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Green Propellant Rapid Orbital Mobility Bus

Completed

Description

Parabilis Space Technologies is pleased to propose the development of a low cost, high thrust, hybrid propulsion module using indefinitely storable, non-toxic, green technology propellants to provide rapid mobility for collision and threat avoidance as well as enhanced orbit insertion, deorbit, and disposal. The solution is designed to operate in LEO to Cislunar orbit regimes and scalable to support payloads or spacecraft ranging from Cubesats to ESPA Grande class smallsats. ROMBUS-Evolved (ROMBUS-E) is steered via gimbaling the entire hybrid motor, which is enabled by a novel case design and the short form factor of the motor. Nitrous oxide is stored in four tanks in the corners of the vehicle, which also provide the primary load path between the launch vehicle MLB and the payload. The entire stage fits within a 24-inch by 28-inch by 22-inch height volume. Benefits include significantly lower cost than traditional mono-prop or bi-prop chemical systems, indefinitely storable on-orbit or on the ground, high thrust for rapid mobility, throttleable and restartable, and low freezing non-toxic propellants. The baseline concept will provide over 1000 m/s delta-v to small payloads and 635 m/s to a 105kg payload. The design is scalable to larger payloads. During Phase I, Parabilis will manufacture, and test a nitrous-oxide reaction control system, burning down both technical risk and the effort required for a successful hot fire test in a subsequent Phase II effort. This effort leverages previous successful NASA-funded R&D at Parabilis for a “NanoLaunch” hybrid upper stage in addition to over 3 years of Smallsat hybrid propulsion R&D efforts for a Proprietary major aerospace company. This approach will rapidly and substantively reduce risk for further Phase II development.

Benefits

The proposed solution is applicable to a wide range of NASA small satellites (e.g. SMEX) and missions that currently do not have affordable, responsive propulsion systems or need an additional stage to reach operational orbit and/or perform end of life disposal. Additionally, ROMBUS-E can provide responsive “cold start” impulsive maneuvers to avoid collision with debris or potential adversary threats. Similar to NASA applicability, ROMBUS-E is applicable to commercial and DoD small satellites that currently do not have affordable, responsive propulsion. DoD satellites that may be targets during times of conflict can benefit from low cost, rapid maneuvers to avoid potential adversary threats. Large constellations that are not at LEO altitudes can affordably de-orbit using this solution.

Details

Technology areaEntry, Descent, and Landing
ProgramSmall Business Innovation Research/Small Business Tech Transfer (SBIR/STTR)
Lead organizationAmes Research Center, Moffett Field, CA
Start date2025-09-29
End date2026-03-27

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How to get involved

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

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