Fault Diagnosis Of Automatic Transmission Control System Based On AUTOSAR

With the continuous development of the automotive industry,China’s automotive industry has gradually become an important source of the economy.Automatic transmission,as an important component of automotive power-train,plays an important role in car.Therefore,the stable operation of the AT is directly related to the safety of the car,and even has a major impact on the personal safety of drivers,passengers and pedestrians.Fault diagnosis of AT control system is an important part of vehicle safety.It is of great significance to study the fault diagnosis method of its control system.The automatic transmission works in a three-in-one way:machine,electricity,and liquid.The electronic control unit obtains the working status of each part of the automatic transmission and transmits the decision instruction to make the hydraulic system pushing the mechanical actuator to transmit power.If the electronic control system occurs failure will directly affect the operation of the entire automatic transmission.After analyzing the structures and mechanism of automatic transmission control system,studying the current AUTOSAR fault diagnosis technology,taking Aisin’s 6-speed automatic transmission(A760E)is took as its research vehicle.When deciding to use the NXP’s MPC5744P development board as the TCU electronic control unit of AT,and the main operating hardware and software modules are designed.AUTOSAR is the fault diagnosis platform of automatic transmission control system.Data about working status and fault condition of AT is transmitted through CAN bus.The fault diagnosis scheme of AT control system based on AUTOSAR is designed.Then,the RBF neural network fault diagnosis model and the support vector machine fault diagnosis model are combined with the D-S evidence theory fault diagnosis model respectively.After comparing the two cases,the combination of SVM and D-S is selected to diagnose the fault of automatic transmission control system.Taking the fault of speed sensor on input shaft sensor as an example,the hardware-in-the-loop technique is used to inject the fault status to the AT control system to test the feasibility of the diagnostic model.After testing,the fault diagnosis results of the automatic transmission control system based on the AUTOSAR fault diagnosis platform are consistent with the theoretical analysis.Fault diagnosis based on AUTOSAR can effectively diagnose the failure of the AT automatic transmission control system.AUTOSAR fault diagnosis technology combined with the fault diagnosis model of support vector machine and D-S evidence theory achieves the requirements of fast response,stable information transmission,and high rate fault recognition.It solves the problem of fault diagnosis of AT control system and improves the safety of vehicle driving.It has a certain engineering application and theoretical research value.