ENPULSION NANO and MICRO propulsion systems: from flight heritage to design updates

Over 300 NANO and MICRO propulsion systems have been deployed in space, servicing a variety of customers, missions and applications in large number of different orbits and platform sizes. The significant flight heritage gained from these units has been continuously used to improved design and operations of the systems. While the NANO propulsion system is operated at total system input power levels of up to 40W and is often utilized in multi-thruster configurations on platforms between 40 and 100 kg, the MICRO is a propulsion system of up to 120W nominal total system input power oriented towards larger platforms. Both propulsion systems are based on liquid metal Field Emission Electric Propulsion (FEEP) technology, with a solid propellant during storage, integration and launch, that is later liquified on orbit. We present significant design updates to both propulsion systems, including the novel extractor geometries employed. We present the development process and ground testing of these new systems addressing the known extractor clogging phenomenon observed in FEEP propulsion systems, including exhaustive simulation efforts to optimize extractor geometries.