Numerical optimization of synergetic maneuvers

Abstract

The use of atmospheric forces to produce an orbital plane change requires less energy than a pure exoatmospheric propulsion maneuver. The combination of aerodynamic and propulsive forces to cause a change in orbital inclination is termed a synergetic maneuver. Several methods have been proposed to control the critical heating rate while performing the procedure. This thesis examines these control methods by numerically optimizing the trajectory for several fuel weights and heat rate constraints. The Program to Optimize Simulated Trajectories (POST) is used to simulate the maneuvers and control schemes and to perform the optimization. For no active heat constraints, it is shown that a gliding atmospheric entry followed by a maximum throttle bang produces significantly more inclination change than other proposed maneuvers. If the heat constraints are active, the recently proposed aerobang maneuvers produces a substantial inclination change while providing significant heating rate control and shows definite advantages over the long-studied aerocruise maneuver