| As automobile running velocity's great increase and road traveling consistency's rapid accretion,the happening ratio of traffic accident has ascended continuously. Wholly and reliably improving automobile's active safety performance offers the challenge for automobile designer and researcher as an impendent and difficult task. Some automobile manufacturers have already announced their plans to introduce some high technology devices such as ABS (Anti-lock Braking system),ASR (Acceleration Slip Regulation) and VDSC (Vehicle Dynamics Stability Control) on all their models,which are developed to improve vehicle-handling stability under different emergency situations by the fundamental principle that adhesion coefficient between tire and road varies as wheel's slip. ABS emphasizes particularly on preventing wheel from locking during the braking process. ASR focuses on avoiding driven wheels' skidding to attain good directional stability and speedup capability through traction control in the course of vehicle acceleration or startup. Whereas,VDSC operates on physical limits of large vehicle slip angle and lateral acceleration,and enhances vehicle lateral stability by utilizing the additional yaw moment produced by different adhesion forces acted on the right and left side wheels. This dissertation works for the research on the following several aspects:vehicle dynamics system simulation (include modeling and computation);ABS,ASR and VDSC systems' control structure and nonlinear control schemes' selection and application;the discussion of some key technical issues involving in the development of ECU (Electrical Control Unit) in ABS;the verification of controller developed and fuzzy logic control software based on serial port communication between PC (Personal Computer) and 16-bit Single Chip Micyoco 80C196KC as well as real-time hardware- in-the-loop simulation technologies.Main works of this dissertation includes following seven aspects: Summarization of the evolution history,crux in realization and future outlook of ABS,ASR and VDSC. (2) Illustration of mathematics simulation methods for vehicle dynamics. (3) Presentation for advance variable-structure with sliding mode control (VSSMC) theories and their applications in the ABS based wheel slip control. Proposition of some improved fuzzy control algorithms and exploration of their implementation in the ABS based wheel slip control. (5) The study of ASR,comprising control means,objective,logic on-off control,simple fuzzy logic control (FLC) and VSSMC. The designations for VDSC system framework,fulfillment and variable structure with terminal sliding mode control. The development of ABS controller and experiment simulation.Detailed research contents and contributions of this dissertation are described as follow:(1) Three kinds of mathematics simulation ways for vehicle dynamics are illustrated,tire models in vehicle dynamics analysis are summed up and compared. Modeling process of whole-vehicle having seventeen degrees of freedom (DOF) is analyzed,the software VDPCSP (Vehicle Dynamics Performance Computer Simulation Program) is developed. Double-axis vehicle model holding ten DOF has been put forword by employing the Boltmann -Hamel approach,this model can be used to analyze the handling stability of open-loop or closed-loop braking vehicle,especially useful in examining the influence of ABS on vehicle cornered and braked,or in the research of VDSC.(2) An adaptive VSSMC is presented for second order nonlinear systems with system parameter uncertainties. Drawback occurred in the classical VSSMC can be alleviated in the proposed control scheme because of importing the eliminating chatterer. According to the control strategy put forward above,corresponding controller for ABS is designed.Quarter braking vehicle model with four DOF (including vertical and longitudinal motions of body as wellas vertical and spin motions of wheel) is built considering the effects of wind resistance,longitudinal inertia forces,the vertical dynamics associated with...
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