Disturbance observer-based attitude control for hypersonic vehicles with input constraint

In this paper, a robust attitude control strategy for hypersonic vehicles is proposed, which combines a disturbance observer and an anti-saturation method with the basic feedback linearization controller. First, the employed nominal model of hypersonic vehicles is transformed through feedback linearization method and stabilized by a basic controller. Then, a disturbance observer is proposed to generate the estimate of aerodynamic parameter uncertainties and complex disturbances on the vehicle model. Furthermore, an auxiliary system is established to reduce the impact of input constraints. The designed control method presents good attitude tracking ability and robustness. Finally, the effectiveness of the proposed technique is illustrated by several simulations.