The Fuzzy PID Control And Study Of The Semi-active Vehicle Suspension

With the rapid development of national economy, the overall construction of expressway network and the great improvement of people's living standard, automobiles have gradually come into people's life and work, and become an indispensable means of transportation. Meanwhile, people have made greater demands on the comfort and security of automobiles. The Suspension System is the very important components to ensure vehicles travelling comfort and safety. In this paper, the writer has done the simulated and experimented research on the quarter-car suspension system which equipped the magneto-reological damper.Firstly, a vehicle vibration model of 1/4 body with 2 degree-of-freedom is created, which is based on the vehicle dynamics theory. Considering the influence of the input disturbance, a mathematical description of road surface irregularity is established, which is the model of integral white noise. After the modeling of input, the semi-active suspension sky control strategy and Self-adapt Fuzzy PID controller are designed respectively and the computer simulations are built with Matlab7.0 individually, we simulated the quarter-car semi-active suspension system, and achieved the better results.Second, this paper proposes a method of using the RTWcode generation tool to convert Matlab/ Simulink to the C/ C++ code,and loaded into the TMS320 C6713evm board.Accordingly the system' s model is constructed conveniently by using simulink. This can not only avoid the problem of low simulation speed of the model in Matlab/Simulink circumstance, but also deduce the workload of the programming engineer. In addition, the converted C code can run independently out of Matlab circumstance, which expands the use domain of the converted C code by this method.Finally, we present an experiment on a test rig of quarter car model equipped MR damper, and use the LabVIEW software to do a research on the fuzzy PID controller of the semi-active suspension system. Through the experiment we gain the acceleration and the suspension deflection of the sine excitation. The results proved that the fuzzy PID strategy is efficient for the semi-active suspension system, it improved the performance of suspension.