Study On Hydraulic Servo Control System Of Air Shock Absorber Test-bed

Since the air shock absorber was born, people tried their bests to raise the lifetime ofit. The main influence factor of lifetime is the lifetime of air bag. According to the statisticsof broken air shock absorber,90％of breaks focus on the air bag. The study on air shockabsorber test-bed start lately in our country, and in early times depending on the forexternal devices. In the recent years, designing and study on air shock absorber test-bedhas made great progress in domestic. However, the domestic air shock absorber test-bedhas not imitated the situation of gravity, consequently, the study on air shock absorbertest-bed with gravity has not come true. It is shown that the air shock absorber test-bedcontrols unsymmetrical hydraulic cylinder through electric hydraulic servo control valve,goes up and down, and press on air shock absorber repeatedly. The biggest load is15T anddoes the expansion movement repeatedly with the frequency of3.3Hz and half allowablemaximum value as amplitudes. The test-bed is mainly used to make500thousand times offatigue properties experiments of air shock absorber. The test-bed is a either position orforce servo control system, consequently, this is an extreme complicated mechanicalelectric hydraulic fixed system. It refers to hydraulic transmission, control theory and othersubjects.It is mainly showed study on air shock absorber test-bed hydraulic servo system in thethesis. Firstly, the control case is determined, and the test-bed is controlled byunsymmetrical hydraulic cylinder through controlled by proportional servo valve. And thenthe transmission function of valve control unsymmetrical cylinder is derived throughmassive theoretical analysis. The linear and nonlinear mathematics models of position and force servo control system are built. Eventually, the air shock absorber test-bed issimulated through MATLAB/Simulink module library in the tool box, and made static anddynamics analysis; PID is revised by the simulation results and the best PID controlparameter is searched.