Ultimate boundedness control of unknown SISO plants with polynomial disturbances

A dynamic control scheme capable of rejecting polynomial disturbances in single input-single output (SISO) unknown plants is presented. The control signal is a nonlinear continuous function of the filtered input and output, and of their derivatives. The proposed controller guarantees the ultimate boundedness of the error between the plant output and that of a reference model; the design procedure also allows the designer to arbitrarily prescribe the rate of convergence of the tracking error.