Identification of the Precision Moving Stage Based on Degeneration Input

Because the non-smooth nonlinear dead-zone exists in the precision moving stage, both its tracking accuracy and sensitivity are severely deteriorated. In this paper, a sandwich model with dead-zone is employed to decribe the precision stage. In this case, a two-stage identification scheme is presented to model the sandwich model, which a special signal called the degeneration input is first designed to degenerate the non-smooth nonlinear dead-zone into a static linear function and the Recursive General Identification Algorithm (RGIA) is used to estimate its parameters. Finally, a numerical simulation and the experimental results are presented to illustrate the performance of the proposed identification.