Feedforward control of LTI system with uncertainty and disturbance

This paper presents a control scheme for a linear time invariant (LTI) system with uncertainty and disturbance, which are not assumed to be matched with the control input. The presented control scheme consists of a stabilizing feedback controller and a newly developed feed forward mechanism, which counteracts the uncertainty and disturbance through the reference path. In contrast to the related control methods, such as time delay control (TDC) and uncertainty and disturbance estimation (UDE) based control, the scheme presented in this paper does not impose any structural constraints on the controlled plant. The presented control scheme was verified experimentally using a flexible mechanical testbed with a poorly damped resonance.