Novel Unified Control Strategy for a Compound VTOL Vehicle

The highly nonlinear dynamics, overactuation, and model uncertainties pose significant challenges to the flight control of vertical take-off and landing vehicle. This paper designs a unified flight control strategy based on a cascaded incremental controller. The proposed unified control strategy consists of two loops of inner and outer incremental nonlinear dynamic inverse controllers to deal with the uncertainties in translational and rotational dynamics, where the optimal control allocation scheme based on weighted least squares deals with the actuator constraints and control priorities in the overactuation allocation. In addition, the nonlinear dynamic inverse is used for decoupling, linearisation and control for kinematic models where the nonlinear model is known. Simulation studies demonstrate the full-envelope control performance of the proposed control strategy.