Abstract: For a generic hypersonic vehicle with unstable longitudinal and lateral-directional mode, considering the three dimensional turbulence and their gradient, all states linear dynamic equations were established. All states H_∞ feedback control was proposed based on the discrete Kalman filter when three dimensional turbulence and system measurement noise were taken into consideration. In this way, state estimation created by the Kalman filter to the H_∞ controller was delivered. This method could guarantee the robustness when external atmospheric turbulence and itself parameter matrices perturbation caused by the flight condition variation existed. The results show that for both the nominal system and the perturbed system, H_∞ feedback controller based on the discrete Kalman filter can restrain external disturbance and system parameter matrices perturbation effectively. So the system owns strong robustness.

Key words: three dimensional turbulence, hypersonic vehicle, H_∞ control, Kalman filter, robustness