Optimal strategies found using genetic algorithms for deflecting hazardous near-earth objects

Abstract

Potentially hazardous asteroids can be deflected away from the Earth using a kinetic impactor spacecraft. An optimal control problem is solved to find the time history of thrust magnitude and direction to steer the low-thrust spacecraft from the Earth to the asteroid so that the impact maximizes the resulting miss distance. Because the solution space considered by the optimizer is large and the objective function is complicated, intuition is not sufficient to provide an adequate initial guess for the nonlinear programming problem solver used to optimize all aspects of the trajectory. A recently developed shape-based trajectory approximation method coupled with a genetic algorithm is used to provide this initial guess to the optimizer and make the problem tractable.