NASA Selects Small Spacecraft Technologies for Funding

New high-impulse thrusters and communications technologies that will facilitate missions by groups of spacecraft beyond Earth orbit are among the small satellite technologies that NASA is funding under its Small Business Innovation Research (SBIR) program.

The space agency selected six research and development projects for SBIR Phase II funding. The awards are for up to $750,000 over two years.

Three of the proposals focus on small satellite thrusters. Alameda Applied Sciences Corporation (AASC) of Oakland, California will continue to develop its high-impulse metal plasma thrusters for use on CubeSat missions.

“AASC has met these goals with its innovative, electric propulsion thruster (MPT) that has no moving parts, uses solid propellant (non-toxic stable metals such as Mo, Nb, Pd and many others), is compact (fits into 3U CubeSats, and is modular, so scalable to 12U, 27U and even larger platforms,” the company said in its proposal summary. “The simplicity of the system and relatively low manufacturing cost make the MPT highly attractive to the CubeSat market.”

AASC said the scalable thrusters will be “fully flight qualified by a launch into space (June 2020), followed by commercial sales of multiple thruster systems to NASA and other satellite makers.”

NASA also selected ExoTerra Resource of Littleton, Colorado, to develop its modular xenon micro electric propulsion system for use on small satellites.

“ExoTerra’s Modular Xenon Micro Electric Propulsion System is a high-impulse propulsion system that enables CubeSats to alter or maintain their orbits and to perform affordable, targeted science missions throughout the inner solar system,” the company said in its summary.

“The proposed integrated system provides 4-33 mN of thrust and 36-53 kNs of impulse at an Isp from 700-1500 s using a micro-Hall Effect Thruster, and can package in 9U of volume to meet the tight constraints of CubeSats,” the document added.

The Busek Company was selected to continue development of a low-impulse bit electrospray thruster control system with SBIR Phase II funding.

Busek’s “passive electrospray thruster control which will enable extremely fast thruster operations and thereby unprecedented minimum impulse bits,” the company said.

“Busek’s BET-300-P thruster is under active development as a precision reaction control system (RCS) which will provide orders of magnitude improvements over state-of-the-art alternative attitude control systems (ACS) for CubeSats/small-spacecraft,” the summary added.

NASA selected two proposals for funding that focus on communications technologies for distributed small spacecraft missions beyond low Earth orbit (LEO).

Blink Astro of Atlanta will continue development of a delay-tolerant radio for use in spacecraft operating in deep space.

“This solution has immediate applicability in enabling deep space communication or swarm constellation science missions,” the company said. “As NASA begins to more broadly adopt small satellites, the need for a small form factor, lower power, delay and disruption tolerant radio becomes paramount, especially as more novel mission concepts outside of Low Earth Orbit emerge.”

NASA also selected Fibertek of Herndon, Virginia to continue development of technologies

“This proposed SBIR will build on Fibertek’s NASA-funded Compact Laser Communications Terminal (CLCT) heritage to develop new ultra-low SWaP-c technology that can transform this unit into a Distributed Spacecraft Missions (DSM) capable laser communications terminal supporting small satellite intersatellite links (ISL) as well as deep space downlinks to Earth using relay satellites,” Fibertek said in its proposal summary.

Masten Space Systems of Mojave, California was selected for a SBIR Phase II award to continue development of technology that will improve the 3-D manufacturing of rocket engine injectors.

“Masten is currently focusing on the propulsion elements of PermiAM with direct applicability to small satellite launch vehicles, upper stage engines, and planetary landers in support of the NASA [Commercial Lunar Payload Services] program,” the company said in its proposal summary.

“For aviation it may be used to improve the performance and reliability of commercial jet engines. Current jet engine combustion chamber designs use bypass air and baffles to keep components from overheating,” the summary added. “PermiAM would allow the more even application of cooling air, better boundary layer performance, and damp instabilities. Masten is also selling PermiAM to other rocket engine manufacturers.”

Summaries of the six selected proposals follow.

Small Spacecraft Technologies
SBIR Phase II Awards

Alameda Applied Sciences Corporation
Oakland, CA

High-Impulse, Scalable, Metal Plasma Thruster for Cubesat Missions
Subtopic: Cubesat Propulsion Systems

Principal Investigator
Dr. Mahadevan Krishnan Ph.D.

