Automated manual transmission fault diagnosis based on hybrid system characteristic

Automated manual transmission(AMT) fault diagnosis based on hybrid system characteristic is studied. The hybrid automata are used to build AMT automatic transmission system model and analysis is made on the consistent relationship between the behavior of trajectories and the hybrid system model. The fault definition of AMT automatic transmission system is analyzed and the fault behavior of AMT hybrid system is defined by the hybrid system model. The fault diagnosability of the hybrid system is studied based on the fault behavior of the AMT hybrid system. The relationship between fault, fault diagnosability, fault diagnostic accuracy and measurable system state variables is explained by the system trajectories and the concept of fault entropy is used to describe the degree of fault diagnosability. From the AMT system function, system model trajectories and control cycle perspective the behavior of AMT hybrid system is analyzed and classified to raise AMT automatic transmission system fault diagnosis strategy. The fault diagnosis strategy with the diagnostic algorithm is transplanted to the real car platform and a large number of vehicle mileage prove the strategy's correctness and real-time.