An Efficient Robust Servo Design for Non-Minimum Phase Discrete-Time Systems with Unknown Matched/Mismatched Input Disturbances

This paper presents an efficient proportional-plus-integral (PI) current-output observer-based linear quadratic discrete tracker (LQDT) design methodology for the non-minimum-phase (NMP) discrete-time system with equal input and output number, for which the minimalized dynamic system contains the unmeasurable system state and unknown external matched/mismatched input disturbances. Illustrative examples are given to demonstrate the effectiveness of the proposed approach.