Study On The Dry Clutch Engagement Lurch During Starting Phase

Automated Mechanical Transmission (AMT) is rebuilt with the dry clutch andthe traditional manual gear transmission. Due to its advantages of simple structure,high transmission efficiency, low cost. AMT has a broad market prospect. Because thedry cluth may be produce slipping lurch and synchronization lurch, Influence thestability of the AMT car during the engagement. Starting control of the clutch is oneof the key issues to be resolved in the process of developing the electronic system ofthe AMT. This paper is mainly study on the impact about the slipping lurch andsynchronization lurch to the vehicle starting stability during the dry clutchengagement. The clutch starting lurch control strategy based on torque coordinationwas proposed. The clutch starting control tests were made. Mainly contents include:1、Established transmission system dynamic model of the AMT, the reason ofthe slipping lurch and the synchronization lurch exist and the relationship betweenthem were analyzed. Focused on studying the impact on engine torque, frictiontorque and the load torque to the slipping lurch and the synchronization lurch.Established the system simulation model through the Matlab/Simulink. Analyzed thesize of the jerk and friction work at different starting conditions. Theoretical andexperimental results show that the amplitude of slipping lurch depends on the size offriction torque rate; the amplitude of synchronization lurch depends on therelationship between the friction torque and engine torque, load torque beforesynchronization instant; when the friction torque rate was increased, the slippinglurch would be increased positively, and the synchronization lurch would be increasednegatively.2、Position PID+adjusting velocity controller was used to track the clutchposition, in order to control the friction torque accurately during clutch engagement.It can provide technical basis to control the dry clutch engagement lurch based ontorque coordination during the starting phase.3、In this paper, the control strategy based on the torque coordination wasproposed to control dry clutch starting lurch. The starting tests have been done on theAMT experiment bench through this strategy. According to comparative analyzed theexperimental results, when the clutch engagement process is slow, the friction torquerate is small, the amplitude of slipping lurch is small, compared with the engine torque and the load torque, when the friction torque before synchronization instant istoo large, the amplitude of synchronization lurch is big; when the clutch engagementprocess is fast, the friction torque rate is big, the amplitude of slipping lurch is big,because of increasing the engine torque which coordinated engine torque, frictiontorque and the load torque before synchronization, the amplitude of synchronizationlurch is reduced. According to the size of the engine torque and the load torque tocoordinate friction torque which can realize to control slipping lurch andsynchronization lurch during starting phase, and it can control the size of frictionwork in a certain range.