Research On The Anti-swing And Positioning Control System Of Bridge Crane

Bridge crane is an important handling tool for materials.During the transport of goods in ports,wharfs and warehouses,eliminating or suppressing the swinging of the crane’s load is necessary.In this paper,the following research is carried out on the problem of anti-swing control of bridge cranes.Firstly,considering that the bridge crane is a typical underactuated system,we establish the nonlinear three-dimensional mathematical model of the crane system by using the Lagrange equation and then linearize it.The validity of the dynamic model is verified by the latter simulation experiment.Secondly,the load wobble mechanism of the crane is studied by the conventional PID algorithm.On this basis,in order to adapt to the change of model parameters,the fuzzy algorithm is used to adjust the parameters of PID algorithm,and the comparative analysis is carried out in MATLAB/Simulink.The results show that both of them can achieve the anti-swing and position control of the crane system effectively.Compared with traditional PID control,fuzzy self-tuning PID control method has strong robustness in terms of cart position,rope length,load quality and external disturbance,but this method still has some limitations.Thirdly,aiming at the anti-swing positioning control of two dimensional overhead traveling crane,a first order dynamic sliding mode variable structure controller is designed,and it is compared with time-varying sliding mode control and multi sliding mode equivalent control.The results show that the designed controller has the best effect,it can make the load location more fast and accurate without overshoot,and has strong anti-swing ability.At the same time,the improved Sigmoid function is used to replace the traditional Sgn function in the design of the reaching law,which effectively suppresses the buffeting of the driving force.Through the simulation experiments under different load mass,different coefficient of friction and external disturbance,it is concluded that the first-order dynamic SMC has much robustness than other traditional control methods under internal parameter variations and external disturbances,it means that the method is more practical.Fourthly,a platform is designed for the physical experiment of the bridge crane.By using the sliding mode control strategy and the PID algorithm,we carry out some physical experiments and realize the positioning and anti-swing control of the crane.At the same time,it is proved that the designed sliding mode controller is superior to the traditional PID control,and it shows strong robustness to changes in load mass and cart position.