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NASA's System for In-situ Defect (e.g., porosity, fiber waviness) Detection in Composites During Cure consists of an ultrasonic portable automated C-Scan system with an attached ultrasonic contact probe. This scanner is placed inside of an insulated vessel that protects the temperature-sensitive components of the scanner. A liquid nitrogen cooling systems keeps the interior of the vessel below 38°C. A motorized X-Y raster scanner is mounted inside an unsealed cooling container made of porous insulation boards with a cantilever scanning arm protruding out of the cooling container through a slot. The cooling container that houses the X-Y raster scanner is periodically cooled using a liquid nitrogen (LN2) delivery system. Flexible bellows in the slot opening of the box minimize heat transfer between the box and the external autoclave environment. The box and scanning arm are located on a precision cast tool plate. A thin layer of ultrasonic couplant is placed between the transducer and the tool plate. The composite parts are vacuum bagged on the other side of the tool plate and inspected. The scanning system inside of the vessel is connected to the controller outside of the autoclave. The system can provide A-scan, B-scan, and C-scan images of the composite panel at multiple times during the cure process. The in-situ system provides higher resolution data to find, characterize, and track defects during cure better than other cure monitoring techniques. In addition, this system also shows the through-thickness location of any composite manufacturing defects during cure with real-time localization and tracking. This has been demonstrated for both intentionally introduced porosity (i.e., trapped during layup) as well processing induced porosity (e.g., resulting from uneven pressure distribution on a part). The technology can be used as a non-destructive evaluation system when making composite parts in in an oven or an autoclave, including thermosets, thermoplastics, composite laminates, high-temperature resins, and ceramics.

Ultrasonic Stir Welding is a solid state stir welding process, meaning that the weld work piece does not melt during the welding process. The process uses a stir rod to stir the plasticized abutting surfaces of two pieces of metallic alloy that forms the weld joint. Heating is done using a specially designed induction coil. The control system has the capability to pulse the high-power ultrasonic (HPU) energy of the stir rod on and off at different rates from 1-second pulses to 60-millisecond pulses. This pulsing capability allows the stir rod to act as a mechanical device (moving and stirring plasticized nugget material) when the HPU energy is off, and allowing the energized stir rod to transfer HPU energy into the weld nugget (to reduce forces, increase stir rod life, etc.) when the HPU energy is on. The process can be used to join high-melting-temperature alloys such as titanium, Inconel, and steel.

The plasma system consists of a glass tube with a diameter of 0.5 mm or larger, if desired. The electrodes are separated by 10 mm. Helium, argon or cold dry air can be used as a plasma gas source. An applied high voltage between the electrodes causes the gas to breakdown within the central core of the glass capillary generating atmospheric plasma. Nanostructures colloids/organic/inorganic precursors are placed in a glass container with an inlet and outlet for carrier gas and are seated on an ultrasonic nebuliser. The aerosol is then carried into the plasma stream by the carrier gas and is deposited. The atmospheric plasma deposition system can be modified for depositing multiple materials, either simultaneously or sequentially, and for high-throughput processing by having multiple jets. Each capillary can either be connected to the container containing a single precursor material or to different containers containing different precursor materials to facilitate multiple depositions. The multi-jet plasma system can be automated and controlled individually to precisely control surface characteristics. This technique is independent of the chosen substrate, and has proven to work for many substrates, including paper, plastic, semiconductors and metals.

Going farther, faster and hotter in space means innovating how NASA constructs the materials used for heat shields. For HEEET, this results in the use of dual-layer, three-dimensional, woven materials capable of reducing entry loads and lowering the mass of heat shields by up to 40%. The outer layer, exposed to a harsh environment during atmospheric entry, consists of a fine, dense weave using carbon yarns. The inner layer is a low-density, thermally insulating weave consisting of a special yarn that blends together carbon and flame-resistant phenolic materials. Heat shield designers can adjust the thickness of the inner layer to keep temperatures low enough to protect against the extreme heat of entering an atmosphere, allowing the heat shield to be bonded onto the structure of the spacecraft itself. The outer and inner layers are woven together in three dimensions, mechanically interlocking them so they cannot come apart. To create this material, manufacturers employ a 3-D weaving process that is similar to that used to weave a 2-D cloth or a rug. For HEEET, computer-controlled looms precisely place the yarns to make this kind of complex three-dimensional weave possible. The materials are woven into flat panels that are formed to fit the shape of the capsule forebody. Then the panels are infused with a low-density version of phenolic material that holds the yarns together and fills the space between them in the weave, resulting in a sturdy final structure. As the size of each finished piece of HEEET material is limited by the size of the loom used to weave the material, the HEEET heat shield is made out of a series of tiles. At the points where each tile connects, the gaps are filled through inventive designs to bond the tiles together.

Modular Artificial-Gravity Orbital Refinery Spacecraft is a solution for refining in-situ materials collected in space, such as from asteroids and Mars moons, as well as recycling spacecraft debris, while orbiting in micro-gravity conditions. The spacecraft is coupled with refining modules for refining and recycling different types of materials. It generates artificial gravity for operation in low-gravity environments. The spacecraft is comprised of rotating rings, each generating artificial gravity and angular momentum. When the rotating rings are combined on the spacecraft platform, however, they have a net near-zero angular momentum such that the spacecraft can change its attitude with minimal propellant or rotate at the rate of the object the spacecraft platform is attached to. The spacecraft platform can self-balance to accommodate different sized modules and modules with moving loads. The refined and recycled materials can be used to create products in-situ as well as products too large to launch from Earth, such as construction of orbiting space habitats, large spacecraft, solar-power stations, and observatories.