Estimated Technology Readiness Level (TRL) :
Begin: 6
End: 9

Technical Abstract

The innovation in this SBIR project is the maturation of AASC’s TRL-4 Metal Plasma Thruster into a TRL-9 system that is fully flight qualified by a launch into space (June 2020), followed by commercial sales of multiple thruster systems to NASA and other satellite makers. This SBIR [Z8.01 Small Spacecraft Propulsion Systems] points out that although there are currently many technologies for propulsion systems, the miniaturization of these systems for small spacecraft is a particular challenge. While cold gas or pulsed plasma systems support small Δv applications, modules that can provide more demanding maneuvers still need development.

NASA seeks complete propulsion system solutions (thrusters, valves, propellant, sensors, electronics, etc.) capable of full-scale flight demonstration on 27U, 12U, 6U, or 3U CubeSats in support of deep space and/or swarm topology missions. Of particular interest are propulsion system solutions offering long life, reliability, and minimalistic use of CubeSat resources (power, energy, volume, and mass), while delivering propulsion capabilities that meet requirements.

AASC has met these goals with its innovative, electric propulsion thruster (MPT) that has no moving parts, uses solid propellant (non-toxic stable metals such as Mo, Nb, Pd and many others), is compact (fits into 3U CubeSats, and is modular, so scalable to 12U, 27U and even larger platforms. The simplicity of the system and relatively low manufacturing cost make the MPT highly attractive to the CubeSat market.

The technology has matured from TRL-4 to TRL-6 during the Ph-I effort. During Ph-II, we intend to take it to TRL-9 by launching into space and gathering operational data during positioning and attitude adjustment maneuvers on a 100kg satellite.

Potential NASA Applications

The MPT architecture lends itself to use on all NASA satellites in the 5 kg -250 kg category. Pathfinder (INSPIRE) is one example. The MPT could suit that mission, if a window of opportunity presents itself. NASA also plans to launch Lunar IceCube, a public-private partnership that will send a tiny CubeSat (Dec 2019) to do water-ice prospecting from an elliptical orbit around the moon. Lunar IceCube, Lunar Flashlight, BioSentinel and NEA Scout are part of a movement to employ cost-effective CubeSats for deep-space exploration.

Potential Non-NASA Applications

1000s of satellites (5 kg -80 kg) might soon be in LEO. Imaging satellites that today are launched into higher than 500km to avoid rapid burn-up, would offer higher resolution and faster refresh rates at lower altitudes but would need propulsion. The MPT (compact, no moving parts, solid fuel) is ideal for these satellites and in custom designed arrays, could be useful for larger satellites too.

Duration: 24 months

ExoTerra Resource, LLC
Littleton, CO

Modular Xenon Micro Electric Propulsion System
Subtopic: Cubesat Propulsion Systems

Principal Investigator
Michael VanWoerkom

Estimated Technology Readiness Level (TRL) :
Begin: 5
End: 6

Technical Abstract

While CubeSats have begun to disrupt the entire satellite industry, a lack of adequate propulsion options continues to limit their adoption beyond experimental missions. Rideshare restrictions to propulsion systems often limit CubeSats to the non-optimal orbits into which the primary mission delivers them, and leaves them unable to maintain their orbits. This curbs CubeSat adoption into commercial, persistent Earth science, or interplanetary missions.

ExoTerra’s Modular Xenon Micro Electric Propulsion System is a high-impulse propulsion system that enables CubeSats to alter or maintain their orbits and to perform affordable, targeted science missions throughout the inner solar system. The proposed integrated system provides 4-33 mN of thrust and 36-53 kNs of impulse at an Isp from 700-1500 s using a micro-Hall Effect Thruster, and can package in 9U of volume to meet the tight constraints of CubeSats.

Variations of the system can provide over 100 kN-s of impulse. The propulsion system consists of the Xenon propellant and distribution system, a high efficiency PPU that is radiation tolerant to 100 krad, the Halo thruster and a thrust vector controller.

