Radiation Hardness Assurance


IFM Nano Thruster Development: From LEO to Deepspace

Bernhard Seifert1, Thomas Hörbe2, Emre Ceribas3, Jakob Kirschner4

FOTEC Forschungs- und Technologietransfer GmbH
1 Head of Aerospace Engineering Department, seifert@fotec.at
2 Scientist, hoerbe@fotec.at
3 Scientist, ceribas@fotec.at
4 Scientist, kirschner@fotec.at



Building on the long-term experience of ion emitters and ion thrusters based on FEEP (Field Emission Electric Propulsion) technology, FOTEC started the development of the integrated propulsion system IFM Nano Thruster for CubeSats and Nanosatellites in 2015. In parallel to the miniaturization of the thruster and periphery, also the PPU (Power Processing Unit) was developed to operate the thruster. It controls the heater to liquefy the solid propellant indium, generates negative and positive high voltage to ionize and accelerate the propellant and operates the thermionic neutralizers to compensate the positive expelled ions by emitting electrons. In 2018, the first IOD (in-orbit demonstration) of the IFM Nano Thruster showed the functionality of the micro-propulsion system integrated into a 3U CubeSat.

While the TID (Total Ionizing Dose) rate in lower LEO (Low Earth Orbit) is comparatively low, it strongly increases to significant levels at altitudes of 800 km and higher. Here, the proper selection of EEE (Electrical, Electronic and Electromechanical) components is crucial to guarantee proper functionality of the PPU after a certain accumulated dose. FOTEC has performed various TID test campaigns at Seibersdorf Laboratories to verify the functionality and stability of the components resulting in a PPU that can be exposed to 30 krad TID without loss of performance.

In 2021, FOTEC started to test the PPU sensitivity to SEE (Single Event Effects) with high-energy protons (up to 250 MeV) at MedAustron, a synchrotron based medical facility. The first tests were done at system level and rasterizing the PCB allows detailed conclusions to be drawn about the individual components and their performance by correlating the spatial information of the beam with the timely logged telemetry. A full qualification campaign of the next generation FEEP propulsion systems consisting of TID and SEE tests is planned for 2022.