Results for “MOLD” — Page 70

NASA NTRS2009

Lunar Regolith Excavation Competition

The Lunar Regolith Excavation Competition is a new competition that needs graphics, logos, rules, as well as an arena. Although this is the first year of the competition, the competition is modeled after an existing competition, the Centennial Lunar Excavator Challenge. This competition however is aimed at college students. This makes the challenge identifying key aspects of the original competition and modeling them to fit into an easier task, and creating exciting advertisement that helps encourage participation. By using a youth focus group, young insight, as well as guiding advice from experts in the field, hopefully an arena can be designed and built, rules can be molded and created to fit, and alluring graphics can be printed to bring about a successful first year of the Lunar Regolith Excavation Competition.

Liles, Cassandra↗

NASA NTRS2013

Spacecraft Crew Cabin Condensation Control

A report discusses a new technique to prevent condensation on the cabin walls of manned spacecraft exposed to the cold environment of space, as such condensation could lead to free water in the cabin. This could facilitate the growth of mold and bacteria, and could lead to oxidation and weakening of the cabin wall. This condensation control technique employs a passive method that uses spacecraft waste heat as the primary wallheating mechanism. A network of heat pipes is bonded to the crew cabin pressure vessel, as well as the pipes to each other, in order to provide for efficient heat transfer to the cabin walls and from one heat pipe to another. When properly sized, the heat-pipe network can maintain the crew cabin walls at a nearly uniform temperature. It can also accept and distribute spacecraft waste heat to maintain the pressure vessel above dew point.

Carrillo, Laurie Y.↗

NASA NTRS2013

Surface Inspection Tool for Optical Detection of Surface Defects

The Space Shuttle Orbiter windows were damaged both by micrometeor impacts and by handling, and required careful inspection before they could be reused. The launch commit criteria required that no defect be deeper than a critical depth. The shuttle program used a refocus microscope to perform a quick pass/fail determination, and then followed up with mold impressions to better quantify any defect. However, the refocus microscope is slow and tedious to use due to its limited field of view, only focusing on one small area of glass at a time. Additionally, the unit is bulky and unable to be used in areas with tight access, such as defects near the window frame or on the glass inside the Orbiter due to interference with the dashboard. The surface inspection tool is a low-profile handheld instrument that provides two digital video images on a computer for monitoring surface defects. The first image is a wide-angle view to assist the user in locating defects. The second provides an enlarged view of a defect centered in the window of the first image. The focus is adjustable for each of the images. However, the enlarged view was designed to have a focal plane with a short depth. This allows the user to get a feel for the depth of different parts of the defect under inspection as the focus control is varied. A light source is also provided to illuminate the defect, precluding the need for separate lighting tools. The software provides many controls to adjust image quality, along with the ability to zoom digitally the images and to capture and store them for later processing.

Nurge, Mark↗

NASA NTRS2012

Resin Systems and Chemistry-Degradation Mechanisms and Durability in Long-Term Durability of Polymeric Matrix Composites

In choosing a polymer-matrix composite material for a particular application, a number of factors need to be weighed. Among these are mechanical requirements, fabrication method (e.g. press-molding, resin infusion, filament winding, tape layup), and use conditions. Primary among the environmental exposures encountered in aerospace structures are moisture and elevated temperatures, but certain applications may require resistance to other fluids and solvents, alkaline agents, thermal cycling, radiation, or rapid, localized heating (for example, lightning strike). In this chapter, the main classes of polymer resin systems found in aerospace composites will be discussed. Within each class, their responses to environmental factors and the associated degradation mechanisms will be reviewed.

