Analysis on the influence of friction coefficient on the starting control of automatic mechanical transmission

Based on the fact that friction coefficient changes with the friction surface temperature, the influence of friction coefficient on automatic mechanical transmission (AMT) is studied during repeated starting process. A model is established for the transmitted torque of clutch and the temperature rise on clutch plate surface during AMT starting. Based on the launching control rule of "fast-slow-fast", the repeated starting for AMT and the friction work of the friction pair are simulated. The simulation results show that friction coefficient changes with the change of the friction work. After several starting, friction coefficient and the transmitted torque of clutch diminish a lot, and the slipping between drive plate and clutch plate always exist, therefore, the vehicle can't start.