Integral-based robust LPV control of nonlinear flight systems

Abstract

This paper presents a novel speed control method for an unmanned flight system. A Polytopic Linear Parameter Varying model is generated by linearization of the nonlinear dynamic model around several trim points. As a novelty of this paper, an Integral action over the tracking error is added to a conventional state-feedback to form the proposed control law. Augmenting the proposed control action to the system dynamic, the proposed control law is reassigned as a common state-feedback control problem. An attenuation level for the tracking error under external disturbances is guaranteed by solving the related linear matrix inequalities to compute the control gains. In the end, the designed controller has been implemented for different scenarios in order to maintain the speed in different modes with the ability to control the longitudinal, Lateral, and altitude velocities simultaneously. The simulation results show the effectiveness of the proposed control against the system uncertainties, external disturbances, and the interactions between different channels.