LOW-COST, HIGH-ISP, INTEGRATED AIR-BREATHING ELECTRIC PROPULSION SYSTEM FOR HIGH ASPECT RATIO VLEO SMALL SATELLITES - EXPRO+

Objective:To develop, manufacture and test a low-cost, integrated high-Isp air-breathing electric propulsion systemsuitable for drag compensation of High-Aspect Ratio (HAR) small satellites operating in VLEO.Description:Sustainable operations in Very Low Earth Orbit (VLEO, below 250 km altitude) are currently constrained bythe propellant mass required to continuously compensate for aerodynamic drag. Air-Breathing ElectricPropulsion (ABEP) offers a potential solution by replacing conventional on-board propellant with atmosphericparticles collected through a suitably designed intake and delivered to Electric Propulsion thrusters for thrustgeneration and drag compensation.Previous ESA and non-ESA studies, supported by early-stage technology development activities, have demonstrated the feasibility of the ABEP concept and its strong potential to enable a range of applications, inparticular Telecommunications (D2D / D2H) and high-resolution Earth Observation missions. To reduce the propulsion effort required to counteract aerodynamic drag and prevent orbital decay, VLEO platforms typically adopt slender spacecraft configurations with optimised drag area, typically based on a High-Aspect Ratio (HAR) topology. This activity specifically addresses ABEP systems designed for such drag-areaoptimisedsmall satellites. The ABEP systems will be capable of operating across varying atmospheric densityand composition regimes, accounting for diurnal and seasonal variability, and across altitudes below 250km.Lifetime assessment is required, including appropriate material selection to withstand high-velocity particleimpacts and Atomic Oxygen (ATOX) exposure.The feasibility of integrated ABEP systems for this class of small satellites has already been demonstrated upto TRL 3. This activity aims to mature the technologyat system level through the design, manufacture, andtesting of a fully integrated ABEP system capable of providing continuous dragcompensation for HAR smallsatellites operating in VLEO. The expected outcome is a validated ABEP system at TRL 4, including intake,thruster, fluidics and Power Processing Unit (PPU). Successful completion of the activity will provide a compact and efficient drag-compensation solution to support sustained VLEO operations and address emerging market needs for future VLEO constellations.The activity encompasses the following tasks:- Consolidation of the ABEP system requirements for a High-Aspect Ratio small satellite.- Design, manufacturing, assembly and integration of a fully integrated ABEP system (including PPU,thruster, intake, fluidics).- Perform a functional verification test and performance mapping at system level in VLEO-representativetest conditions.- Define the thrust control laws for drag compensation based on the results achieved in the test campaign.- Perform a short endurance (250h) test that showcases performance stability and lack of early-life failuremechanisms.