Trajectory-adaptive digital tracking controllers for non-minimum phase systems without factorisation of zeros

摘要

The paper discusses the design of a zero phase error feedforward digital tracking algorithm. The proposed algorithm can be used for minimum or non-minimum phase systems without requiring the zeros polynomial to be factored into minimum and non-minimum phase factors. To improve tracking when the zeros are close to the unit circle, a scheme called trajectory- adaptive zero phase error control is proposed in which the controller parameters are automatically tuned online to the current reference trajectory without requiring explicit information on the function to be tracked.