Study On Low Speed Driving Cruise Control Of Urban Traffic

The automobile low speed cruise control system is the latest application technology for low-speed travel(especially in traffic jams),which is based on cruise control systems and adaptive cruise control systems.Along with the development of the economy,the number of cars in China is growing fast,which not only brings many conveniences,but also leads to road traffic congestion,traffic accidents a,travel difficulties and many other negative effects.Therefore,people are eager to alleviate driving fatigue,improve vehicle safety and improve ride comfort when they are riding.At this time adaptive cruise control system(ACC)came into being.However,at present,the ACC is mainly applied to the highway driving conditions with the speed higher than 40km/h,but not to the low-speed operating conditions such as urban roads.Therefore,it is necessary to carry out in-depth study on vehicle cruise control under urban road conditions.This paper mainly studies the low-speed cruise control system in urban conditions,especially for the three core parts of the cruise control system: safety vehicle distance,control algorithm and vehicle longitudinal dynamic model.Firstly,the complex vehicle system is simplified,including the engine model,the automatic transmission model,the torque converter model and the vehicle body model,and the model is connected to verify it,which ensures the rationality of the model.Secondly,based on the workshop time and distance model,a safe distance for low speed cruise is established to ensure the safety of traffic and the high utilization of roads.This is the most basic part of cruise control.Then,based on the control strategy of fuzzy control,a fuzzy logic controller with output deviation,distance throttle opening or brake pedal stroke is designed,and the fuzzy controller is based on the Simulink platform achieve.Finally,we mainly simulate the typical operating conditions under the urban road,and give the simulation results and analysis.The MATLAB/Simulink simulation results show that the transmission system model and control strategy model can be very good for vehicle starting,tracking,acceleration and braking process in complex conditions.Therefore,it can effectively ensure the automatic adjustment of the vehicle speed and the safety of the drivers.