Minimum effort intercept and evasion guidance algorithms for active aircraft defense

The paper proposes a new approach to guidance algorithm design for the target-attacker-defender problem based on the idea of specifying the desired performance in terms of miss distance and of optimizing the effort required to achieve it. Using this approach, guidance algorithms are designed separately for the defender and the target. The pursuit guidance algorithm for the defender uses the fact that the attacker is pursuing the target in order to improve the prediction of the attacker motion and thus its guidance performance. The evasion guidance algorithm for the target weighs in the fact that aggressive evasion maneuver will determine aggressive interception maneuvering from the part of the attacker, making the task of the defender more difficult. The guidance design problems are formulated as optimal control problems, and the solutions of these optimal control problems are used as guidance laws that use variables that are either directly obtainable from sensor measurements or estimates obtained from filtering these measurements. Using simulation results, the performance of the proposed guidance laws is demonstrated under perfect information assumption as well as in the presence of estimation errors.