The Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) program, developed by the MIT Space Systems Laboratory, began operations aboard the International Space Station (ISS) in May 2006. SPHERES was designed as a research facility to demonstrate metrology, control, and autonomy algorithms for distributed satellite systems. By operating in the risktolerant environment of...

The MIT Space Systems Laboratory is developing the SPHERES formation flight testbed to provide multiple investigators with a long term, replenishable, and upgradable testbed for the validation of high risk metrology, control, and autonomy technologies. These core technologies enable distributed satellite and docking missions such as TechSat21, Starlight, Terrestrial Planet Finder, and Orbital E...

The dynamics of reconfiguring a formation of spacecraft is studied. We pose the problem as a two-point boundary value problem where the initial and final positions and times are known and the necessary velocities for the reconfiguration transfers must be found. We present an algorithm that solves this problem for reconfiguration about a nominal trajectory in arbitrary gravity fields, providing ...

This thesis primarily describes performance and decision heuristics of human operators intervention with an autonomous formation flight (AFF) system during monitoring of a station-keeping display. Due to mental and physical workloads, automation technologies have been applied to formation flight for precise station-keeping and resultant fuel reduction, shifting control authority from humans to ...

Fifty-four skeins of pink-footed geese (Anser brachyrhynchus) were photographed from directly underneath to eliminate the effects of perspective distortion, and the wing-tip spacings (the distance between adjacent birds' wing tips perpendicular to the flight path at maximum wingspan) and depths (the distance between adjacent birds' body centres parallel to the flight path) were measured at the ...

Ionic Ca2+ functions as a second messenger to control several intracellular processes. It also influences intercellular communication. The release of Ca2+ from intracellular stores through the inositol 1,4,5-trisphosphate receptor (InsP3R) occurs in both excitable and nonexcitable cells. In Drosophila, InsP3R activity is required in aminergic interneurons during pupal development for normal fli...

This paper elaborates on theory and experiment of the formation flight control for the future space-borne tethered interferometers. The nonlinear equations of multi-vehicle tethered spacecraft system are derived by Lagrange equations and decoupling method. The preliminary analysis predicts unstable dynamics depending on the direction of the tether motor. The controllability analysis indicates t...

Electromagnetic Formation Flight (EMFF) is a novel propellantless propulsion technology for formation flying satellites. Actuation in relative degrees of freedom for formation flight satellites is provided using electromagnetic forces and reaction wheels. One application for EMFF is stationkeeping for fractionated spacecraft architectures. The benefit of EMFF is that by replacing thrusters for ...

The International Space Station (ISS) provides the ability for the creation of true laboratories in a microgravity environment. The availability of humans in the ISS presents a further advantage: the ability to put humans in the design loop. The MIT Space Systems Laboratory developed a new laboratory design philosophy to take advantage of these new resources. The new philosophy is implemented i...

This work considers the task of accurate in-air localization for multiple unmanned or autonomous aerial vehicles flying in close formation. The paper describes our experimental setup using two small UAVs and the details of the localization algorithm. The algorithm was implemented on two low-cost, electric powered, remote control aircraft with wing spans of approximately 2 meters. Our control so...