The SPHERES Guest Scientist Program (GSP) supports the efforts of geographically distributed researchers at MIT, the U.S. Department of Defense, NASA, and elsewhere, in the development of algorithms for the SPHERES formation-flying and docking testbed. The GSP consists of a test development framework, a robust and flexible interface to the SPHERES flight software, a portable high-fidelity simulation, two laboratory testbeds, and data analysis utilities. The SPHERES testbed will be operated in bi-weekly test sessions on-board the International Space Station. Updates to the flight software can be uploaded immediately prior to each test session, allowing guest scientists the opportunity to revise and improve their algorithms from one session to the next. The SPHERES flight software architecture and the GSP interface design contribute to the flexibility of the testbed, and minimize nonproductive labor by simplifying algorithm implementation.

The MIT Space Systems Laboratory (SSL) is developing the SPHERES (Synchronized Position Hold Engage Reorient Experimental Satellites) 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 technologies are critical to the operation of distributed satellite and docking missions such as TechSat21, Starlight, Terrestrial Planet Finder, and Orbital Express. The development of SPHERES follows the guidelines set in a laboratory design philosophy created from lessons learned through the development and operation of prior microgravity testbeds by the MIT SSL. The philosophy ensures that the resulting laboratory provides a risk-tolerant and cost-effective environment that facilitates the design process and reduces the development costs of unproven technologies. The testbed consists of three free flyer units which can control their relative positions and orientations in six degrees of freedom. The testbed can operate in 2D on a laboratory platform and in 3D on NASA's KC-135 and inside the International Space Station. Flight tests aboard NASA's KC-135 and studies in the ground laboratory confirm the functionality of SPHERES.

The MIT Space Systems Laboratory is developing the SPHERES formation flight testbed to provide the Air Force and NASA with a long term, replenishable, and upgradable testbed for the validation of high risk metrology, control, and autonomy technologies. These technologies are critical to the operation of distributed satellite and docking missions such as TechSat21, Starlight, Terrestrial Planet Finder, and Orbital Express. To approximate the dynamics encountered by these missions, the testbed consists of three microsatellites, or "spheres," which can control their relative positions and orientations in six degrees of freedom. The testbed can operate in 2-D on a laboratory platform and in 3-D on NASA's KC-135 and inside the International Space Station. SPHERES follows the lead of the Laboratory's MODE (Middeck 0-gravity Dynamics Experiments) and MACE (Middeck Active Control Experiment) family of dynamics and control laboratories (STS-40, 42, 48, 62, 67, MIR, ISS) by providing a cost-effective laboratory with direct astronaut interaction that exploits the micro-gravity conditions of space. Flight tests aboard NASA's KC-135 have confirmed the functionality of SPHERES as a formation flight test platform with dynamics representative of true spacecraft. Studies in the 2-D laboratory environment include master/slave algorithms and docking control.

The MIT Space Systems Laboratory is developing the SPHERES formation flight testbed to provide the Air Force and NASA with a long term, replenishable, and upgradable testbed for the validation of high risk metrology, control, and autonomy technologies. These technologies are critical to the operation of distributed satellite and docking missions such as TechSat21, Starlight, Terrestrial Planet Finder, and Orbital Express. To approximate the dynamics encountered by these missions, the testbed consists of three microsatellites, or “spheres,” which can control their relative positions and orientations in six degrees of freedom. The testbed can operate in 2-D on a laboratory platform and in 3-D on NASA’s KC-135 and inside the International Space Station. SPHERES follows the lead of the Laboratory’s MODE (Middeck 0-gravity Dynamics Experiments) and MACE (Middeck Active Control Experiment) family of dynamics and control laboratories (STS-40, 42, 48, 62, 67, MIR, ISS) by providing a cost-effective laboratory with direct astronaut interaction that exploits the micro-gravity conditions of space. Flight tests aboard NASA’s KC-135 have confirmed the functionality of SPHERES as a formation flight test platform with dynamics representative of true spacecraft. Studies in the 2-D laboratory environment include master/slave algorithms and docking control.