Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase I | Award Amount: 150.00K | Year: 2015
ABSTRACT: Busek proposes to develop an ultra compact CubeSat propulsion system utilizing non-toxic, green monopropellant. The system will occupy 1/2U volume and the tuna can protrusion space made available by a 3U CubeSat launchers ejector spring. Key components of this concept include an innovative micro thruster based on Buseks groundbreaking monopropellant catalyst technology, a material-compatible propellant tank, and a highly miniaturized feed system. The proposed system will provide total impulse on the order of 580N-sec, which will give a 3U/4kg CubeSat approximately 150m/s of delta-V maneuverability. The thruster and the feed system are expected to require less than 10W power to operate. Phase I will focus on risk reduction efforts by developing critical components such as the micro thruster and the high-capacity tank. Phase II will focus on advancing the system design and complete hardware development, which will include full characterization and life testing of the micro thruster. BENEFIT: A 1/2U green monopropellant system with high total impulse (>500N-sec) is unique within the industry and of significant interest to DoD, civil, and commercial customers alike. In the CubeSat propulsion world, the proposed micro thruster has a niche as it can provide smooth and steady thrust, whereas other similar systems on the market may be too powerful for CubeSats to steer. Current CubeSats situated in LEO have useful life anywhere between 3 and 6 months; using the proposed propulsion system for drag makeup can potentially extend mission life to well beyond 12 months. Prolonged life of assets in orbit will significantly alter the economics of any space-centric entity, whether public or private. The non-toxic nature of the propellant further reduces CubeSat costs associated with development, integration and launch preparation.
Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 750.00K | Year: 2015
ABSTRACT: Busek Co. Inc. proposes to develop a high power, low-mass Hall effect thruster. The baseline thruster is sized at nominally 8kW power level. A specific feature to be implemented includes the use of SmCo permanent magnets. The goal of the effort is to reduce thruster specific mass to 60%. In Phase I Busek evaluated an existing permanent magnet thruster to develop the theoretical and experimental underpinnings of the full power design. Following the experimental effort Busek prepared the detailed engineering design of the thruster designated BHT-8000-PM. The thruster design was supported by magnetic modeling, lifetime predications, and thermal and structural analysis. In Phase II Busek will perform functional, performance and plume testing of the prototype thruster. Using the lessons learned from the prototype thruster development, Busek will design, build and environmentally and performance test an advanced version of the thruster with a center-mounted cathode to raise the maturity level to TRL 6. BENEFIT: The DoD has recently begun an effort to understand the potential of high-power EP for national assets such as AEHF, GPS, WGS, SBIRS, and reconnaissance satellites. Equipping assets with full EP for both orbit transfer and station keeping would allow dual-manifest launches and LEO injections in the majority of cases, saving hundreds of millions of dollars across constellations. In the case of the Space Missile Command (SMC) fleet, EP would allow dual-manifest LEO launches to occur, saving ~15% of the fleet-wide budget which includes the procurement, launch, and operation. The commercial industry is already transitioning to all-electric satellites to perform both orbit raising and station keeping. These include domestic satellite manufacturers Boeing (presently operating L-3 ion engines), Lockheed-Martin, Orbital Sciences and Space Systems/Loral, Between 2020 and 2022, 45 satellite orders are expected to launch having payload power at or near 14 kW, with 18 of these at or above 14 kW. This trend of higher power coincides with advancements in solar array technologies. Present state of the art arrays average 40 W/kg, whereas next generation arrays performance >10 W/kg.
