Optimal sliding mode guidance law against maneuvering target with impact angle constraint

In this paper, an optimal sliding mode guidance law with impact angle constraint is proposed against maneuvering targets. Firstly, the impact angle frame for a static target is extended to a maneuvering target. Then, in this impact angle frame, the optimal reaching law of sliding mode is proposed to design an optimal sliding mode guidance law which is robust to target maneuvers and satisfies an impact angle constraint. The optimal sliding mode guidance law with impact angle constraint is also extended to the three-dimensional case. Numerical simulations in different scenarios with a realistic missile model show that the guidance law can intercept a maneuvering target with a desired impact angle, and the control effort is close to the optimal value, which verifies that the proposed optimal sliding mode guidance law has both robustness and optimality.