SBIR-STTR Award

The Air Force needs an autonomous service vehicle to inspect, repair, upgrade, or refuel future satellites configured for on-orbit servicing. Such a vehicle must be very low mass, with a high power output for electric propulsion. Conventional ion rockets or arcjets may not have the delta-V/mass ratio required for the mission. Star Technology and Research, Inc. proposes a concept of a maneuvering satellite that requires no expenditure of fuel for fulfilling Air Force orbital service missions. The mechanism to accomplish this is an advanced electrodynamic tether powered by lightweight solar panels to allow repeated orbital maneuvers without using propellant. Controlling the current flow in the tether allows complete control of the orbit. The vehicle could transport satellites from one orbit to another, and could service vehicles beyond low Earth orbit. In this Phase I investigation, the satellite concept is developed, its operational envelope is examined, and potential Air Force applications are evaluated. A proof-of-concept experiment is proposed for a low-cost space demonstration.

The Air Force needs an autonomous service vehicle to inspect, repair, upgrade, or refuel future satellites configured for on-orbit servicing. Star Technology and Research, Inc. examined the feasibility of such a vehicle powered by electrodynamic tether in Phase I of this effort, and found that the tether-powered service vehicle would be 2-4 times as efficient as ion rockets for high-inclination orbit changes. The vehicle, using a meteor-safe electrodynamic tether powered by lightweight solar panels, could service constellations of satellites in widely separated orbital planes over a period of months without fuel. In this Phase II effort, prototype flight hardware will be developed and delivered that will be suitable for a proof-of-concept space experiment. A control system to modulate the electrical current in the tether to control tether librations will be developed. These deliverables form the core requirements for a commercial product.

Keywords:
ELECTRODYNAMIC TETHERSPACE MANEUVERING VEHICLE ORBIT TRANSFER ON-ORBIT SERVICING TETHER LIBRATION