Research And Design Of PEPS System By Model-based Design

The automobile,as an irreplaceable transportation in people's lives,has been proposed to have higher comfort and safety requirements.And PEPS(Passive Entry and Passive Start)system meets these requirements,which is gradually becoming a mainstream option in automotive keyless entry application.The driver,who does not operate the intelligent key,only needs to carry the key with him,and then he can achieve these functions of locking or unlocking the vehicle door and starting the engine.PEPS system has the advantages of comfort and safety,which makes it a lot of room for promotion.Based on the complex functions and safety technical requirements of the PEPS system,this thesis presents the model-based system development method.In the automotive electronics industry,this model-based development model has been gradually used.It has a graphical design concept to facilitate communication and maintenance,and it can automatically generate embedded code.This method has great efficiency and economy,which has a broad application prospects.In this thesis,the following research is focused on the system structure and function,model-based design flow,system bus simulation and test verification.(1)Based on the research of PEPS system,the structure and function of system are described in detail.Analyze these functions of passive entry,passive start,ESCL(Electrical Steering Colum Lock)control and warning and prompt,in order to provide the basis of control strategy for the realization of model-based design method.(2)Introduce the basic concept and process of the model-based design method,prepare the system requirements documents,use the Simulink/Stateflow to model the controller of the PEPS system hierarchically,and design and implement the specific logic of the function through graphic language.And in the development process,complete model checking,model validation,fixed-point design and SIL(Software-in-the-loop)testing.Through the code optimization configuration,Embedded Coder tool is used to automatically generate embedded code and related code reports for model and code consistency checks.(3)Design and study the work process of CAN bus of PEPS system,build the whole network simulation environment of the system based on CANoe bus test tool,and then realize the monitoring and analysis of system bus.In order to achieve the system bus network simulation,design the CAN bus database,establish the system interactive panel,build the system simulation topology structure,and write the node CAPL language simulation program.With the graphical form,the situation of signal communication is reflected to observe and analyze simulation results.(4)In order to verify the code accuracy of the generated algorithm,it is integrated with the driver code,and the integrated code is compiled and downloaded to the MC9S12XS128 development board.Development board and the bus testing tool need to implement CAN bus communication so as to test the correctness and reliability of the code to realize system functions.The test ensures consistency of code and functions to meet the design requirements.