Mechanical Parking Arm Hydraulic System Design And Simulation Research

With the development of the society, the contradiction between the rapid increase in number of automobiles and limited parking facilities is more and more severe.The main method to solve the question is to build the mechanical parking equipment. There is a high level of technology of vertical lifting gate type automatic mobile parking.Tey key of technology is the arm of transporting automobile about the mechanical parking.The basis of the parking arm is hydraulic drive.The direction and flow of fluid is controled by electro-hydraulic proportional valve, and the purpose that to control the speed and the direction of the motor and the lifting cylinder is received.The main work of this thesis is to design the hydraulic system of the mechanical parking arm. Firstly, by analyzing the force of driving wheel and driven wheel of walking mechanism, the maximum load of the hydraulic system is found.The kinematics and force of lifting arm have been simulated by ADAMS.The speed and displacement curve and hydraulic cylinder bearing the maximum load are obtained from the simulation results.According to the maximum of the lifting mechanism and walking mechanism load and the functional requirements of the lifting arm,this thesis mainly focuses on the design of the hydraulic system,component choosing and checking.The walking hydraulic system,lifting hydraulic and secondary action system is designed.Pressure compensation control is used in walking and lifting hydraulic system.The purpose is to reduce load change influence on the velocity of actuators and to improve the accuracy of the speed control.In additon,synchronization value is used in lifting hydraulic system to ensure speed synchronization of the two lifting cylinders. The characteristics of speed regulation and pressure compensation of lifting and walking hydraulic systems and the characteristics of synchronization of the two lifting cylinders are simulated and analyzed by AMESim software.The result shows that the systems have good speed regulation characteristics, the pressure compensation control can greatly reduce the impact of load changes.the synchronization accuracy of the two lifting hydraulic cylinder also reach to the required.