The Design Of Cruise Control System

Along with the progressing of science and technology, the continuous development of auto industry and the highway have appeared as mushrooms after rain, people see the safety performance of the car and driving comfort as an import thing,The CCS has stepped into a stage of rapid development. Now the CCS is applied into many middle-standard cars. Although China’s CCS is not very mature when compared with abroad CCS, it actually has a good development prospect and research value.This thesis mainly through programming and the selection of control method to simulate the working process of CCS. in order to respect the working process more intuitive, this thesis builds a simulation experiment platform. In the control method of selecting, most domestic CCS adopt common PID control, this thesis combine the incremental PID algorithm and position type PID algorithm together on the basis of common PID control.It can adapt vehicle traveling condition.Firstly, this thesis briefly introduct the CCS history and the process of development. It also introducts the4common current classes of CCS.Then this thesis detailedly introduce the basic stucture and the working principle of CCS,It lays a good foundation of the next core content.Secondly, this thesis introducts the three commonly used of three control method of CCS. After a series of analysis and formula, this thesis combine the position type PID algorithm and the incremental PID algorithm together as the control method. First of all, the thesis list a Dynamic balance equation through a longitudinal force analysis of vehicle body and wheel.Secondly, using SIMULINK for car longitudinal dynamics and PID control to simulink and binding technology to combine this two sbusystem together and simplify. Finally debugging the PID three control parameters in SIMULINK module, after the simulitation we can find the system can get the response time of the fast, small overshoots, fully meet the requirements through the wave figure, It can reach the best control system.Finally, after introduce the hardeware of this thesis detaily,we use MC9S12XS128as the core of CCS, then discusses the procedure for the process in this thesis, using the development platform of programming software Codewarrior to the write the core program, and detailedly introduce the AD conversion module and PWM initialization, then using of hardware built a experimental platform used to debugging and verify the feasibility of the written procedures.