Tracking controller with harmonic disturbance cancellation

In this paper we consider the tracking problem with simultaneous unknown harmonic disturbance rejection for a linear parametric uncertain stationary SISO systems of arbitrary relative degree. The proposed structure is an extension of authors' previous results, which are based on output controller “consecutive compensator”. Closed-loop system stability is proven and an iterative disturbance frequency estimation algorithm with ‘sliding window’ update scheme is introduced. Parallel kinematics Ball-and-Plate on a movable platform robotic system is considered as a test-bed, while the non-prehensile ball manipulation along a predefined cyclic trajectory under bounded disturbances is a task to be solved.