Variable structure guidance with auto-generated impact angle constraint based on fuzzy strategy

摘要

An appropriate impact angle constraint can not only decrease the approaching velocity but also enlarge the effective collision area of hypersonic interception, improving the interception probability. Based on the principle of quasi parallel approaching, the impact angle constraint is converted into line-of-sight angle constraint according to the initial estimation of target velocity and velocity vector. The guidance law with line-of-sight angle constraint is presented via variable structure control. On the basis of qualitative analysis on interception performances, the fuzzy strategy is proposed to generate the appropriate impact angle and weight coefficient of constraint. It is concluded that, the proposed guidance achieves to guide the line-of-sight to close to zero as well as reach the expected impact angle that automatically generated by the fuzzy controller. Moreover, the miss distance and applicability to target information estimation error are satisfied.