Circuit Simulation And Controller Development Of Intelligent Driving Assistance System Based On STM32 Processor

With the rapid development of economy and the substantial increase of car ownership,the development of control technology,network communication technology and sensor technology has promoted the development of intelligent vehicle technology to a certain extent.Intelligent driving assistance system is the most critical technology for intelligent vehicles,which has attracted great attention from all walks of life.Lane keeping assist system(LKAS)and lane change assist system(LCAS)as the two important branches of this system,the importance is self-evident.The quality of track tracking in lane keeping and lane changing is an important criterion to evaluate the control effect.This paper focuses on the design and research of LKAS and LCAS path tracking.First,lane keep path following more than traditionally used PID control algorithm,in order to achieve better control effect,this chapter firstly introduces the theory of traditional PID control,fuzzy control and fuzzy PID control;then introduces the design idea of lane keep,control logic model,on the basis of the lane keep advance at PID driver model joined fuzzy control and formed the fuzzy PID pilot model to design the lane keep controller,through the lane keep vehicle parameters and the research of practical driving experience,the input and output parameters,theory domain,membership function and fuzzy control rules of the fuzzy controller are set up.Finally,Simulink model of lane keeping controller is built.A lane change controller is designed based on the fact when an emergency occurs,the vehicle may be too close and the braking distance is too short to the vehicle in front,resulting in the rear-end collision.Firstly,the constraint conditions of obstacle avoidance trajectory were studied,and the ideal trajectory of lane change was obtained by using the method of generating obstacle avoidance trajectory with the superposition of Constant velocity offset trajectory and sine function,and according to the actual driving environment information of the vehicle,two conditions are given to obtain the actual running track suitable for the active lane change of the vehicle.Secondly,track tracking adopts the fuzzy PID method of lane keeping.Finaly,the lane change fuzzy controller is designed and the Simulink model of the lane change controller is built.Control algorithm based on the above,designed the control circuit hardware system based on STM32 processor.the main circuit module include the voltage transformation module,motor drive module,CAN signal module,processor peripheral circuit module and burn file download module,use the circuit software.PCB diagrams made with circuit design software Altium Designer were sent to the processing plant to be processed into model experimental control circuit boards,which provided the hardware basis for the realization of the above control algorithms.Lane keeping and lane change are simulated and model experiment.First of all,the Carsim vehicle dynamics model was set,Co-simulation was carried out with Simulink model of lane keeping and lane change and Carsim vehicle dynamics simulation software,the results of which show that lane keeping and lane change controllers can perform their functions well on the basis of ensuring the longitudinal and lateral stability of vehicles.Secondly,the reliability of the control algorithm is verified by the experiments of model car controlled by single chip microcomputer for lane keeping and lane changing.