Sliding Mode Adaptive PID Control of an Automotive Clutch-By-Wire Actuator

Dry clutch control is one of the main components of both conventional and advanced automotive powertrain systems. In this paper, a robust control strategy is proposed which is suitable for the precise and accurate control of a clutch-by-wire actuator in automotive applications. A parallel connection of a sliding mode controller to a proportional integral derivative (PID) controller collectively forms the proposed robust controller. The sliding mode controller alone ensures robust control against system nonlinearities by providing a high feedback gain, but it also induces a control chattering phenomenon which could be harmful for the clutch-by-wire actuator. Instead of viewing chattering as an undesirable yet inevitable feature, the chattering signals are used as natural excitation signals for identifying an equivalent PID controller using the recursive least squares algorithm. Analysis is provided on the robustness properties of the control scheme. Simulation results of the proposed controller for a clutch-by-wire actuator are presented using a highly realistic clutch-by-wire system mathematical model. The simulation results demonstrate that the proposed control approach has achieved excellent performance indices while at the same time damp the chattering signal commonly encountered in sliding mode techniques.