Potential NASA Applications

Potential NASA applications include interplanetary CubeSat missions with a need for non-toxic, high impulse and thrust propulsion systems. With this capability, NASA can send CubeSat missions to the Moon, asteroids, comets, Venus, Lagrange points, or Mars. The scalability of the propellant system design makes it applicable for a wide range of spacecraft sizes and mission architectures.

Potential Non-NASA Applications

Exoterra’s Xenon Micro EP System provides orbit raising, inclination change and maintenance for commercial microsats. Commercial satellites can reach their working orbits using a smaller, simpler, and lower-cost SEP main propulsion system. The system can also be used in an SEP-based upper stage for the burgeoning small launch vehicle market, delivering microsats from LEO to GEO orbit or beyond.

Duration: 20 months

Busek Company, Inc.
Natick, MA

Low Impulse Bit Electrospray Thruster Control
Subtopic: Cubesat Propulsion Systems

Principal Investigator
Daniel Courtney

Estimated Technology Readiness Level (TRL) :
Begin: 4
End: 5

Technical Abstract

Busek proposes to develop a new form of passive electrospray thruster control which will enable extremely fast thruster operations and thereby unprecedented minimum impulse bits. Busek’s BET-300-P thruster is under active development as a precision reaction control system (RCS) which will provide orders of magnitude improvements over state-of-the-art alternative attitude control systems (ACS) for CubeSats/small-spacecraft.

The low inertia of CubeSats combined with vibrational disturbances and resolution limitations of state-of-the-art ACS presently limit precision body-pointing and position control. Busek’s electrospray thrusters aboard the ESA LISA Pathfinder (NASA ST-7) spacecraft, demonstrated control of a proof mass location to within ~2nm per root Hz over a wide band. The BET-300-P, enhanced by exploitation of its high-speed dynamic response in this program, seeks to extend that success to small spacecraft platforms.

Passively fed electrospray thrusters are highly compact, including fully integrated propellant supplies, and are capable of ~100nN thrust precision with 10’s of nN noise. Thrust can be accurately throttled over >150x, up to a scalable maximum of 10’s to 100’s of uN. While typically operated in largely continuous states they are unique in that emission can be electrically stopped/started at ms time scales. Thus, extremely low impulse bits may be achieved over very short durations.

In Phase I pulses as short as 1ms permitted throttling from <0.1uNs up to 100’s of uNs. These traits, combined with >750s specific impulse, and thereby low propellant mass could enable these systems to replace traditional reaction wheel ACS and high-propellant mass cold gas systems; enabling milliarcsec control authority for CubeSats versus the present arcsec level SOA.

Phase II will regimentally advance the technology by first performing detailed investigations of critical phenomena and then applying those results towards a rigorously tested engineering model thruster.

Potential NASA Applications

Ongoing NASA mission studies include the BET-300-P for attitude control, formation flight and positioning of small spacecraft. Specific benefiting applications include deep-space missions, astronomy, solar-system observations, laser communications and space situational awareness. Mission durations are extended by increased wheel desaturation capacity. Improved body pointing would augment stability; permitting lower cost/complexity realization of existing needs and enabling new objectives.

Potential Non-NASA Applications

High-precision small-sat propulsion systems are an enabling technology with numerous applications. The virtual elimination of vibrations while superseding reaction wheel precision is a competitive advantage. Precision pointing/positioning capabilities of the BET-300-P system are otherwise unavailable. Potential customers include international partners (eg ESA), the DoD and commercial EO missions.

Duration: 24 months

Blink Astro, LLC
Atlanta, GA

Delay-Tolerant Radio for Cooperative Groups of Small Spacecraft
Subtopic: Communications for Distributed Small Spacecraft Beyond LEO

Principal Investigator
Mr. Darshan Shah

Estimated Technology Readiness Level (TRL) :
Begin: 3
End: 4

Technical Abstract

Blink Astro, LLC proposes a Phase II SBIR development effort that includes prototyping the ION-DTN protocol on our Phase I downselected microcontroller, integrated radio design, and a final demo of 3 ION-DTN nodes simulating a real-world scenario. Creation of a market strategy and supporting marketing collateral materials will also be developed for the end product as it is being advanced from TRL 3 to TRL 4 at the conclusion of effort.

