fuzzy PID controller is used in the displacement controller of the trolley and the swing angle controller of the lifting load,the trolley motion state is much more stable.At same time,the maximum swing angle is 2.7° and the tracking performance of the trolley displacement curve and the load swing angle curve are the best in the different working conditions.Finally,based on the 2-DOF(2 degrees of freedom)mathematical model of the trolley and the mass point system of the crane,a 2-DOF driving control system test-bed is built.The embedded control system of crane takes STM32F103 as the control core of microprocessor.The dynamic response and real-time state monitoring system of crane trolley and lifting mass point which is use for anti sway control is established in Lab VIEW.Based on the 2-DOF driving control system test-bed,this paper studies the displacement of the trolley and the swing angle of the lifting mass point of the crane system driven by different controllers.The test results show that when the displacement-swing angle fuzzy PID controller is used in the control system of the crane,the swing of the lifting load caused by the acceleration of the trolley and external excitation can be quickly suppressed with the condition that the trolley’s straight-line running time is 25 s and the maximum swing angle of the lifting mass is 1°.