Three Dimensional Guidance against Helix Maneuver with Unknown Turning Rate

Abstract

This paper deals with target interception that is performing a three dimensional helix maneuver with unknown turning rate. In practice neither the turning rate is known nor do its components thus they need estimation. The guidance law requires the turning rate vector. The simplest approach to deal with the 3D guidance and estimation is to consider three separate problems. In reality there is coupling between axes in the equations of motion in 3D. Two representations of helix trajectory that exploit this coupling are presented, the partially-coupled and the strongly-coupled representations. These representations are used to derive guidance schemes - estimator and guidance law. Simulation results compare the RMS miss distance and control effort of the different representations in the Pareto plane. It is shown that the usage of guidance laws that takes into account the coupling leads to improved performance especially when the barrel roll rate turning rate is unknown.