What is the Naval Research Laboratory's Future in Space?By John Ohab | September 27, 2011
Wilhelm began his NRL career in 1959, not long after Sputnik, Explorer, and Vanguard hit the skies, and he has played a leading role in many of NRL's pioneering space achievements, from electronic intelligence gathering to GPS to tactical microsatellites. Wilhelm singles out two technologies he thinks could be game-changing and that he would like to see NRL take into the future: electrodynamic propulsion systems and low-cost launch vehicles.
Electrodynamic propulsion technology exploits the Earth's magnetic field to allow a spacecraft to maneuver without expending precious fuel.
This is a revolutionary technology, explains Wilhelm, that will enable satellites to conduct missions that cannot be done right now, including moving between significantly different orbital inclinations.
NRL has already built and tested a proof-of-concept spacecraft, TEPCE (Tether Electrodynamic Propulsion Cubesat Experiment), to be launched next year. TEPCE consists of two microsatellites at the ends of a 1-kmlong, conducting tether; electrons are collected at one end of the tether and emitted at the other, producing a force which changes the satellite's orbit. The force is determined by the length of the tether, the amount of current, and the strength of the Earth's magnetic field.
NRL proposes to take this technology to the next step by developing a 3-km-long tether divided into three sections, each with separate control of the magnitude and direction of the current.
This allows for refined maneuvering so the spacecraft can rendezvous with other spacecraft and space objects, and then use cameras and robotic arms to 'see' and grasp them, says Wilhelm. We envision this kind of spacecraft delivering payloads to orbiting satellites through the use of plug-in interfaces; and also servicing ailing spacecraft, and capturing and de-orbiting space debris.
Wilhelm also wants to develop small, low-cost launch vehicles: Launch has been unpredictable and expensive since day 1 in space exploration, and there are still delays and failures. NRL and other satellite developers can now rapidly design and build small, highly capable satellites, but the holdup is still in getting the satellite into orbit.
The Department of Defense is the most likely developer of a better launch vehicle, benefiting most from the rapid deployment it will enable. Standardized spacecraft, already being built in the Operationally Responsive Space (ORS) initiative, will be assembled and launched within days to meet immediate mission needs. I want to see NRL work with the ORS Office and the Army to make this happen.
What keeps NRL at the forefront of space research and technology for the future? Wilhelm's answer comes easily:
NRL invests in talented researchers and top-notch facilities. We have a solid and reliable base of expertise, so when we're presented with a new problem, we have the knowhow and imagination and facilities and flexibility to tackle it. This has always been our strength.
The story was originally published in the September 2011 Limited Edition issue of SPECTRA, the magazine of the Navy's Corporate Laboratory.