| With the continuous development of automobile industry, people have more and more requirements of the performances of car including comfort, energy efficiency, safety and environment. ACS (Automatic Cluth System) which meets these high performances is developed rapidly and used widely. Automatic is a kind of power transmission equipment which can clutch automatically based on the clutch manual gearbox and cancells the clutch pedal. It conforms to functional and affordable product development trends.it makes driving more simple and convenient, faster acceleration in start and shifting. Furthermore it is low cost and easy maintenance. Aiming at the characteristics of micro-cars and experimenting based on N1 type of General Motor Corporation, the automatic clutch system is studied and implemented in this paper. Main reseach work and innovation are as follows.(1) Research on dynamics and the tribology performance of clutch. The clutch parameter calibration and design system is studied and completed. A method of using computer-aided design to complete design and simulation of clutch is proposed. Parameters can be judged after adjustment to obtain the most reasonable parameters of the clutch.The adjustmen will not stop until the clutch diaphragm spring and control agencies meet the requirements.Aiming at clutch shakes of starting, the experiment that sliding speed of cluth brings impact to friction and wear is studied. Automatic clutch is brought to control the speed in starting process.(2) The overall control strategy based on multi-mode control mode of clutch binding process is proposed. A multi-mode control way "proportion-fuzzy-PID"is adopted in order to realize the clutch "fast-slow-speed" of the engagement rule in this paper. In no-load sliding stage, proportional control meets its swiftness; in slipping work stage, fuzzy control improves the anti-damping characteristics; and in synchronicity stage, PID control can solve steady precision problem. Simulation shows that the multi-mode control can play its'advantages of each control mode respectively and has a better control effect than any other single control.(3) The speed control problem of executive equipment control system is studied. Good control strategy can achieve good operating results or not, another key issue is control of the implementing agencies. The dual-loop control system is adopted. The traditional PID control algorithm is used to control current and fuzzy-adaptive PID control algorithm is used to control displacement. Simulations and experiments show that it can track position accurately and it has good dynamic and static performance. In addition, it is strong robustness of adapting to changes in system parameters and improves respond speed. The control system of executive equipment can meet the requirements of clutch engagement.(4) The control system of automatic clutch is designed and realized. Aiming at the N1 model of micro car, various modules of the hardware circuit and interface circuit and software are designed and implemented at the core of ATmegal6 microcontroller with high-performance. According to characteristics of electronic control unit of the micro-car, the communication protocols of K line is studied and the application programme is developed.some signals that is adopted by hardware sensors before is now read from ECU by K line communication. it simplifies the system greatly and improves reliability.(5) Bench test and loading test of the system is studied. Startup tests in operating conditions are made. Start conditions with the different degrees of throttle opening and the different slope are simulated by bench test. The collecting data of bench test and fitting curve show that the vehicle can start successfully and smoothy in various conditions.the whole starting process can fully reflect the intention of the driver and the engine speed fluctuation is small. The whole system has been installed in prototype car and operated for Period of time. The system runs well.
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