Modeling of a dual actuator system and its control algorithm preventing saturation of fine actuator

This paper discusses the design of control structure of dual actuator system, which is considered as DISO system, for high precision manufacturing stage. It proposes that PA tracks error signal between estimated coarse position and output coarse position at control sample to prevent saturation. Estimators are designed for both fine and coarse actuator plants to derive input signal to PA and state-feedback gain is defined by LQR. Dynamic model is defined by Newton's second law and coupling dynamics is considered for control structure. Experimental results demonstrate that unnecessary movement of PA during the transient response is reduced resulting in enhanced overshoot and settling time of the DSA system.