Concave Semi-trailer Hydraulic System Design And Optimization Of The Steering Mechanism

With the continuous development of the logistics industry in China, the semi-traileras the main carrier of road transport is moving in the direction of diversification forward.Hydraulic semi-trailer has the mechanical structure which is owned by the ordinarysemi-trailer. Because it has the advantages of rising and falling, flexible steering, easy tooperating, it has been used more and more widely.The purpose of this study is based on customer requirement to design a kind ofsemi-trailer which can transport huge tank. According to the phenomena of hydrauliccylinders lifting out of sync and vibration, this paper improves the hydraulic system anddoes some simulation analysis and experimental research. According to the steeringphenomena of tire wearing and cornering, this paper optimizes the steering mechanism.Firstly, this text introduces the vehicle structure. Setting up the three-dimensionalmodel of the telescopic frame and front and rear gooseneck by using Pro/E and analyse byusing ANSYS finite element analysis software. The analysis results fully comply with thedesign requirements through the stress and the strain experimental analysis. Thesuspension structure and frame are fully comply with the actual working conditionrequirements.Secondly, according to the phenomena of hydraulic cylinders lifting out of sync andvibration, this text improves the synchronization loop based on diverging and collectingvalve and improves the balanced loop based on FD balancing valve. Calculating andselecting the hydraulic components by analyzing statics and kinematics of the liftingmechanism model. The feasibility of the new hydraulic control scheme and the correctnessof the simulation model are verified through the AMESim simulation and experimentalresults.Finally, this text analyses the kinematics of the steering mechanism and establish themathematical model of the steering rod and steering arm. By comparing of thedeterministic optimization, the robustness optimization and the reliability-based robustdesign optimization, this text optimizes the design of the steering mechanism by using reliability-based robust design optimization and MATLAB software. The simulationresults and the factory tests shows that steering performance has been improved.