Practical output tracking control for nonlinearly parameterized longitudinal dynamics of air vehicles

Abstract

This paper studies a practical output tracking control problem of the nonlinearly parametrized longitudinal dynamics of air vehicles. To make output tracking errors within an arbitrarily prescribed bound, a practical output control scheme is developed, employing a new integrated framework of a functional bounding technique for handling nonlinearly parametrized dynamics and a nonlinear state-feedback controller structure for regulating the multi-output tracking errors. A coordinate transformation and a control input domination design are used to decouple the air vehicle system into the attitude subsystem and velocity subsystem. The proposed control scheme achieves the closed-loop signals global boundedness and practical output tracking properties, despite the unknown parameters appearing in aerodynamic forces and moments nonlinearly. An air vehicle under additional disturbances is also studied for enhancing the robustness of the proposed controllers. Simulation results on a vehicle model that is affected by the structural flexibility illustrate the effectiveness and robustness of the practical output tracking control scheme.