Grant: Research Tools and Instruments - Category 1 (<$150,000)

The objective of this experimental program is to design an air table experiment system able to test the tether deployment mechanism of a nano-satellite end-of-mission deorbiting device in a simulated space environment of zero gravity.     Nano-satellite end-of-mission deorbitors are small devices that use electrodynamic tether (EDT) drag to deorbit a nano-satellite. Because it uses passive electromagnetic interactions with the Earth's magnetic field to lower the orbit of the spacecraft, it requires neither propellant nor power. Thus, it can achieve autonomous deorbit of a nano-satellite with very low mass requirements. As more and more universities around the world are able to launch nano-satellites for their educational programs, it is important for future launchers to remove the end-of-mission nano-satellites from space in order to safeguard spacecrafts from space debris. Several EDT demonstration missions have flown since 1992. However, many failed prematurely due to ENGINEERING problems including the most recent MAST mission in April 2007, where the tether failed to deploy. The critical engineering problems encountered by the EDT system include: (1) tether deployment, and (2) stability of the tether system. The tether will be deployed by the end mass expelled from the host satellite using either spring force or other mechanical means. Insufficient spring force will fail the deployment due to the system damping, while large spring force without proper control may slack or snag the tether, resulting in the tether recoil or the rebound of end mass to endanger the host. The proposed research program will address the engineering problems by developing and testing a highly reliable EDT system using an air table to simulate space environment of zero gravity. It will help in providing insights into the design of the nano-satellite end-of-mission deorbiting device to discover some fundamental issues which may be overlooked by existing theories. The proposed equipment will train HQPs in the design of experiments, advanced measurements and instruments. The outcome of the proposal will enhance the space engineering program at York University.