Target State Estimation for Integrated Flight Control

Abstract-An extended Kalman filter for estimating the states and parameters of a target vehicle undergoing complex motions for use with an integrated guidance-control law is presented. Nonlinear point-mass model of the target including gravitational and aerodynamic forces are considered in the formulation. Target motions are modeled by a second-order oscillatory dynamic system modulating the aerodynamic normal force, together with aerodynamic drag and the acceleration due to gravity. Based on an error analysis, line-of-sight angles, line-ofsight rates, range and range rate measurements are then chosen for the implementation of the estimator. The estimator provides the target states for the integrated guidance-control of an interceptor employing an internal actuation system. Sample results are given.