Homing Missile Guidance and Estimation Under Agile Target Acceleration

Abstract

Two new algorithms for homing missile guidance and estimation in the two-dimensional intercept problem are proposed based on the assumption that certain targets execute evasive maneuvers orthogonal to their velocity vectors. The objectives of both algorithms are to estimate the engagement states in the presence of unknown target accelerations and guide the interceptor to hit the target based on these state estimates. Both algorithms are the integration of a fllter in cascade with a guidance law but constructed using difierent philosophies. One algorithm constructs the fllter that estimates the target acceleration and the guidance law based on a target model in which the magnitude of the target acceleration vector is assumed to be a sinusoidal function. The other algorithm constructs the fllter by blocking the dynamic efiect of the target acceleration and constructs the guidance law based on the anticipated worst possible target acceleration. These two algorithms form an interesting design trade between the inherent estimation lag and increased estimation uncertainty.