The Study Of Electro-hydraulic Servo Test Bench For Automobile Shock Absorber

With the improvement of living and comfort requirements, people’s requirementshave become more sophisticated in automobile shock-absorbing. The suspensionsystem plays a major role in automobile vibration attenuation, and shock absorbersare key components in determining performance for suspension system. Study andimproving the performance of the shock absorber has a very important meaning.Shock absorber performance’s promotion relies on the shock absorber’s performancecurve, and the design and development with experimental analysis on shock absorbersis essential for the study of shock absorber’s performance. In China today, mechanicalshock absorber test-bench is the most popular devices for shock absorber. Thetest-bench has a simple structure and high reliability, but the signal is single with bigerror and data processing problems. It is difficult to meet the test requirements ofshock absorbers. Electro-hydraulic servo shock absorber test-bench as ideal for shockabsorber test device is able to meet the stringent testing requirements of shockabsorbers. But at present this equipment at home is rare, most of them are dependenton imports from abroad and expensive. The main element of this project was to studyand develop a functional and relatively inexpensive electric-hydraulic servo shockabsorber test-bench. This kind of test-bench is not only able to complete shockabsorber temperature characteristics test, power characteristics test, speed and fatiguecharacteristics test, it can also provide various waveform what are needed by dampervibration test, such as simple harmonic wave, square wave, saw tooth wave and so on,and enable the system’s output with good follow to the input.The thesis first proposed design and analyze to the test-bench’s structure andhydraulic system. Hydraulic system principle diagram of the function of each part areanalyzed in theory, the analysis shows that it can satisfy the requirements of thesystem. And then Anti-shock hydraulic circuit is simulated with AMESim, betterresults were obtained. Electro-hydraulic servo system as the main part of theelectro-hydraulic servo shock absorber test-bench, this paper reference to national standard in the choice of performance parameters, then the load characteristics andperformance limits of electro-hydraulic servo system are studied. With theoreticalanalysis on electro-hydraulic servo system, its mathematical model and transferfunction of the system are completed. With the analysis of Matlab, the servo system’samplitude frequency and phase frequency characteristics meets the testingrequirements.Finally AMESim and Matlab/Simulink co-simulation analysis was carried out onthe test-bench’s electro-hydraulic servo system and correction is made to theamplitude’s attenuation of the signal in the system. The results show that the output ofthe test-bench has ideal meeting for input and shock absorber test-bench meets therequirements of the performance of the electro-hydraulic servo system.