Hypersonic vehicles (HSVs) have become one research focus within the current aerospace community for their significant potential in both military and civil applications. As a key subsystem of HSVs, flight control system is an important guarantee of achieving safe flight and fulfilling complex task. However, due to the special integrated airframe-propulsion system configuration and complex variation of the flight condition, the dynamics of HSVs present unmanageable peculiarity, such as strong couplings, strong nonlinearity, significant uncertainties, and fast time-varying conditions. All of these pose a significant challenge for the controller design of such vehicles. Based on comprehensive analysis of HSV dynamic characteristic, several key problems of HSV controller design are deeply investigated in this dissertation, using the adaptive immersion and invariance (I&I) technique as the primary method. The main contributions are addressed as follows. (1) An overview of the common HSV models used in the literature is given. The dynamic characteristics of the waverider configuration HSVs are analyzed thoroughly and several vital problems for the design of control systems are summarized, which lays the foundation for the following controller design. (2) For the problem of parameter uncertainty and physical constraints on the actuators, an anti-saturation robust adaptive control scheme based on adaptive I&I is proposed for HSV. For this scheme, the longitudinal dynamics of HSV are first decomposed into velocity, altitude-flight path angle and angle of attack-pitch rate subsystems. Then adaptive I&I based controllers are designed for each subsystem. Constrained command filters are used in the design of parameter estimators, which avoid the magnitude and rate constraints on the actuators and intermediate states affecting the parameter adaptive update process. Simulation results show the effectiveness of the proposed scheme. (3) For the problem that certain states of HSVs are difficult to measure accurately in real time during the hypersonic flight, an output feedback control scheme based on adaptive I&I is proposed. For this scheme, an adaptive I&I based state observer is first designed, which is used to reconstruct the full states of the system through the on-line estimations of the unmeasurable states (flight path angle and angle of attack). Then the observer backstepping technique is used to construct the whole control architecture, while dynamic surface co...
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