Two novel robust tracking control strategies for eliminating aircraft wing rock

Nonlinearities are essential features in the model of aircraft wing rock system and limit cycle is a typical phenomenon when flying without any control force. In this work, we concentrate on two robust tracking control schemes for automatic flight control systems by using forwarding technique. Combining forwarding technique with adaptive control and disturbance observer, manifolds are represented as insensitivity to parameter uncertainties and external disturbances. A second-order filter is employed to compute mappings and their analytic derivatives at each step of the design. The global, uniform, and ultimate boundedness of all trajectories are guaranteed by internal stability of filters. Unlike some of the existing control methodologies, modularization and no differential operations together with reduction of computational load are the main advantages for practical applications. Scheme 1 requires no prior knowledge of unknown parameters and scheme 2 analyzes the convergence rate of uncertainty observers. Controller performance and comparison between two approaches are demonstrated via simulations