NASA 1998 SBIR Phase I


PROPOSAL NUMBER: 98-1 18.04-5565A

PROJECT TITLE: COLLOID THRUSTERS FOR MICRO AND NANOSATELLITES

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

The missions of microsatellites are constrained by lack of suitable propulsion. Examination of the propulsion options for such satellites, capable of fulfilling primary and ACS functions, leads to FEEP and colloid thrusters. The colloid thrusters are capable of efficient operation in the Isp range of most interest (1000 to 2000 seconds) while avoiding the undesirable liquid metal propellants used by the FEEPs. Glycerol fueled colloid thrusters demonstrated in the early 1970's achieved 70% efficiency at few watts of input power, 1500 sec specific impulse and lifetime exceeding 4000 hours. Busek Co. Inc, in collaboration with the MIT Space Systems Laboratory proposes to build upon this demonstrated achievement by developing a colloid thruster capable of higher performance at drastically reduced thruster weight. This will be achieved by: (1) performing fundamental investigation and modeling of colloid formation and charging to maximize its charge to mass ratio which will lead to reduced operating voltage; (2) careful design to minimize thruster dimensions while preserving safe electrical breakdown margins; and (3) use of novel miniaturization and fabrication techniques developed for MicroElectroMechanical (MEM) devices. Beam neutralizations on spacecrafts will be accomplished by use of field emission cathodes as those currently under development at Busek and elsewhere.

POTENTIAL COMMERCIAL APPLICATIONS

A low cost batch-fabricated colloid thruster capable of primary and ACS propulsion would revolutionize the use of microsatellites; colloid propulsion would enable the replacement of a large expensive satellite with multiple low cost microsatellites having extended life in orbit. Without such propulsion, microsatellites in low earth orbit would have a useful life of weeks to months, whereas with it, years will be possible. Additional benefits brought about by distributed multiple assets include lower risk, higher availability, faster replacement, etc. It is reasonable to anticipate that low cost, reliable and efficient colloid thrusters will enable rapid proliferation of micro and nanosatellites, benefiting government and commercial users.

NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR

Dr. V. Hruby
Busek Co. Inc.
11 Tech Circle
Natick , MA 01760-1023

NAME AND ADDRESS OF OFFEROR

Busek Co. Inc.
11 Tech Circle
Natick , MA 01760-1023