Precision Munition Guidance and Moving-Target Estimation

The efficacy of a munition depends on target detection, estimation of its motion, guidance, tracking and control; in fact even more so if the target is moving. This paper is concerned with flight dynamics of a munition in atmosphere under four different guidance schemes to intercept an evasive ground target. The miss distances and commanded acceleration required by these guidance laws are compared. Two-dimensional planar flight of the munition and its pitch motion model is developed and simulated. The forward and/or backward motion of a target tank on the ground is modeled as a second-order Gauss-Markov process. To estimate the target location on the ground and the line-of-sight rate to intercept it, an Extended Kalman filter is composed whose state vector consists of cascaded state vectors of missile dynamics and target dynamics. The line-of-sight angle measurement from the infrared seeker and range measurement from the millimeter wave radar are used in the Kalman Filter for relative navigation of the munition. With navigation errors amidst sensor measurement noise, the miss distance of the munition is 1.03m. It is capable of hitting the target with high accuracy as well as minimizing the lateral acceleration demand.