Adaptive Attitude Control for Spinning Projectiles with Time-Varying Aerodynamic Uncertainties

Most gun-launched guided projectiles adopt a spinning airframe to simplify the control structure and improve stability. However, the cross-coupling effects of inertia, aerodynamics, and control caused by spinning increase the difficulty of the autopilot design. This paper proposes an adaptive attitude autopilot design method for a class of spinning projectiles with time-varying aerodynamic uncertainties. First, a fully actuated attitude dynamic model of the pitch/yaw channel for a spinning projectile is established, in which the aerodynamic force/moment are regarded as time-varying uncertainties. Second, an adaptive attitude autopilot is proposed by combining fully actuated system theory and adaptive control theory to restore the linear characteristics of the closed-loop system. Then, a parameter-safe adaptive law is presented using control barrier functions to ensure the boundedness of estimation parameters and improve the robustness of the closed-loop system. Finally, comparative numerical simulations are performed to demonstrate that the proposed attitude control method can guarantee the boundedness of both the tracking error and estimation error.