Flatness-Based Adaptive Backstepping Control for Underactuated ACVs

This paper presents an effective trajectory tracking control strategy for an underactuated air-cushion vehicle (ACV). The differential flatness approach is applied to convert the strongly coupled nonlinear dynamics into a fully actuated equivalent system through appropriate selection of flat outputs, thus reducing the complexity of controller synthesis. On this basis, a backstepping control law is developed with recursive virtual controls and Lyapunov stability analysis to ensure asymptotic error convergence. Numerical simulations demonstrate that the proposed method achieves accurate tracking with fast convergence and robust performance.