Research On Clutch Engagement And Simulation Of Automotive Mechanical Transmission

Due to its advantages of simple structure, high transmission efficiency, low cost, good manufacturing succession, etc., Automated Mechanical Transmission (AMT) holds an important place in the automatic transmission family, Vehicles can automatically gearshift with the help of automatic transmission, which can reduce driving fatigue, improve vehicle dynamic quality, fuel economy and reducing emission also. Automatic mechanical transmission AMT) is a type of high and new technology products that adepts to the situation of China nowadays. And it has a wide development prospects.Automated Mechanical Transmission (AMT) is rebuilded with the traditional dry clutch and manual gear transmission, the major change is the manipulation of the manual transmission, which is using the electronic control to achieve start and automatic transmission without changing in MT. The clutch engagement control is one of the most important problems of the power train automatic manipulation of AMT system, so this paper is mostly research on clutch engagement during vehicle start.Vehicle usually runs under the non-stable condition, therefore, to get the method of controlling clutch joint, a match between engine and transmission must be taken into account and a precise description for engine dynamic torque characteristics is required. In this paper, engine stable test data of a certain car were revised and fitted to build dynamic torque models.The paper probes into the issue of vehicle dynamics in clutch engagement process. It makes an analysis of friction torque transmission, the affecting factor of friction torque, impact degree and service life of clutch. Through the analysis of all kinds of control methods, the paper used speed-control method to design the controller. The control strategy contained two steps:the first is to judge the driver's intention; the second is to determine the engaging speed according to both driver's intention and rotate speed of engine and driven disk of clutch. At last, according to the control strategy, this paper designed the control law with fuzzy control.For the purpose of control method evaluation, simulation models of vehicle start was established using MATLAB/SIMUKLINK. Emulate base on different start intention and gradient, and compare the result. The simulation result shows that the fuzzy control strategy can reflect driver's start intention exactly, achieve clutch joint quickly and placidly.