Fictitious reference iterative tuning of non-minimum phase systems in the two-degree-of-freedom control architecture: A Laguerre expansion approach

In this paper, we consider the data-driven tuning method for a two-degree-of-freedom (2DOF) control architecture to achieve a desired tracking property for non-minimum phase systems. By utilizing the fictitious reference iterative tuning (FRIT), which enables us to obtain an appropriate parameter of a controller with only one-shot experimental data, we propose an effective tuning method of the feedforward controller approximated by the finite sum of the Laguerre expansion with tunable coefficients. We show that the proposed method also yields an estimation of unstable zeros of a plant with high accuracy. The proposed method is validated by illustrating numerical examples.