Synthesis of attitude control for statically unstable hypersonic vehicle with low-frequency aero-servo-elastic effect

In this paper, an integrated attitude control scheme is proposed for a statically unstable hypersonic vehicle (HSV) with low-frequency aero-servo-elastic effect. Linear active disturbance rejection control (LADRC) is designed for the pitch angle to address the strong uncertainties and coupling effects. For the particular aero-servo-elastic effect with low frequency, a hybrid phase and gain stabilization technique is embedded into the LADRC framework to suppress the structural modes, which can reduce the phase loss around the crossover frequency. To achieve satisfactory tracking performance and robustness, a non-smooth H∞ optimization approach is applied to tune the controller gains, which simplifies the tuning and gain scheduling process. Monte Carlo simulation results demonstrate the effectiveness of the proposed control scheme.