Abstract: To solve the problems of velocity fluctuation and overheat of friction pair during creep, an analysis on friction characteristics of dry friction pair is conducted and the heat safety boundary is determined. A dynamic powertrain system model is established, and a start control strategy is obtained which meets the jerk requirement and have small velocity overshoot compared with target velocity 3km/h by considering variation of friction coefficient when vehicle is starting and in process of creep. Taking the minimum deviation between the actual speed and the target speed as the control objective, the clutch compression force is adjusted by PID to keep the vehicle speed stable during creeping, and the creeping control strategy is formulated to ensure thermo-safety of clutch in creep

Key words: vehicle transmission, creep, start, control strategy