CubeSat Propulsion and Maneuvering System
Propulsion
CubeSat Propulsion and Maneuvering System (MSC-TOPS-155)
Flight qualified components minimize cost and schedule, maximize performance
Overview
NASA Johnson Space Center’s R5 Project Team has developed a modular CubeSat platform series, called “R5-SX”, whose six-degree-of-freedom cold-gas propulsion and maneuvering system employs three mainstay innovations: a High-Pressure Manifold, a Thruster Pod, and Threaded Jet Inserts. Their technical descriptions can be found below.
The SX-series platform was developed to significantly reduce costs associated with payload demonstration in Low Earth Orbit (LEO) by implementing a minimally-viable product approach to component scope definition without sacrificing performance. Although aligned with on-orbit mission abilities, these individual propulsion and maneuvering innovations may also translate to terrestrial applications that utilize, or desire, metered pressurized fluid-flow.
The High-Pressure Manifold, Thruster Pod, and Threaded Jet Inserts are at technology readiness level (TRL) 8 (actual system completed and "flight qualified" through test and demonstration). Please note that NASA does not manufacture products itself for commercial sale.
SHOWN ABOVE: The R5 Spacecraft 2, (R5-S2), and the R5 Spacecraft 4, (R5-S4), are the first two R5 spacecraft to successfully make it into orbit. These spacecraft, which contain no space-rated components, quickly exceeded their minimum mission success criteria and operated throughout their 10-month mission lifetime in orbit.
The Technology
Starting with a "clean sheet" for process and system design, the R5 Project Team charted a path, subsystem by subsystem, through commercial, industrial, automotive, and medical-grade components, to arrive at a functional baseline CubeSat (SX-series) bus. Although the R5 approach leans heavily on commercial-off-the-shelf (COTS) hardware, there are instances where NASA custom-designed components have been determined to be the less expensive and faster-to-develop option. Such is the case for the SX cold-gas propulsion and maneuvering system’s High-Pressure Manifold, Thruster Pod, and Threaded Jet Inserts.
The High-Pressure Manifold (MSC-27997-1) is a ported fluid distribution manifold that, relative to the SX-series CubeSat, distributes pressurized cold-gas to each Thruster Pod. Machined from high-grade aluminum, the SX-series manifold has a Maximum Design Pressure (MDP) of 3000 psig. The R5 team designed the manifold to accept a fuel tank, regulator, isolation valve, relief valve, transducer, and other COTS high-pressure fittings.
There are four component Thruster Pods (MSC-27996-1) per each SX-series CubeSat, and each Thruster Pod is fed pressurized cold-gas from the High-Pressure Manifold. These pods are designed to be 3D-printed using additively-manufactured aluminum and are later machined to add female threads for the Threaded Jet Inserts, heli-coils, and valve ports. Each pod comprises three integrated propellant conduits that independently feed the Threaded Jet Inserts. Each directional jet has an assigned thruster valve, mounted to the Thruster Pod, which throttles the pressurized cold-gas for CubeSat propulsion and maneuvering about three linear and three rotational axes.
Finally, the Threaded Jet Insert (MSC-27994-1) embodies a set-screw form factor, and relative to the SX-series CubeSat, threads into the outward-facing end of each Thruster Pod propellant conduit. Each jet is laser machined and employs an internal flow-through micro-nozzle to accelerate escaping gas fed from the thruster valve to produce thrust.
These SX-series propulsion system innovations for R5 CubeSats may also have terrestrial applications across multiple industries where, for example, targeted high-velocity gas bursts, precise pneumatic micro-force, or modular choked-flow gas metering are required.
Benefits
- Flight-qualified technology
- Tunable architecture yields pressure/flow metering applications across multiple industries
- Components together facilitate a six degree-of-freedom cold-gas propulsion and maneuvering system
- High-Pressure Manifold features 3000 psig maximum design pressure and accommodates COTS subcomponents
- 3D-printed Thruster Pod comprises three-axis thruster ports for thrust metering via the Threaded Jet Inserts
- Threaded Jet Insert features a set-screw form-factor with a tunable internal micro-nozzle
- Intended component shirt-sleeve build environment minimizes schedule duration and dependency for LEO demonstration
- Components facilitate quick-to-flight CubeSat builds for responsive payloads
- Features minimal approach philosophy to speed assembly and integration
Applications
- System Aerospace: CubeSat propulsion and maneuvering for payload demonstrations; servicing and inspection of vehicles in LEO; commercial satellite life-extension platforms; active space debris removal tugs
- System Terrestrial: air-bearing orbital simulation testbeds; pneumatic actuation in spark-hazardous environments; UAV loss-of-control and emergency recovery
- High-Pressure Manifold Terrestrial: alternative fuel system distribution block such as hydrogen fuel cell or CNG; rapid inflatables and life support, high-pressure emergency gas deployment
- Thruster Pod Terrestrial: UAV and drone stabilization, cold-gas reaction control system; industrial automation and soft robotics; automated pneumatic sorting systems
- Threaded Jet Insert Terrestrial: Semiconductor and optics manufacturing, micro-jet gas bursts for cleaning; Precision metering and spray coating, quick-swap metering orifices for lab gas-calibration equipment, atomization nozzles
Technology Details
Propulsion
MSC-TOPS-155
MSC-27994-1
Patent Pending
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