In this paper, an on-line suboptimal midcourse guidance law, which is a neu
ral-network approximation of the optimal feedback strategy, is proposed to
eliminate the need for solving two-point boundary-value problems in real ti
me. Moreover, for intercept point prediction, a fast converging, iterative
algorithm based on a neural network time-to-go estimator is devised. Comput
er simulations confirm that the closed-loop behavior of the proposed guidan
ce law is so close to the optimal trajectory that it outperforms nonoptimal
guidance laws such as g-biased proportional navigation. (C) 1998 Elsevier
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