Collision-geometry-based optimal guidance for high-speed target

This paper proposes a new unified form of guidance law based on the collision geometry that can be applied to both head-on (HO) or head-pursuit (HP) engagements for intercepting a target faster than an interceptor. To this end, two possible collision courses for a high-speed target and corresponding nonlinear heading errors are first investigated. The proposed guidance is then determined in a way to specify the desired heading error dynamics that ensures an optimal decreasing pattern. The characteristics of the proposed method are also investigated compared to existing methods. The favorable features are that the engagement geometries between HO or HP can be flexibly selected, and the optimality of the guidance command can be addressed. Moreover, since the proposed guidance law is directly derived from nonlinear collision geometry, the working mechanism is clearly explained, and the nonlinear nature is preserved. Finally, numerical simulations are performed to support our findings.