Research On Development Of Automotive Steering By Wire Controller

Steering-by-wire which is incorporate with advanced electronic technology information technology and control theory is a kind of brand-new concept for the design of steering system. It eliminated the mechanical connection between the steering wheel and the tunring wheel and break away from limitation of tradition steering system to bring more design space for automotive steering. The stability and reliability of a SBW controller is a sticking point to study for the reason of transportantion of angle and force signal.The dissertation studied on the performance of SBW and design of system and analyzed the characteristic of SWB and gave some design methods which consists of system parameters match design, sensors match design, electromotor type match design and retardment match design. PWM was used to control elctromotor - front wheel steering motor, steering feeling motor, using the Fuzzy-PID control principle to the current.The dissertation tried to design Fuzzy-PID controller which combines the advantages of PID and fuzzy control and improves the dynamic control effect and robustness of system by adjusting the parameters of PID controller on line. The electric control unit of SBW which consists of logic control circuit module and power driver circuit module, which based on Philips's high-speed sigle chip microcontroller P87C591and P87LPC778 is developed. It can collect the signal of tutning wheel angle and current reply.The study designed collecting circuitry, driving circuitry and back-check circuitry by oneself. And the controller also have the function of auto diagnosis and automatic alarm.The rich resources of hard ware gives the support for later updateing.Based on thedevelopment of hardware, we used C languge to develop the control program, to collect the status of system by interruption and contrlol turning wheel electromotor real time. The experimental results show that the electric control unit can results shows that the electric control unit can realize all required functions with strong stabilition and have good performance.This dissertatin lay the foundation for further research in steering-by-wire system .