Pump-fed Micropropulsion System for High Performance Nanosats

Miniaturization of propulsion systems for nanosats 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 II SBIR, Flight Work Inc. conducted the preliminary design of a pump-fed micropropulsion system and demonstrated the potential of the technology by developing and characterizing a low cost micro-pump for HAN-based propellants (TRL of 4). The system has a dry mass less than 1 kg (for 4 kg of propellant), uses less than 25 W of power, and generates more than 3.4 N of thrust at a predicted 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 for propellant storage. Under the Phase II effort, Flight Works proposes to refine the propulsion system design and develop a prototype of the system. Also included in the work plan is the development of a pump for hydrazine monopropellant, a pump which will then be integrated into a complete micropropulsion system and static fire tested in a vacuum chamber. This demonstration will pave the way towards an in-flight application of the technology onboard nanosats and microsats. BENEFIT: Whether used with hydrazine, HAN-based propellants or in bipropellant mode (MMH/NTO), the technology is particularly relevant for nanosat and microsat missions requiring high propellant mass fractions. It can also be an enabler of future missions where it might be more cost effective to send a fleet of nanosats rather than a single, larger, highly reliable –and expensive– spacecraft. In all these applications, eliminating several hard-to-miniaturize components (such as high pressure valves, tanks and regulators) reduces system cost and mass, while also allowing for more compact and lighter propellant tanks. As such, the technology is not only applicable to all DoD very small spacecraft programs with significant mission ∆V, but it also enables the more demanding ones of these missions as long as the thrust requirements can be matched with the power available on the spacecraft. In summary, applications include all small spacecraft and small landers (where the pump provides a simple throttling mechanism). The technology could also be applied to large spacecraft attitude control systems by reducing storage tank and feed-line mass.