Agency: Department of Defense | Branch: Air Force | Program: STTR | Phase: Phase II | Award Amount: 847.96K | Year: 2014
ABSTRACT: Busek Co. Inc. and Massachusetts Institute of Technology (MIT) propose to explore the physical limits of ionic liquid propulsion via development of new theory to explain effects of close packing emission density and to predict performance limits. The research is motivated by observations and tests demonstrating that emission from 2-dimensional porous surfaces yields order of magnitude greater emission densities than state-of-the-art MEMS approaches, and also that the emission densities, specific impulse, thrust, and charge/mass do not behave as expected or would be predicted by current electrospray theory. It is postulated that this is due to the changing nature of the emitter surface itself as propellant flowrates vary, and that emission unconstrained by fixed individual extractor apertures promotes more natural and free formation of emission sites at varying densities dictated by instantaneous operating conditions. For the Phase I effort, Busek and MIT developed theory describing porous emission from large 2-dimension surfaces and used available data and additional testing to confirm validity of the theory. These finding predicted performance limits of the 2-D surface emission phenomena. The Phase II shall use the theoretical predictions to develop novel prototype emitters to confirm the theory and attain ultra high-density ion emission. BENEFIT: The continual challenge of realizing the benefit of electrospray-based propulsion has been scale-up of thrust to the levels relevant and desired for most missions. With individual emitters producing thrusts commonly less than several microNewtons, and more usually only at the nanoNewton level, large scale multiplexing is required to achieve milliNewton thrust levels and beyond. Because of this, MEMS emitter architectures have been assiduously investigated owing to their capacity to generate large and densely-packed arrays of emitters. To-date, the MEMS approach has demonstrated some significant outcomes, but faces two difficulties for practical implementation: 1) The individual ballasting of emitters to dedicated extractor apertures greatly increases propensity for thruster failure due to shorting, and 2) MEMS process itself may limit emitter density due to microfabrication resolution constraints. 2-dimension surface emission has already demonstrated significantly superior emission densities and operating lifetimes than MEMS approaches based upon the strength of 2 basic concepts- that emitting from a 2-D surface dispenses with the failure-prone extractor that essentially masks much of the emission area, and that emission from a free surface, rather than predetermined sites, promotes natural formation of much greater number of emission sites. Preliminary data have already demonstrated the advantages of the 2-D approach, and the improved understanding enabled by the proposed research is expected to advance the understanding and develop predictive theory for development of extremely dense ion generation.
Agency: National Aeronautics and Space Administration | Branch: | Program: SBIR | Phase: Phase II | Award Amount: 749.98K | Year: 2016
Busek Co. Inc. proposes to advance the maturity of an innovative Spacecraft on Umbilical Line (SOUL) System suitable for a wide variety of applications of interest to NASA, DoD and commercial missions. SOUL is a small (
Agency: National Aeronautics and Space Administration | Branch: | Program: SBIR | Phase: Phase II | Award Amount: 749.90K | Year: 2016
Busek is developing an advanced iodine feed system for Hall Effect Thrusters (HETs), ion engines, cathodes, and other plasma generators. The feed system features an innovative piezo driven valve that saves volume, mass, cost, and energy with respect to state of the art alternatives. The feed system also features a low mass plastic propellant tank that may be manufactured through additive processes. This allows low cost, complex shapes that can maximize the use of available space inside volume-restricted spacecraft. The feed system will be especially attractive for small spacecraft and CubeSats. Iodine stores as a solid and sublimates at modest temperatures as the molecule I2, which allows many benefits with respect to traditional Hall effect thruster fuels such as xenon and krypton. These advantages include higher storage density, lower storage pressure, the ability to test high power systems at space-relevant conditions in modest facilities, the capability to store propellant in space without active regulation, and the capacity to transfer propellant at low-pressure conditions in space. In a space-limited spacecraft, using iodine instead of state of the art xenon could increase available delta-V by a factor of three (3) or more. In Phase I, Busek developed a feed system featuring the advanced components, which was integrated into the iSAT spacecraft form factor. The system was then tested with an iodine compatible Hall effect thruster in relevant space conditions. In Phase II, an improved feed system will be designed, built and tested. Major Phase II technical objectives include developing an engineering model iodine resistant, piezo driven flow control valve, finalizing the feed system control architecture, identifying and evaluate commercial components to fill out the system, and building and characterizing the system. At the conclusion of the Phase II effort, engineering model valves will be delivered to NASA for further characterization.