Linear Parameter-Varying Control for a Hybrid Unmanned Aerial Vehicle

Abstract

In this paper, a linear parameter-varying (LPV) control law based on the parameter-dependent Lyapunov function (PDLF) is proposed for a dual-system hybrid unmanned aerial vehicle (UAV) in the fixed-wing and hover flight regimes. The hybrid UAV is a nonlinear, coupled, and multiple-input multiple-output system, which brings challenges to control law research. Compared with the conventional gain scheduling control method, the PDLF-based LPV control law not only guarantees a larger flight envelope of the UAV but also greatly improves the efficiency of the control law design process. Firstly, the nonlinear model of the hybrid UAV is briefly introduced. On the basis of the nonlinear model, the LPV model is built based on Jacobian linearization. Moreover, a cascade control structure is designed, including an inner loop and an outer loop. The inner-loop control law is further divided into longitudinal and lateral-directional controls and synthesized in a mixed-sensitivity-based two-degree-of-freedom control structure using the PDLF-based LPV control method. The proportional-integral-derivative control law is used to simplify the outer-loop control law design. Simulations are conducted to demonstrate the stability and performance of the proposed control law.