Hinkley, Jeffrey A.↗

NASA NTRS2012

Regolith Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

This NIAC project investigated an innovative approach to provide heat shield protection to spacecraft after launch and prior to each EDL thus potentially realizing significant launch mass savings. Heat shields fabricated in situ can provide a thermal-protection system for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Regolith has extremely good insulating properties and the silicates it contains can be used in the fabrication and molding of thermal-protection materials. Such in situ developed heat shields have been suggested before by Lewis. Prior research efforts have shown that regolith properties can be compatible with very-high temperature resistance. Our project team is highly experienced in regolith processing and thermal protection systems (TPS). Routine access to space and return from any planetary surface requires dealing with heat loads experienced by the spacecraft during reentry. Our team addresses some of the key issues with the EDL of human-scale missions through a highly innovative investigation of heat shields that can be fabricated in space by using local resources on asteroids and moons. Most space missions are one-way trips, dedicated to placing an asset in space for economical or scientific gain. However, for human missions, a very-reliable heat-shield system is necessary to protect the crew from the intense heat experienced at very high entry velocities of approximately 11 km/s at approximately Mach 33 (Apollo). For a human mission to Mars, the return problem is even more difficult, with predicted velocities of up to 14 km/s, at approximately Mach 42 at the Earth-atmosphere entry. In addition to human return, it is very likely that future space-travel architecture will include returning cargo to the Earth, either for scientific purposes or for commercial reasons. Platinum, titanium, helium 3, and other metals, elements and minerals are all high-value commodities in limited supply on Earth, and it may be profitable to mine these substances throughout the Solar System and return them to Earth, if an economical method can be found. To date, several private corporations have been launched to pursue these goals. Because the heat shield is the last element to be used in an Earth-return mission, a high penalty is paid in the propellant mass required to carry the heat shield to the destination and back. If the heat shield could be manufactured in space, and then outfitted on the spacecraft prior to the reentry at Earth, then significant propellant and mass savings could be achieved during launch and space operations. Preliminary mission architecture scenarios are described, which explain the potential benefits that may be derived from using an in-situ fabricated regolith heat shield. In order to prove that this is a feasible technology concept, this project successfully fabricated heat shield materials from mineral simulant materials of lunar and Martian regolith by two methods: 1) Sintering and 2) Binding the simulant with a "room-temperature vulcanizing" (RTV) silicone formulated to withstand high temperatures. Initially a third type of fabrication was planned using the hot waste stream from regolith ISRU processes. This fabrication method was discarded since the resulting samples would be too dense and brittle for heat shields. High temperature flame tests at KSC and subsequent arc jet tests at Ames Research Center (ARC) have proved promising. These coupon tests show favorable materials properties and have the potential to be a new way of fabricating heat shields for space entry into planetary atmospheres.

Hogue, Michael D.↗

NASA NTRS2013

Out of the Autoclave Fabrication of LaRC[TradeMark] PETI-9 Polyimide Laminates

The NASA Langley Research Center developed polyimide system, LaRC PETI-9, has successfully been processed into composites by high temperature vacuum assisted resin transfer molding (HT-VARTM). To extend the application of this high use temperature material to other out-of-autoclave (OOA) processing techniques, the fabrication of PETI- 9 laminates was evaluated using only a vacuum bag and oven cure. A LaRC PETI-9 polyimide solution in NMP was prepared and successfully utilized to fabricate unidirectional IM7 carbon fiber prepreg that was subsequently processed into composites with a vacuum bag and oven cure OOA process. Composite panels of good quality were successfully fabricated and mechanically tested. Processing characteristics, composite panel quality and mechanical properties are presented in this work. The resultant properties are compared to previously developed LaRC material systems processed by both autoclave and OOA techniques including the well characterized, autoclave processed LaRC PETI-5.

Cano, Robert J.↗

NASA NTRS2013

Regolith Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication

This NIAC project investigated an innovative approach to provide heat shield protection to spacecraft after launch and prior to each EDL thus potentially realizing significant launch mass savings. Heat shields fabricated in situ can provide a thermal-protection system for spacecraft that routinely enter a planetary atmosphere. By fabricating the heat shield with space resources from materials available on moons and asteroids, it is possible to avoid launching the heat-shield mass from Earth. Regolith has extremely good insulating properties and the silicates it contains can be used in the fabrication and molding of thermal-protection materials. Such in situ developed heat shields have been suggested before by Lewis. Prior research efforts have shown that regolith properties can be compatible with very-high temperature resistance. Our project team is highly experienced in regolith processing and thermal protection systems (TPS). Routine access to space and return from any planetary surface requires dealing with heat loads experienced by the spacecraft during reentry. Our team addresses some of the key issues with the EDL of human-scale missions through a highly innovative investigation of heat shields that can be fabricated in space by using local resources on asteroids and moons. Most space missions are one-way trips, dedicated to placing an asset in space for economical or scientific gain. However, for human missions, a very-reliable heat-shield system is necessary to protect the crew from the intense heat experienced at very high entry velocities of approximately 11 km/s at approximately Mach 33 (Apollo). For a human mission to Mars, the return problem is even more difficult, with predicted velocities of up to 14 km/s, at approximately Mach 42 at the Earth-atmosphere entry. In addition to human return, it is very likely that future space-travel architecture will include returning cargo to the Earth, either for scientific purposes or for commercial reasons. Platinum, titanium, helium 3, and other metals, elements and minerals are all high-value commodities in limited supply on Earth, and it may be profitable to mine these substances throughout the Solar System and return them to Earth, if an economical method can be found. To date, several private corporations have been launched to pursue these goals. Because the heat shield is the last element to be used in an Earth-return mission, a high penalty is paid in the propellant mass required to carry the heat shield to the destination and back. If the heat shield could be manufactured in space, and then outfitted on the spacecraft prior to the reentry at Earth, then significant propellant and mass savings could be achieved during launch and space operations. Preliminary mission architecture scenarios are described, which explain the potential benefits that may be derived from using an in-situ fabricated regolith heat shield. In order to prove that this is a feasible technology concept, this project successfully fabricated heat shield materials from mineral simulant materials of lunar and Martian regolith by two methods: 1) Sintering and 2) Binding the simulant with a "room-temperature vulcanizing" (RTV) silicone formulated to withstand high temperatures. Initially a third type of fabrication was planned using the hot waste stream from regolith ISRU processes. This fabrication method was discarded since the resulting samples would be too dense and brittle for heat shields. High temperature flame tests at KSC and subsequent arc jet tests at Ames Research Center (ARC) have proved promising. These coupon tests show favorable materials properties and have the potential to be a new way of fabricating heat shields for space entry into planetary atmospheres.

