Research On The Fuzzy Control And Simulation Of Automobile Cruise System Based On The City Traffic

With the rapid development of social economy, the vehicle holdings is growing rapidly in China, which brings lots of convenience to people, meanwhile, also leads to traffic congestion, the rise of the traffic accident rate as well as travel difficulties and many other negative effects. Therefore, there is an urgent need to improve the safety of automobile and the comfort of automobile. Adaptive Cruise Control system of automobile can reduce the strength of driver’s fatigue, and improve the active safety of automobile. But the present research about ACC is mainly used in the condition of the speed higher than 40km/h, which is not suitable for the situation of urban road at low speed operation, so research the ACC of city traffic is necessary.In this paper, research and simulate fuzzy cruise control method based on the working condition of city. It mainly divided into five parts. The first part introduces research background and significance of ACC, also research status at home and abroad. The second part studies the method of control fuzzy cruise control of automobile based on the city traffic condition. At first, establish the modeling of vehicle’ longitudinal dynamics system, mainly including the model of engine, hydraulic torque converter and automatic transmission, vehicle transmission, running system, vehicle movement system as well as the model of brake system. Secondly, design controller in method of fuzzy, which set relative distance and relative speed deviation as input and use throttle percentage and brake pedal stroke as output, automatically adjust the throttle percentage or the brake pedal. Finally, research the method of cruise control based on the PID control theory under the condition of higher and lower speed. The third part mainly simulates the automobile fuzzy cruise control on the condition of city traffic by using the MATLAB/Simulink. First of all, urban road car under fuzzy cruise control mode is classified: follow the preview vehicle at low speed, following the vehicle which cut into, automatic start and automatic parking, preview vehicle acceleration-deceleration until stop-start acceleration. Second, establish the simulation model of the vehicle’ longitudinal dynamics system, and then realize the function of simulation of automobile fuzzy cruise control system. The fourth part gives the simulation results mainly aimed at operation condition of fuzzy cruise control under the condition of city traffic and analyze the results. The simulation result shows that the fuzzy cruise control method can automatically adjust the speed of the cruise vehicle. The fifth part summarizes main research result and the content needed further studied.The research conclusion can provide necessary theoretical reference for researching the control method of automotive active safety and the development of ACC.