Friction Coefficient, Torque Estimation and Indirect Smooth Shift Control Law for an Automatic Power Transmission 2000-05-0066
For shift quality improvement, torque sensors are currently too expensive to be used on production vehicles. To achieve smooth acceleration shift, the reference trajectory of the clutch slip speed for accomplishing the shift process within a designated shift completion time and its relationship with the clutch actuating torque were suggested by Jeong and Lee (13). In order to facilitate the proposed algorithm, nonlinear estimators for necessary information such as the axle shaft torque, clutch friction and turbine torque were designed using only speed sensors. Accounting for the modeling error, a control law for this indirect smooth shift was proposed based on the above mentioned suggestions. Simulation results of the proposed estimators and shift controller were presented and further considerations for practical applications are discussed.
Heon-Sul Jeong, Kyo-II Lee
1) School of Mechanical Engineering, Kunsan National University, Korea,
email@example.com 2) School of Mechanical & Aerospace Engineering, Seoul National University, Korea,
Seoul 2000 FISITA World Automotive Congress