| As an important cargo handling machinery,bridge cranes have a wide range of applications in many fields such as machinery manufacturing,logistics,construction and other fields.Due to the flexible system dynamics of the trolley-steel cable-slinger of the crane,the crane is very prone to the phenomenon of swinging the spreader during the operation,which affects the positioning time and positioning accuracy of the load.Therefore,it is important to study how to eliminate the swaying phenomenon of the spreader during the operation of the crane,which is of great significance for improving the efficiency and accuracy of the crane.This paper mainly studies the anti-swing and positioning control system of the crane.Firstly,the structure of the bridge crane and its load characteristics are described.On this basis,the dynamic model of trolley and spreader which part of the bridge crane is established by Lagrangian method,and the transfer function is obtained and is analysis for dynamic characteristics of model parameters under the driving force.Because the crane model belongs to the under actuated control model,based on the analysis of the crane dynamics model and performance requirements,the feedforward and feedback strategies of the crane anti-swing control are studied.The feedforward control part,shapes the input pulse of the crane running without swing angle based on the input shaping control,,and obtains the acceleration amplitude and time lag of the motor to achieve the purpose of improving the crane operating efficiency and eliminating the swing angle of the spreader.Considering the mathematical modeling error of the crane and the environmental interference factors,fuse feedback control to eliminates the residual angle of the system and the disturbance swing angle.The fuzzy control theory was adopted in the feedback control part.By establishing the trolley displacement fuzzy controller and the anti-swing fuzzy controller,the output is linearly proportionally superimposed and normalized to realize the positioning and anti-shake control.At the same time,the hoisting fuzzy controller is established to realize the load height control.Finally,based on the two control technologies combined with the design of the closed-loop anti-swing control strategy of the crane,the crane spreader angle is eliminated and the positioning accuracy of the trolley is improved.In order to obtain the real-time attitude angle of the crane required for closed-loop feedback,this paper designs the crane spreader attitude detection module and the upper machine attitude calculation program according to the anti-swing control system requirements.The program adds complementary filtering to eliminate the sensor’s principle error,and verified through experiments.Module attitude detection performance.Finally,the anti-swing test bench was built to verify the anti-shake control strategy.The experimental results show that the control strategy and the corresponding control program have good anti-swing and positioning control effect on the experimental bench. |
