Adaptive disturbance estimation and robust control for bank-to-turn missiles autopilot design

An adaptive control scheme based on disturbance observer is proposed in this paper for the bank-to-turn missile autopilot design. In the past, the disturbance observer has been introduced for bank-to-turn missile system to improve system performance in the presence of severe disturbances. However, the disturbance rejection performance is not quite satisfying when considering the fluctuation of the aerodynamic parameters. Therefore, a kind of time-varying disturbance observer is proposed in this paper to enhance the robustness against variations of aerodynamic parameters. The main innovation is that the nominal model of the BTT missile in the disturbance observer is updated over time along with the aerodynamic parameters. And simulation comparisons in the last part show the effectiveness of the proposed adaptive control method.