A Modified Proportional Navigation Guidance Law for Impact Time Control

In this paper, a modified proportional navigational guidance (MPNG) law is proposed for the impact time control. When the leading angle is large, the precision of the traditional time-to-go estimation method is poor. To solve this problem, a more accurate expression of the time-to-go estimation of proportional navigation guidance (PNG) law is first proposed. Second, in order to meet the impact time control requirement, a term of impact time error feedback is added on the PNG law. When the leading angle is zero, some existing impact time control laws cannot satisfy the impact time constraint. To solve this problem, an addition command is designed. Finally, the MPNG law constructed in this paper can not only satisfy the requirement of the impact time control and different initial leading angles, but also can be applied to the cooperative attack scenario. Numerical simulations are performed to demonstrate that the proposed method is effective and applicable.