DellingrX Small Satellite Spacecraft Bus Architecture

NASA's newly developed antenna is lightweight (at or below 2 grams), low volume (at or below 1.2 cm3), and low stowage thickness (approx. 0.7 mm), all while delivering high performance (at or above 10 dBi gain). The antenna includes a novel design-material combination in a helical coil conformation. The design allows the antenna to compress for stowage (e.g., satellite launch), then self-deploy at the desired time in orbit. NASA's lightweight, self-deployable helical antenna can be integrated into a thin-film solar array (or other large deployable structures). Integrating antenna elements into deployable structures such as power generation arrays allows spacecraft designers to maximize the inherently limited resources (e.g., mass, volume, surface area) available in a small spacecraft. When used as a standalone (i.e., single antenna) setup, the the invention offers moderate advantages in terms of stowage thickness, volume, and mass. However, in applications that require antenna arrays, these advantages become multiplicative, resulting in the system offering the same or higher data rate performance while possessing a significantly reduced form factor. Prototypes of NASA's self-deployable, helical antenna have been fabricated in S-band, X-band, and Ka-band, all of which exhibited high performance. The antenna may find application in SmallSat communications (in deep space and LEO), as well as cases where low mass and stowage volume are valued and high antenna gain is required.

SmallSat Standardized Architecture is architecture that is modularized, pressurizable, thermally controlled spacecraft-designed to host ruggedized commercial off-the-shelf (COTS) instrumentation in a terrestrial-like environment on orbit. The architecture takes advantage of a pressurizable volume for both spacecraft and payload systems. The pressurizable volume provides multiple benefits, primarily in thermal design. By maintaining one atmosphere of pressure inside the SmallSat, materials that might otherwise outgas and/or fail and/or cause significant contamination issues, are no longer a concern. This also means that certain vibration-absorbing materials/designs used in COTS hardware can be used on orbit. Additionally, printed circuit boards do not have to be redesigned for thermal requirements, plus conformal coating and contamination bake-outs are no longer required. The SmallSat architecture is designed to take advantage of the United States Air Force (USAF) Rideshare Program and the Evolved Expendable Launch Vehicle Secondary Payload Adaptor (ESPA) ring. The ESPA ring comes in two sizes: standard and Grande. The architecture has two main configurations, one designed for the ESPA Grande, and the other for the standard ESPA ring. The ESPA Grande version is a hockey-puck-shaped spacecraft bus measuring approximately 40 inches in diameter and 20 inches in height. This version takes full advantage of the ESPA Grande’s 300-kilogram capability per attachment point.

SmallSat designers seek to employ restraints and release mechanisms of minimal size and weight, often placing each on the outside of the SmallSat structure. Surprisingly, "fishing line" (released via burn through) is often used to secure and release deployables. Vibrations and forces generated during launch can stretch the fishing line, thus allowing these precious deployables to become damaged or otherwise not release properly later on. While these small sats are less expensive than their larger counterparts, satellite owners must minimize the chance that deployables are damaged or that deployment is unsuccessful. Five years ago, engineers at NASA GSFC faced these SmallSat deployment challenges and knew a better way must exist to prevent equipment damage and ensure successful release. Investigating a host of designs to minimize size, weight, and cost while maximizing communication and mechanical reliability, NASA's engineers created DANY (the Diminutive Assembly for Nanosatellite deploYables). NASA's DANY technology uses spring-loaded metal pins, a reliable burn-through mechanism, efficient bracketing, and a circuit board - all within a 3.0" x 1.3" x 0.2" volume (smaller than a stack of 10 business cards) - to reliably stow and release deployables on command. Using DANY, stowed deployables are securely fastened using the spring-loaded locking pins. Upon receiving a deployment signal, a plastic restraining link is burned through which allows the spring-loaded pins to release the deployable and simultaneously trigger a switch to signal a successful deployment event.

NASA's SpaceCube Mini SSDR is a 3.5”x3.5” card designed for use in CubeSats and SmallSats. The SSDR uses a radiation-tolerant field programmable gate array (FPGA) that interfaces with two independently controlled and powered banks of NAND Flash storage, providing up to 12 Terabits of storage capacity. The card includes multiple SpaceWire nodes and multi-gigabit transceivers for commanding and data transfer, various error prevention and correction mechanisms including Reed-Solomon encoding/decoding and data randomization schemes, and depacketizers/packetizers for handling data in CCSDS format. This NASA technology is innovative in its combination of high reliability for harsh radiation environments (e.g., geostationary orbit, lunar orbit and surface, etc.) with high-speed data transfer capabilities (400+ MB/s write, 600+ MB/s read) in a compact form factor. The design allows for selective population of NAND Flash modules and independent control of memory banks, enabling power optimization through features like single-bank operation. The card integrates with a modular architecture system in which multiple CubeSat-sized cards (e.g., processors, GPS, etc.) can be mixed and matched to meet specific mission requirements. The SSDR card includes radiation-hardened voltage regulators to ensure safe operation in space environments. The SSDR is ideal for small form factor satellites with some combination of the following requirements: (a) ability to store large amounts of data generated by high-performance detectors and sensors for extended durations (e.g., in environments without nearby relay capabilities), (b) ability to read and write data with high throughput, and (c) ability to operate in harsh radiation environments. It is fully compatible with NASA’s CubeSat Card Specification (CS2) and NASA’s SpaceCube v3.0 mini processing card, which is also available for licensing.

NASA’s High Propellant Throughput Small Spacecraft Electric Propulsion thruster offers a propellant throughput capability of greater than 120 kg with a nominal thruster efficiency greater than 50%. The new thruster design combines heritage Hall thruster component design approaches with recent NASA GRC advancements in the areas of advanced magnetic circuit design, robust propellant manifolds, and center mounted cathodes. Prototypes of the High Propellant Throughput Small Spacecraft Electric Propulsion thruster have been fabricated and proof-of-concept has been demonstrated. A significant advancement in the High Propellant Throughput Small Spacecraft Electric Propulsion thruster is NASA's optimized magnetically shielded (OMS) field topology. The new OMS configuration reduces discharge channel erosion rates compared to conventional Hall thrusters, while reducing front pole cover erosion rates compared to traditional magnetically shielded Hall thrusters. This system also includes a largely unibody structure to reduce fabrication cost, increase strength, and optimize thermal management. A coupling plate between the high voltage discharge channel and low voltage thruster body allows more efficient thruster assembly and verification processes. Other design advancements further simplify assembly, improve robustness, and optimize performance.