Tracking and Interception of a Spiralling Ballistic Target on Reentry

Interception of the high velocity spiralling target requires accurate estimation of their relative states. In this work, the dynamics of spiralling target is modelled by representing the target acceleration through sinusoidal function in the inertial frame. A system model which consists of nine state variables is considered here with the three relative positions, three relative velocities, inverse of ballistic coefficient, manoeuvring coefficient and spiralling frequency of target. Non-linear state estimators, namely the unscented Kalman filter (UKF), new sigma point Kalman filter (NSKF) and cubature Kalman filter (CKF), are applied to track the spiralling target using the measurements obtained from an inbuilt seeker of the interceptor missile. Further, the estimated states are provided to a guidance block for generating interceptor missile accelerations. Performance comparison of state estimators in combination with PNG law is done by calculating the root mean square error(RMSE) of relative states and average miss-distance. Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)

Automated summary

This paper investigates the interception of high velocity spiralling targets and proposes a method based on nonlinear state estimators for generating interceptor missile accelerations. The performance of different estimators in combination with the PNG law is evaluated through comparisons.