Abstract:

A power train dynamics model was built for an automatic manual transmission (AMT) vehicle
to realize the transmitting torque direct control of the automatic clutch. The discrete state space model for
estimating the clutch transmitting torque was derived. The state vector was constituted by the engine rotation
speed and the clutch transmitting torque. The Kalman filtering algorithm was used to estimate the clutch
transmitting torque, to estimate clutch transmitting torque for vehicle starting process, and to analyze estimation
errors by comparing the estimated and simulated values of the clutch torque. Impact of the sample time (5-25 ms)
on clutch torque estimation errors was explored. The results show that the torque estimation error increases
with the increase of sampling time; the lower limit of torque estimation accuracy is 7.5% at sampling time 10 ms.
Therefore, the algorithm show sufficient accuracy.

Key words: vehicles, automatic manual transmission (AMT), automatic clutch, transmitting torque, Kalman filter