Target Maneuver Adaptive Guidance Law for a Bounded Acceleration Missile

摘要

A new multiple-model adaptive estimator-guidance law is presented for a bounded acceleration interceptorrnpursuing a target performing a sudden step maneuver. The estimators proposed for each model in the filter bankrndiffer in the expected timing of the targetmaneuver jump and feature amechanismconstructed to efficiently identifyrnsuch a jump. The certainty equivalence principle seems to be invalid in the case of bounded missile acceleration.rnHence, the resulting guidance gain for each target model, calculated using an equivalent random input describingrnfunction, depends on themeasurement noise level, targetmaneuver statistics, and saturation limit.These gains can berncomputed a priori and stored in a lookup table to be used online, and are different for each targetmodel in the bank.rnIn contrast, the expressions for the zero-effortmiss for allmodels are identical; however, their value is independentlyrnevaluated by each estimator in the bank and, hence, are in general different. Simulation results show significantrnimprovement over the deterministic optimal guidance law when jump times vary from10 to 3missile time constantsrnbefore intercept. A sensitivity analysis to various noise levels and expected target maneuvers was carried out,rnemphasizing the robustness and advantages of this scheme.