Minimization of propellant requirements for low thrust transfer including coast phases in each revolution

An interesting potential application for low thrust propulsion is the raising or lowering of an orbit under the earth gravitation. With the advent of space shuttle, transfer of a payload from an initially eccentric orbit to a circular orbit has been of current interest. This paper studies minimum fuel transfers using low thrust that permit coasting phases in a single revolution, whereby we can get off with less fuel consumption than the transfers without coasting periods. The entrance or exit true anomaly of an optimal coasting arc is expressed by a cubic equation with respect to the cosine of that anomaly. Computational results are shown for the selected cases and are compared with those for the transfers without coasting arcs to result in much savings of fuel consumption.