Orbital Express spacecraft to test ability to rendezvous without human help

William Atkins
Tuesday, 06 March 2007 07:36

Science - Space

Orbital Express is scheduled to be launched aboard a Lockheed Martin Atlas 5 rocket from NASA's Cape Canaveral in Florida on March 9, 2007, as part of the U.S. Air Force’s Space Test Program-1 (STP-1). (The Atlas 5 rocket was manufactured by Lockheed Martin. The Orbital Express mission will be its first flight.)

When it reaches its orbit, Orbital Express will deploy two satellites: ASTRO (Autonomous Space Transport Robotic Operations) and NextSat (Next-generation serviceable Satellite).

A team of engineers from DARPA and NASA’s Marshall Space Flight Center are managing the mission. DARPA (Defense Advanced Research Projects Agency), an agency of the Department of Defense, is responsible for the development of new technologies for use with the U.S. military. It was first established by the United States in response to the Soviet Union’s launching of the first artificial satellite, Sputnik 1 in 1957—what is generally considered the beginning of the Space Race that eventually placed two astronauts on the Moon in 1969.

The servicing craft ASTRO was built by Boeing Integrated Defense Systems and the serviceable craft NextSat was built by Ball Aerospace and Technologies Corporation.

During the mission, ASTRO will dock with NextSat and service it with the use of its mounted AVGS (Advanced Video Guidance Sensor) system. AVGS will send a coded pattern of retro-reflectors onto the surface of NextSat. In response, ASTRO will automatically modify its speed and approach angle in order to safely make contact with its target.

In all, eight tests will be conducted over a three-month timeframe, both in sunshine and in darkness. Some of the tests include approach and docking maneuvers; exchange and installation of batteries; and exchange of propellant.

If the tests are successful, the new robotic spacecraft could lead to automated servicing operations and technologies that include rendezvous, proximity operations, station-keeping, docking capture, repair, fluid and fuel transfer, and component replacement.

Space engineers predict the use of autonomous rendezvous and docking systems sometime in the next decade if such prototype spacecraft as Orbital Express become seen as a viable alternative to human operated craft for space-related repair and recovery activities.

Additional information about Orbital Express is found at: http://www.darpa.mil/tto/programs/oe.htm (DARPA), http://www.ballaerospace.com/oexpress.html (Ball Aerospace), and http://www.boeing.com/ids/advanced_systems/orbital.html (Boeing).