Fuzzy Controller Research And Development Of Semi-active Suspension Based On DSP

With the improvement of people's living standard, people need better quality of the vehicle's comfort and riding stability. It has become more difficult for traditional passive suspension to meet the requirements. Active-suspension overcomes the disadvantages, however, the cost of manufacture and use is high. Semi-active suspension is a comprise solution between the passive suspension and active suspension. Compared with the active suspension, it has simpler structure, higher stability and lowed cost. And it can also reduce the vehicle's upright acceleration. For this reason, the research on semi-active suspension as a new technology has attracted more and more people's attention.The paper aims to design the DSP controller based on the simulation research on the damping adjustable shock absorber. The major contents are as following:Chapters One and Two summarize the categories of suspension and the control methods of semi-active suspension , and compare the advantages and disadvantages. Based on Bingham fluid model of the hydrodynamics theory, the paper attempts to establish the mathematic model of damping adjustable shock absorber in Chapter Three. And through simulation study, the author gets the characteristic curve of damping adjustable shock absorber. In Chapter Four, the researcher conducted the research on a quarter vehicle's model, the results of which may supply references to the control algorithm study. Chapter Five is the study on the control algorithm study. In this chapter, the researcher first conducted the simulation research on PID control, fuzzy control and adaptive fuzzy control with MATLAB SIMULINK toolbox. And through the comparison of the results, the author adopted the adaptive fuzzy control as the control law of the controller at last. Chapter Six introduces the controller design. The controller design includes: the selection of step motor and the selection of the main CPU of the suspension controller; the design and the analysis of the reliability of the PCB, including power circuit, peripheral circuit and step motor driver circuit design; the development of control software with the adaptive fuzzy control method. And the preliminary experiment for validation has been done at the lab.