The Design, Development and Testing of a Propulsion System for the SNAP-1 Nanosatellite

Abstract

It has frequently been proposed to use very small nanosatellites for missions requiring orbital agility. Whether it be swarms of satellites for scientific or remote-sensing measurements, constellations for communications or single satellites for remote inspection, all require some way of modifying their respective orbits. Novel, high-technology solutions to this requirement have been proposed from MEMS to solar sails. Notwithstanding the eventual availability of such advanced nanosatellite propulsion technologies, the Surrey Space Centre has developed a miniature propulsion subsystem using technology readily available today. On 28th June 2000 Surrey launched SNAP-1, the first in a series of Surrey Nanosatellite Application Platform missions. Amongst other features of this new 6.5 kg nanosatellite is a butane liquefied gas propulsion subsystem to meet the spacecraft's mission requirement of 1 m/s delta V. With a total mass budget of 450 grams, including propellant, dry mass, structural support and drive electronics, this propulsion system will be one of the smallest ever to have flown on a spacecraft. This paper describes some of the interesting challenges in producing such a small system, especially in a seven month "concept to launch site" program. The flight propulsion system will be described, including novel techniques such as using a coiled tube in the place of a conventional propellant tank. The choice of butane as a propellant will be discussed.