Operations, Orbit Determination, and Formation Control of the AeroCube-4 CubeSats

Abstract

Three satellites of the AeroCube-4 series built by The Aerospace Corporation were launched in September 2012 from Vandenberg Air Force Base. These satellites were each equipped with an on-board GPS receiver that provided position measurements with a precision of 20 meters and enabled the generation of ephemerides with meter-level accuracy. Each AeroCube was also equipped with two extendable wings that altered the satellite’s cross-sectional area by a factor of three. In conjunction with the GPS measurements, high-precision orbit determination detected deliberate changes in the AeroCube’s drag profile via wing manipulation. The AeroCube operations team succeeded in using this variable drag to re-order the satellites’ in-track configuration. A differential cross-section was created by closing the wings of one satellite while the others’ remained open, and the relative in-track motion between two AeroCubes was reversed. Over the course of several weeks, the satellites’ in-track configuration was re-ordered, demonstrating the feasibility of CubeSat formation flight via differential drag.