Composite Guidance Law Against Maneuvering Target Considering Impact Angle Constraints

To intercept maneuvering targets with minimum miss distance and desired impact angles in finite time, this paper proposes a composite guidance law that contains adaptive sliding mode disturbance observer (ASMDO), nonsingular terminal sliding mode (NTSM) technique, and adaptive supertwisting (ASTW) technique. The ASMDO is implemented to estimate the target maneuver and its output is utilized as a feedforward control component. It is worth noting that the proposed observer does not require prior information about target acceleration. Considering the superiority of the NTSM technique, a guidance law based on NTSM is designed to drive angle and angular error converged in finite time. Moreover, to avoid the inherent chattering problem of sliding mode control, the adaptive sliding mode control technique is also employed. In addition, the finite time stability of the closed-loop system is demonstrated via the Lyapunov method. Finlay, the numerical simulations are established to verify the effectiveness of the proposed composite guidance law.