Hogue, Michael D.↗

NASA NTRS2013

Fiber Reinforced Composite Cores and Panels

A fiber reinforced core panel is formed from strips of plastics foam helically wound with layers of rovings to form webs which may extend in a wave pattern or may intersect transverse webs. Hollow tubes may replace foam strips. Axial rovings cooperate with overlying helically wound rovings to form a beam or a column. Wound roving patterns may vary along strips for structural efficiency. Wound strips may alternate with spaced strips, and spacers between the strips enhance web buckling strength. Continuously wound rovings between spaced strips permit folding to form panels with reinforced edges. Continuously wound strips are helically wrapped to form annular structures, and composite panels may combine both thermoset and thermoplastic resins. Continuously wound strips or strip sections may be continuously fed either longitudinally or laterally into molding apparatus which may receive skin materials to form reinforced composite panels.

Day, Stephen W.↗

NASA NTRS2013

Low noise wing slat system with rigid cove-filled slat

Concepts and technologies described herein provide for a low noise aircraft wing slat system. According to one aspect of the disclosure provided herein, a cove-filled wing slat is used in conjunction with a moveable panel rotatably attached to the wing slat to provide a high lift system. The moveable panel rotates upward against the rear surface of the slat during deployment of the slat, and rotates downward to bridge a gap width between the stowed slat and the lower wing surface, completing the continuous outer mold line shape of the wing, when the cove-filled slat is retracted to the stowed position.

Shmilovich, Arvin↗

NASA NTRS2013

Three-Dimensional (3D) Additive Construction: Printing with Regolith

Three dimensional (3D) printing is a new and booming topic in many realms of research and engineering technology. When it comes to space science and aerospace engineering, it can be useful in numerous ways. As humans travel deeper into space and farther from Earth, sending large quantities of needed supplies from Earth for a mission becomes astronomically expensive and less plausible. In order to reach further to new places, In Situ Resource Utilization (ISRU), a project that pushes for technologies to use materials already present in the destination's environment, is necessary. By using materials already available in space such as regolith from the Moon, Mars, or an asteroid's surface, fewer materials need to be brought into space on a launched vehicle. This allows a vehicle to be filled with more necessary supplies for a deep space mission that may not be found in space, like food and fuel. This project's main objective was to develop a 3D printer that uses regolith to "print" large structures, such as a dome, to be used as a heat shield upon a vehicle's reentry into the atmosphere or even a habitat. 3D printing is a growing technology that uses many different methods to mix, heat, and mold a material into a specific shape. In order to heat the regolith enough to stick together into a solid shape, it must be sintered at each layer of material that is laid. Sintering is a process that heats and compresses a powdered material until it fuses into a solid, which requires a lot of energy input. As an alternative, a polymer can be mixed with the regolith before or as it is sent to the 3D printer head to be placed in the specific shape. The addition of the polymer, which melts and binds at much lower temperatures than sintering temperatures, greatly decreases the required heating temperature and energy input. The main task of the project was to identify a functional material for the printer. The first step was to find a miscible. polymer/solvent solution. This solution was added to the regolith and the solvent was evaporated essentially leaving polymer-coated regolith particles. This material would be sent through the printer head and heated layer by layer to melt the polymer and bind the regolith. This method was one of many in a large goal to utilize materials in space with a custom-made 3D printer that builds dome-shaped habitats and other essential equipment for future deep space missions.

