Two-stage cooperative guidance strategy using a prescribed-time optimal consensus method

This paper addresses the optimal decentralized three-dimensional cooperative guidance problem for multiple interceptors against a stationary target considering dynamically changing and directed communication topologies. A two-stage cooperative strategy is proposed to achieve simultaneous attack regardless of the information on time-to-go. More specifically, a prescribed-time optimal consensus method is applied in the process of the first-stage distributed cooperative guidance law design to generate desired initial conditions for the latter guidance phase, where the consensus arriving time can be off-line pre-appointed according to interception mission requirements without conservative estimation and is independent of the initial conditions of interceptor's states. Furthermore, the optimal consensus control under directed and periodical switching topologies is also considered in the first guidance phase, and the analytically optimal cooperative guidance law is formulated based on Pontryagin's principle. As for the second guidance phase, all interceptors are switched to typical pure proportional navigation guidance law, and the salvo attack can be achieved eventually. Extensive numerical simulations are performed to validate the effectiveness and superiority of the proposed cooperative guidance scheme.