Potential NASA Applications

This solution has immediate applicability in enabling deep space communication or swarm constellation science missions. As NASA begins to more broadly adopt small satellites, the need for a small form factor, lower power, delay and disruption tolerant radio becomes paramount, especially as more novel mission concepts outside of Low Earth Orbit emerge. Blink’s ION-DTN Radio offers a cost-effective, turnkey solution to meeting DTN demands for future NASA missions and enables small satellite missions of greater scale and scientific return.

Potential Non-NASA Applications

Non-NASA commercial applications for the Blink® ION-DTN Radio range from real-time aircraft tracking to commercial LEO satellite constellations. Of particular interest to Blink®, is the near-term applicability of the ION-DTN Radio with its LEO satellite constellation for IoT connectivity.

Duration: 24 months

Fibertek, Inc.
Herndon, VA

Technologies Enabling Distributed Spacecraft Missions (DSM)
Subtitle: Communications for Distributed Small Spacecraft Beyond LEO

Principal Investigator
Mr. Nigel Martin

Estimated Technology Readiness Level (TRL) :
Begin: 4
End: 5

Technical Abstract

This proposed SBIR will build on Fibertek’s NASA-funded Compact Laser Communications Terminal (CLCT) heritage to develop new ultra-low SWaP-c technology that can transform this unit into a Distributed Spacecraft Missions (DSM) capable laser communications terminal supporting small satellite intersatellite links (ISL) as well as deep space downlinks to Earth using relay satellites. This approach leverages previous NASA and commercial investments in the CLCT and can enable mission adoption within the next 5 years.

This SBIR proposes to update the CLCT design for baseline DSM operational use to enable mesh networks by independently pointing three or more optical terminals on a single satellite and to develop a low SWaP serially concatenated pulse-position modulated (SCPPM

Potential NASA Applications

Fibertek is aligned with the NASA SCaN vision and has been working to develop end-to-end space optical communications link capabilities, such as High-Speed Optical Ground Station technology and SmallSat and CubeSat space optical terminal capabilities. Optical transceiver technology applies to ground and space nodes for sending and receiving information. This Phase II SBIR effort will enhance our offerings at both nodes of SCaN space optical communications links, and for NASA, SmallSat Science missions:

Potential Non-NASA Applications

All DoD services are interested in space optical communications because of data security, increased bandwidth, and robustness against jamming and interception. This Phase II modem development activity aligns with products for this market as well. Fibertek is currently pursuing, with partners, the opportunity to provide exactly this type of modem capability on an AFRL Program for 2019.

Duration: 24

Masten Space Systems, Inc.
Mojave, Calif.

PermiAM: Engineered Porosity In-Situ with Fully Dense AM Structure
Subtopic Title: Small Launch Vehicle Technologies and Demonstrations

Principal Investigator
Matthew Kuhns

Estimated Technology Readiness Level (TRL):
Begin: 5
End: 6

Technical Abstract

This work answers the questions and needs of Focus Area 21 Subtopic Z9.01 for small launch vehicle technologies by providing affordable launch architecture, as propulsion systems are the highest cost subsystem for rocket development and PermiAM will enable a large savings for main propulsion system engine development.

PermiAM will enable increased design simplicity for AM injectors and reduced development costs through improved face cooling and improved combustion stability. Phase I demonstrated successful use of PermiAM in multiple materials for rocket engine injectors. A full scale proof of concept ground test will be demonstrated by the end of Phase II.

Potential NASA Applications

PermiAM material is aligned with NASA Technology Roadmap needs TA1.2, TA2.1, and TA12. Masten is currently focusing on the propulsion elements of PermiAM with direct applicability to small satellite launch vehicles, upper stage engines, and planetary landers in support of the NASA CLPS program. For SLS, the RS-25 and RL10 use a coaxial injector with Rigimesh face. As AM build volumes increase it will be possible to replace the expensive and complex rigimesh injector with an AM version to lower the cost of heavy lift space access.

Potential Non-NASA Applications

For aviation it may be used to improve the performance and reliability of commercial jet engines. Current jet engine combustion chamber designs use bypass air and baffles to keep components from overheating. PermiAM would allow the more even application of cooling air, better boundary layer performance, and damp instabilities. Masten is also selling PermiAM to other rocket engine manufacturers.

Duration: 12 months