Patent Number: 6,253,124

Title: Low energy method for changing the inclinations of orbiting satellites using weak stability boundaries and a computer process for implementing same

Abstract: When a satellite is orbiting the earth in an elliptic orbit, it has a certain inclination with respect to the earth's equator. The usual way to change the inclination is perform a maneuver by firing the rocket engines at the periapsis of the ellipse. This then forces the satellite into the desired inclination. There is a substantially more fuel efficient way to change the inclination. This is done by an indirect route by first doing a maneuver to bring the satellite to the moon on a BCT (Ballistic Capture Transfer). At the moon, the satellite is in the so called fuzzy boundary or weak stability boundary. A negligibly small maneuver can then bring it back to the earth on a reverse BCT to the desired earth inclination. Another maneuver puts it into the new ellipse at the earth. In the case of satellites launched from Vandenberg AFB into LEO in a circular orbit of an altitude of 700 km with an inclination of 34.degree., approximately 6 km/s is required to change the inclination to 90.degree.. The previous flight time associated with this method was approximately 170 days. A modification of this method also achieves a significant savings and unexpected benefits in energy as measured by Delta-V, where the flight time is also substantially reduced to 88 or even 6 days.

Inventors: Belbruno; Edward A. (Princeton, NJ)

Assignee: Galaxy Development

International Classification: B64G 1/00 (20060101); B64G 1/24 (20060101); B64G 001/24 (); B64G 001/10 ()

Expiration Date: 06/26/2018