The Investigation On Control Law Of Automobile Magnetorheological Semi-active Suspension And Design Of Test Bench

The control of automobile magneto-rheological(MR) semi-active suspension is one of the highlights in vehicle dynamics. Most of the previous researches on MR semi-active suspension mainly rely on digital simulation. Because of the higher cost and longer time period in field test of vehicle with MR damper, it is urgent to investigate the test bench to conduct the investigation. In this thesis the digital simulation of semi-active control law is conducted and the test bench of 1/4 vehicle MR semi-active suspension is designed. The main contents and conclusions are summarized as follows:(1)The dynamic analysis of automobile MR semi-active suspension: The suspension performance evaluation indicators are determined and the suspension model is simplified. The 1/4 vehicle MR semi-active suspension model and road input model are conducted.(2)The investigation on control law of MR semi-active suspension: The mechanical models of sky-hook control, hybrid control and fuzzy control are built.The control results of the three law are analyzed separately in the Matlab/Simulation environment. Furthermore, the advantages and disadvantages of three law are compared.(3)The response of different factors on MR semi-active suspension: The factors including system parameters, vehicle speed and road input are discussed.(4)The test bench design of automobile MR semi-active suspension: The test bench overall design is conducted and its main parts are determined according to the performance requirements of semi-active suspension. As the key part of the test bench design, the platform structure design is carried on in detail in the aspects of sliding part,beam,wheel fixing device and spring. At the last, sensors choosing and the installation and debugging of test bench are explained.The test bench of 1/4 vehicle MR semi-active suspension in the thesis is commonly useful, simple and reliable. And it could be used to validate the theoreticalresults and to improve the control law, which would be beneficial to the semi-active control law investigation. The response of different factors on MR semi-active suspension is also discussed in the thesis.