The Fuzzy PID Control Research On All Terrain Crane’s Multibridge Steering System

Combined with the rapid transfer characteristics of truck crane and the load drivingcharaceristics of off-road tire crane,all terrain crane has superior lifting performance;muchmore capability of off road driving;compact structure;better driving stability;morebalanced of the whole weight distribution;as oil and gas for the suspentioncomponents,daming effect is much more obvious;automatically adjust the frame accordingto the statics of the road inorder to increase the driving performance and throughcapacity;much more capability of climbing;all-wheel steering,multi-axle driving withsmall turning radius;with a variaty of driving modes,using widely;better working stabilitywith big outtrigger span;exemped from the restriction of the front regions,capable of360-degree operation.There are some significant gaps mainly in lifting performance; product’s reliabilityand cutting-edge technoledge between domestic manufacturers and foreign ones.So theresearch and design of all terrain crain’s uniqe techenology of the chassis: hydropneumaticsuspension system and multi-bridge steering system means a lot.This subject mainly studies the Fuzzy-PID control of All terrain crane’s multi-bridgesteering system.First of all,according to the Ackerman steering principle, setting up theprototype of linear two degree of freedom model of All terrain crane’s multi-bridgesteering system,drawning the equation of vehicle movement state,as well as theparamenters that influence the characteristics that characterizing the vehicle’smovements,analysis the dynamic performance of multi-axle steering system in all-wheelsteering mode;then establishing mathematical model of single steering bridge actuatorcontrolled by proportional valve,using MATLAB/Simulink Fuzzy control module to setup the simulation model of single bridge steering control system,compared the resultssimulated by the normal PID control system.Finally, taking all terrain crain QAY50 as the experiment object.Testing the dynamicresponse of the all terrain crane’s steering system in different system pressure; differentload; different input of steering speed.Analysing the characteristics of the dynamic response, comparing the results and then drawing the conclusion of the three parametersthat mainly affect the steering system’s dynamic response. Comparing the experiementalresults and simulation results and then drawing the conclusion of the turning speed thatimpact the steering system’s fast and accuracy response.