Observer-based adaptive dynamic sliding mode control for automatic clutch position tracking

The automatic clutch's precise and stable position tracking is critical in automated manual transmission, significantly influencing vehicle performance. Clutch position control is challenging due to directly unmeasurable clutch output position, nonlinear characteristics, parameter uncertainties, and external disturbance of the automatic clutch system. This paper proposes an observer-based adaptive dynamic sliding mode control strategy to overcome these obstacles to the clutch position tracking process. The extended state observer (ESO) introduced in the designed strategy handles total disturbance, including nonlinearities and uncertainties for feedback control and total compensation. A sigmoid tracking differentiator arranges the transient process and smooth approach signal for the reference input and its differential signal. An adaptive dynamic sliding mode controller acts as the primary feedback control to realize fast and precise position tracking of the automatic clutch system based on the signal from ESO. Simulation and hardware-in-loop (HIL) experimental tests verify the effectiveness and advantage of the proposed control strategy for the clutch position tracking performance in the face of parameter perturbation and external disturbance, for example, the root mean square value of static tracking error of the designed strategy is 14.9% and 24.7% lower than that of ESO-based sliding mode control and robust sliding mode control strategy in the HIL test, respectively.