Pump-fed Micropropulsion System for High Performance Nanosats

Miniaturization of propulsion systems for small spacecraft presents unique challenges which, to date, have rendered such small spacecraft unable to have significant orbit change/control and attitude control capabilities. Under a Phase I SBIR, Flight Work Inc. will design a HAN-based pump-fed micropropulsion system and demonstrate the potential of the technology by developing and characterizing a low cost micro-pump for HAN-based propellants. The goal is to develop a system with dry mass less than 1 kg (for 4 kg of propellant), less than 25 W of power, more than 0.1 N thrust, and ISP greater than 240 s. The introduction of the pump in the system allows eliminating relatively heavy valves, regulators and lines while using plastic tanks/bags for propellant storage. This reduction in system complexity and mass will allow nanosats to conduct missions with ∆V’s similar to those of today’s larger spacecraft. The pumps are based on proven recently-developed high performance gear pumps driven by DC motors and developed for small turbojets, UAV’s gasoline engines, methanol fuel cells and other applications. Also, because the power to the pump can be modulated, thrust is easily controlled and adjusted to best match mission needs.