Satellite formation flight and realignment maneuver demonstration aboard the International Space Station
Mandy, Christophe P., et al. (2007). "Satellite formation flight and realignment maneuver demonstration aboard the International Space Station." 6687: 66871F-66871F-9
The Synchronized Position Hold Engage and Reorient Experimental Satellites (SPHERES), developed by the MIT Space Systems Laboratory, enable the maturation of control, estimation, and autonomy algorithms for distributed satellite systems, including the relative control of spacecraft required for satellite formation flight. Three free-flyer microsatellites are currently on board the International Space Station (ISS). By operating under crew supervision and by using replenishable consumables, SPHERES creates a risk-tolerant environment where new high-risk yet high-payoff algorithms can be demonstrated in a microgravity environment. Through multiple test sessions aboard the ISS, the SPHERES team has incrementally demonstrated the ability to perform formation flight maneuvers with two and three satellite formations. The test sessions aboard the Space Station include evaluation of coordinated maneuvers which will be applicable to interferometric spacecraft formation missions. The satellites are deployed as a formation and required to rotate around a common center about a given axis, mimicking an interferometer. Various trajectories are then implemented to point the synthetic aperture in a different orientation by changing the common axis of revolution. Observation-time optimizing synchronization strategies and fuel balancing/fuel optimizing trajectories are discussed, compared and evaluated according to resulting mission duration and potential scientific output.