Contouring Control of Non-Minimum Phase XY Table System Using Trajectory ZPETC

Abstract- Non-minimum phase NMP model is a discrete-time model obtained from small or reducing sampling-time of open-loop input and output experimental data. The classical feed-forward controller design of this model using inverse of the closed-loop transfer function would produce an unstable tracking control. This is due to phase and gain errors that caused by NMP zero. Thus zero phase error tracking controller ZPETC strategy was introduced to encounter this NMP zero problem. Simulation and real-time controls on NMP XY Table system shows that the overall tracking performance for circular contour is significantly improved.