Augmented Pursuit Guidance for Flight Trajectory Shaping

Abstract

This paper proposes a novel approach for trajectory shaping based on pursuit guidance. The relationship between the trajectory shape and the lead angle is derived for a class of trajectories expressed as polynomials of the downrange. Then pursuit guidance is augmented to control the lead angle by treating the lead-angle command as a bias signal in the lead-angle feedback loop. Approximations of the lead-angle command are also suggested for simple implementation and the lead-angle tracking error and the miss distance are analyzed for a trajectory of a quadratic curve. Numerical examples are provided to show that the proposed method is useful for finding a suboptimal trajectory for terminal speed maximization.