Optimal guidance-to-collision law for an accelerating exoatmospheric interceptor missile

Aguidance-to-collision law is presented. The guidance law is derived, using the optimal control methodology, for an accelerating exoatmospheric interceptor. It is dependent on a unique zero-effort heading angle error and on a variable denoted as the zero-effort angle of attack. The guidance law enables an accelerating interceptor to fly toward the interception point along a straight line, after the initial heading error is nulled. In addition, the guidance-to-collision law enables interception of the target with a terminal body angle. Moreover, the trajectory imposed by this guidance law enables an accelerating interceptor to estimate the target's acceleration by using bearings-only measurements. This is possible due to the imposed line-of-sight rotation, making the range between the two vehicles observable. Using a nonlinear two-dimensional simulation, the performance of the guidance law is analyzed, showing superior performance compared to that of classical proportional navigation.