AMT Control Method In Vehicle Starting And Shift Process

Automated mechanical transmission (AMT) not only has the function of automatictransmission, but also has the advantages of high transmission efficiency, simple structureand low cost, which has broad prospects for development. Clutch automatic control duringvehicle starting is one of the difficulties of AMT technology, and directly affects ridingcomfort and service life of the clutch. And shift rule, as one of the cores of AMTtechnology, has great impact on power performance and fuel economy of the vehicle.Aiming at how to improve starting performance and give full play to the powerperformance of the vehicle, the main content of this paper include:Firstly, the working principle of AMT, characteristics of engine and diaphragm springclutch, clutch engagement process and the vehicle starting process are analyzed. Then themodels of engine, diaphragm spring clutch and clutch engagement are established byusing simulink software, which lays the foundation for the research of clutch engagementcontrol in vehicle starting and making shift rule in shift process.Secondly, the evaluation indexes of vehicle starting process are analyzed and clutchmaximum engagement speed under the constraint conditions of jerk is obtained. Fuzzycontrol algorithm of clutch engagement with engine running at local constant speed isproposed, aiming at the AMT system established model difficultly and mutualcontradiction of the evaluation indexes. Simulation results show that this algorithm caneffectively reduce friction work under the constraint conditions of jerk, which willimprove starting performance of the vehicle.Thirdly, this paper analyzes dynamics equations of the vehicles and the relationship ofspeed, acceleration and throttle opening is gained. For how to better play to the powerperformance of the vehicle, the best dynamic shift rule is made with speed and throttleopening as arguments and the feasibility of shift rule is verified by simulink softwaresimulation.