The technology is a method to increase automation of Additive Manufacturing (AM) through augmentation of the Fused Filament Fabrication (FFF) process. It can significantly increase the speed of 3D printing by automating the removal of printed components from the build platform without the need for additional hardware, which increases printing throughput. The method can also be leveraged to perform automated object testing and characterization. The method includes embedding into the manufacturing instructions methods to fabricate directly onto the build platform an actuator tool, such as a linear spring. The deposition head can be leveraged as a robotic manipulator of the actuator tool to bend, cock, and release the linear spring to strike the target manufactured object and move it off the build platform of the machine they were manufactured on. The ability for an object to 'fly off of the machine that made it' essentially enables automated clearing of the processed build volume. The technology can also be used for testing the AM machine or the feedstock material by successively fabricating prototypes of the manufactured object, and taking measurements from sensors as the actuator strikes the prototype. This provides automated testing for quality control, machine calibration, material origins, and counterfeit detection.

To overcome the challenges of conventional molding, researchers at NASA Glenn have developed a rapid prototyping approach for three-dimensional printing of polymer aerogels using deposition into a viscous, sacrificial support medium. The sacrificial support stabilizes the aerogel deposition, allowing precise layer-by-layer construction of self-supporting aerogel networks that would otherwise be unprintable in air. Following printing and gelation of the polymer network, the printed structure is gently removed from the sacrificial medium, yielding a freestanding aerogel precursor with high shape fidelity. This method decouples printability from intrinsic material viscosity and enables rapid iteration of aerogel geometries, offering a scalable pathway for additive manufacturing of ultra-lightweight, architected polymer aerogels with tailored geometries, while retaining microstructural, mechanical, and thermal properties. The method involves: 1. Forming a solution comprised of a polymer precursor, cross-linker, solvent, and catalyst to create a dilute polymer solution. 2. 3D printing the polymer precursor directly into the sacrificial support medium. 3. Following printing and network formation, the structure is removed from the sacrificial medium through a low-stress extraction process, yielding a freestanding polymer aerogel precursor that retains the as-printed geometry with high fidelity. The sacrificial medium functions as a temporary, conformal support matrix that stabilizes each deposited droplet or filament in situ, enabling freeform construction of aerogel. This strategy enables the fabrication of highly porous, interconnected networks with controlled feature resolution across multiple length scales, while maintaining the intrinsic low density and high surface area required for aerogel performance.

Traditional aerogels are produced by sol-gel chemistry where a dilute polymer solution is taken to gelation. Polymer Aerogel 3D printing requires a high viscosity sol for stackable extrusion; however, this limits the time frame to print the materials prior to gelation. In response to this issue, NASA researchers have developed a novel dual solvent process to be used in additive manufacturing (3D printing). A dual-solvent formulation is employed during polymer aerogel precursor preparation to enable 3D printing of self-supporting structures. The system combines a high–boiling point aprotic solvent, which supports polymerization and network formation during aerogel synthesis, with a secondary low–boiling point solvent that partially evaporates during extrusion and printing. Preferential evaporation of the low–boiling component increases the local solids concentration and material viscosity at the nozzle and immediately after deposition, enabling filament stackability and shape retention without premature gelation. This approach decouples printability from bulk gel chemistry, allowing precise control of rheology during printing while preserving the desired aerogel microstructure and porosity after drying. A Two-Pot System: • Pot 1 contains a cross-linked polyamic acid solution and acetic anhydride or water scavenger, dissolved into a mix of high and low boiling point solvents (e.g., Dimethyl Sulfoxide (DMSO), n-methylpyrrolidone (NMP), or Dimethylformadie (DMF), with acetone or tetrahydrofuran (THF), ethanol, or methanol. • Pot 2 contains a base catalyst (e.g., trimethylamine or pyridine) and optionally a thickening agent (e.g., polyvinyl alcohol or polyvinyl acetate) to match viscosities. Dual-Solvent Chemistry: The low boiling point solvent evaporates rapidly upon extrusion, increasing the polymer concentration and viscosity, allowing the aerogel to retain its shape and gel quickly. • Additive Manufacturing Process: The two solutions are mixed at the extrusion tip of a syringe/nozzle-based 3D printer. This enables low-viscosity flow pre-extrusion and rapid solidification post-extrusion—solving a key challenge in 3D printing aerogels.

Fabrication of NASA's pupil mask begins with the preparation of a silicon wafer, which serves as the foundation for the black silicon structure. The wafer undergoes ion beam figuring (IBF), a non-contact technique that precisely removes surface irregularities at the nanometer scale. This process ensures that the silicon surface is diffraction-limited, eliminating errors that could degrade optical performance. Once the wafer is polished to the required precision, it is then processed lithographically to define the mask pattern, creating reflective and absorptive regions essential for controlling light propagation. To achieve the desired high absorption characteristics, the lithographically patterned wafer undergoes cryogenic etching, a sophisticated process that transforms the silicon surface into a highly textured, black silicon structure. This method utilizes a controlled plasma environment with sulfur hexafluoride (SF6) and oxygen to etch the surface at cryogenic temperatures. The process is carefully optimized by adjusting parameters such as gas flow rates, chamber pressure, ion density, and etch duration, leading to the formation of high-aspect-ratio nanostructures on the silicon substrate. These structures, resembling a dense “forest” of silicon nanospikes, trap and diffuse incoming light, drastically reducing specular reflection. The resulting surface exhibits an ultra-low reflectivity that is orders of magnitude lower than conventional polished silicon. By leveraging NASA’s cutting-edge fabrication technique, the newly developed black silicon pupil mask offers a powerful solution for high-contrast astronomical imaging. Its ability to minimize scattered light and enhance optical contrast makes it an ideal component for space telescopes tasked with directly imaging exoplanets as well as other applications requiring ultra low reflectivity systems.