Design And Implement Of A Model-base Developmented Controller For Start Vehicle Without Key

Keyless start system is also called PEPS (Passive Entry and Passive start) system, whichcould let the user unlock/lock vehicle doors or start engine without the diver operating theintelligent key. When the driver with something in hand is not able to operate the key toremote unlock the vehicle, PEPS system provide more convenience to the driver, when thedriver is near to the vehicle, PEPS system could unlock the vehicle automactilly, then thediver entry the vehicle, he/she press the engine Start/Stop swith to start the vehile, the process(entry and start vehicle is not need the diver operate the kay anymore. When the driver leavethe vehile, PEPS system doesn’t need the driver operate the kay to lock vehicle anymore,PEPS system will lock the vehicle automactilly when the driver go away far from his/hervehicle. That can avoid the risk of lost the driver property due to the driver ‘s forgetting oflocking vehicle when he/she leave away.The application of PEPS system radio frequency identification technology query the usercarries a smart key is authorized and the intelligent key position, in order to achieveautomatic vehicle solution, atresia and keyless start. Vehicle within the complexelectromagnetic environment, the vehicle shape and electrical parts layout also differ inthousands of ways, all these will lead to the key position error judgment (i.e. when the userleaves the vehicle and intelligent key in the car, the PEPS system wrongly judged intelligentkey on the outside of the car will be the vehicle to automatically lock causes the user to enteror the driver is still outside the car, PEPS system error judgment to the intelligent key in thecar, another keyless vehicle occupant will be false start), how a certain error range accurate identification of smart key position is the realization of PEPS system function key. At thesame time in the smart start process in addition to verifying the key position and legitimacy,the PEPS controller for electronic steering ESCL and vehicle power distribution, in theprocess of driving vehicle if PEPS controller failure caused the electronic steering columnlock causes the steering wheel cannot rotate or power failure caused by vehicle led to theengine cut out, all of these will lead to the personal safety of users in danger, so safety designin the PEPS controller development is particularly important.According to the PEPS controller of the complex functional and safety designrequirements, the paper put forward a model based on the development of PEPS controllermethod, through the Matlab statflow of PEPS controller using logic modeling, complexfunction layer and in the model design specific logic, using the graphical language logic,based on the field intensity calibration and vehicle using the model to determine theintelligent key position method, the realization of the smart key position accuracy ofrecognition, and intelligent key position of the judge and the realization of specific functionsto separate design, improved PEPS controller for different models adaptability. And throughthe dual MCU control design for the electronic steering ESCL, vehicle power distributioninvolving personal safety function, improve safety performance.The paper mainly carried out the following work:(1) Based on the PEPS controller as theresearch object, first analyzes and studies the PEPS system from which components in thevehicle, how to work, to study PEPS controller in the system is responsible for the function,how and in other parts of coordination work to achieve functional.(2) In a comprehensiveanalysis of the PEPS controller functions and features, the complicated function and safetydesign requirements, a method based on model of the development process, by using modelPEPS controller all logic, the graphical language will break up the whole into parts withcomplex function, classification of model design and implementation. And the dual MCU(MC9S12ET256, STM8AF6166) design, mutual check complete electronic steering ESCL,vehicle power distribution control, meet the safety performance requirements.(3) Proposed avehicle field intensity calibration method, using model to implement the intelligent keylocation judgments, with its specific function of the realization of separate design, improvedPEPS controller for different PEPS system adaptability (4) At the end, the PEPS systemtesting and validation, test results show that the PEPS controller to meet the requirement ofthe system, realization all of the features of the work, proved the correctness and practicalvalue.