Duality Between Incremental Nonlinear Dynamic Inversion and Transformation-Based Quasi-Linear Parameter-Varying Control

This paper presents a transformation-based robust nonlinear control design framework based on the concepts of Incremental Nonlinear Dynamic Inversion (INDI) and quasi-Linear Parameter-Varying (q-LPV) control. The duality between these popular control design paradigms is investigated. Control-oriented q-LPV model representations of (I)NDI-based closed-loop systems are presented for various inversion strategies, which creates a basis for robust synthesis and analysis of (I)NDI-based designs in the LPV sense. This includes extensions to singular perturbations that limit exact inversion in reality. The presented approach is demonstrated in a design case study for a nonlinear aeroservoelastic system, where INDI-based controllers are synthesized and quantitatively compared with direct q-LPV control based on linear fractional transformations.