Obstacle Avoidance Guidance and Control Algorithm for Spacecraft Maneuvers

Abstract

This paper outlines a method that solves for optimized satellite maneuvers in the presence of obstacles. This method constitutes an optimized plan in which the dynamics are directly incorporated in a guidance and control algorithm. The method performs a 3-D static optimization over the final relative position and time-of-flight for an appropriate cost function which uses the solution to the dynamics. Specifically, it must be a function of the impulsive thrust vector Δv which is defined as a maneuver from one relative relative position to another for a given time-of-flight and final relative position. This method utilizes the ability to alter the trajectory by varying the time-of-flight and final relative position inside the Δv expression. Therefore, a search algorithm can optimize for particular forms of cost as well as avoid obstacles by including them as inequality constraints. A feedback mechanism is also incorporated by replanning in either constant or variable type intervals.