An Algorithm for Determination of Projectile Attitude Angles in Projectile Trajectory Prediction

A fast and accurate algorithm is established in this paper to increase the precision of ballistic trajectory prediction. The algorithm is based on the six-degree-of-freedom (6DOF) trajectory equations, to estimate the projectile attitude angles in every measuring time. Hereby, the algorithm utilizes the Davidon-Fletcher-Powell (DFP) method to solve nonlinear equations and Doppler radar trajectory test information containing only position coordinates of the projectile to reconstruct the angular information. The "position coordinates by the test" and "angular displacements by reconstruction" at the end phase of the radar measurement are used as an initial value for the trajectory computation to extrapolate the trajectory impact point. The numerical simulations validate the proposed method and demonstrate that the estimated impact point agrees very well with the real one. Morover, other artillery trajectory can be predicted by the algorithm, and other trajectory models, such as 4DOF and 5DOF models, can also be incorporated into the proposed algorithm. © 2018, Editorial Department of Transactions of NUAA. All right reserved.