Abstract:

Aiming at the situation that the extra-atmospheric interceptor still needs to fly without control for a long time after the midcourse guidance, the relative motion relationship between interceptor and target is theoretically deduced by using the optimal control theory based on the zero effort miss. Then a midcourse guidance strategy with a fixed propulsion time of the interceptor engine is proposed, which is taking miss distance and midcourse guidance acceleration as performance indexes. Finally, the relationship between the guidance accuracy of the interceptor and the prediction accuracy of zero effort miss is studied, and the way to adjust the maneuver overload of interceptor is proposed. The simulation results show that the designed midcourse guidance law has high precision, good reliability and simple form. When the miss distance calculation is accurate enough, the zero effort miss after midcourse guidance can be controlled within 100 meters, which creates excellent terminal guidance conditions for the interceptor to intercept the target by kinetic energy collision.

Key words: guidance law, midcourse guidance, interceptor, zero effort miss