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In the light of the broad range of hypersonic flight conditions, a design method of switching control based on guardian maps is proposed to guarantee the global stability within the flight envelope. First, a linear parameter varying (LPV) model of a hypersonic vehicle is established over a range of hypersonic flight conditions. The parameters of controller are determined by pole placement technology with the target pole locations at the boundaries of the parameters variation range. Second, a new range of flight conditions that ensures system stability with current controller is analyzed based on guardian maps. The execution of the iterative process is used to determinate the set of controller parameters overall the flight envelope with initial target pole locations. By switching controller parameters the closed-loop performance is guaranteed over the entire flight envelope. The simulation shows that the proposed design method has the ability to ensure the global stability over the flight envelope, and achieving good tracking performance.

Compared with traditional vehicles, the dynamic model of hypersonic vehicles features higher nonlinearity, tighter coupling and stronger uncertainty. What's more, the designed controller needs to have more stringent performance demands as well as robustness requirements. According to the guardian maps theory, a proposed design method can adaptively adjust control parameters in relation to the given control structure for hypersonic vehicles. First, a linear parameter varying (LPV) model of a hypersonic vehicle is established, and after that handling qualities are translated in terms of eigenvalue confinement. Then for a fixed controller architecture and initial controller gains, a set of control parameters is adjusted automatically using this theory while ensuring generalized stability in the expected flight process. Finally, an example of a hypersonic vehicle is provided in simulation to verify the feasibility of the proposed control method.