Tsoras, Alexandra↗

NASA NTRS2013

Kennedy Space Center: Swamp Works

When I began my internship with the Granular Mechanics and Regolith Operations laboratory (GMRO), also known as Swamp Works, I was given the unique opportunity to shadow many teams working on various projects, and decide what projects I wanted to take part in. Before I go into details of my experiences at Swamp Works, I would like to take a moment to explain what I discovered Swamp Works to be. Swamp Works is a family of hardworking, dedicated, and driven people from various backgrounds and skill sets. These people all work to advance technologies and make science fiction science fact through means of rapid prototyping. They support and encourage failure as an option when learning new things, as long as lesson learned from said failure. In fact, their motto states "Fail, Fast, Forward." What this means is, not if but when one fails he or she must do so quickly and spring forward from the failure so that his or her progress is not delayed. With this acceptance, it provided me the confidence to dive into a multitude of projects working in various fields and with a wide range of skill sets. The first project I joined was Badger. My motivation for taking on this project was the opportunity I would have to obtain valuable experience working with 3D modeling and 3D printing technologies. Badger was a digging apparatus to be used in a highly dusty environment in a material known as Regolith. Regolith is a scientific term for the dirt or top soil found on planetary bodies. Regolith contains a large quantity of sediments less than lOppm and as a result poses a challenge of keeping it out of any cracks and crevices. Furthermore, regolith can create high levels of electrostatic energy, which can prove damaging to sensitive electrical hardware. With these characteristics in mind, I decided to take on the task of designing and manufacturing a dust proof cover for the sensitive electrical hardware. When I began this project, I did not have the slightest idea as to how to use 3D modeling software or a means of manufacturing a viable product. As I went along with variants of the design, I became very proficient with a 3D modeling program known as CREO 2.0. Upon completion of my 3D design, I then had the task of manufacturing and having, in my hands, a usable model. To do this I had to work with additive printing technologies also known as 3D printing. Through my experiences working with Badger, I realized that 3D modeling is the focal point in much of engineering. With this in mind, I have embraced this fact and decided to further my experience with this software so that I may become a more valuable asset to any firm later in my career. Mid-way through work with Badger, I picked up another project in which I found much interest. I ha~ the opportunity to work side by side with a materials and composites guru in manufacturing carbon composite coupons (test strips) for performing stress, strain, and sheer analysis on. Being from a surfing, kiteboarding, and other water sport background I have always been interested in board design. With this in mind, it is no wonder why I found interest in such a project. I had the opportunity to refine Mold preparatory, composite layup, and composite curing techniques. Following manufacturing of these composite strips, I then performed various stress tests and logged my results. With these results, future teams could create lighter, stronger, and more cost effective composite structures for use in varieties of applications. After my experiences with materials and composites testing, I have obtained crucial appreciation for detailed documentation and analysis that material sciences involve. However, as interesting as composite materials testing has been, I do not feel this is where my future career lies. Another, more on the side, project I have been involved in is building a 626 cubic foot regolith containment chamber for doing full scale testing of robotic systems. This chamber is built of high strength aluminum scaffold materials, 80/20, and massive panels of Lexan. Once the chamber is completed, it is be filled with 120 tons of regolith and dubbed the largest regolith test chamber in the world. Through my experiences with building "Big Bin" as we called it, I discovered my demand for engaging and hands on activities. Through all of my incredible experiences working with the Swamp Works at Kennedy Space Center; I have obtained crucial knowledge, insights, and experiences that have fuelled, shaped, and will continue to drive me toward my ultimate goal of obtaining not only a degree in Engineering, but obtaining a job that I can call a career. I want to give much thanks to all of those who mentored me along my journey, and to all who made this opportunity a reality.

DeFilippo, Anthony Robert↗

NASA NTRS2014

The Impact of Apollo-Era Microbiology on Human Space Flight

The microbiota of crewmembers and the spacecraft environment contributes significant risk to crew health during space flight missions. NASA reduces microbial risk with various mitigation methods that originated during the Apollo Program and continued to evolve through subsequent programs: Skylab, Shuttle, and International Space Station (ISS). A quarantine of the crew and lunar surface samples, within the Lunar Receiving Laboratory following return from the Moon, was used to prevent contamination with unknown extraterrestrial organisms. The quarantine durations for the crew and lunar samples were 21 days and 50 days, respectively. A series of infections among Apollo crewmembers resulted in a quarantine before launch to limit exposure to infectious organisms. This Health Stabilization Program isolated the crew for 21 days before flight and was effective in reducing crew illness. After the program developed water recovery hardware for Apollo spacecraft, the 1967 National Academy of Science Space Science Board recommended the monitoring of potable water. NASA implemented acceptability limits of 10 colony forming units (CFU) per mL and the absence of viable E. coli, anaerobes, yeasts, and molds in three separate 150 mL aliquots. Microbiological investigations of the crew and spacecraft environment were conducted during the Apollo program, including the Apollo-Soyuz Test Project and Skylab. Subsequent space programs implemented microbial screening of the crew for pathogens and acceptability limits on spacecraft surfaces and air. Microbiology risk mitigation methods have evolved since the Apollo program. NASA cancelled the quarantine of the crew after return from the lunar surface, reduced the duration of the Health Stabilization Program; and implemented acceptability limits for spacecraft surfaces and air. While microbial risks were not a main focus of the early Mercury and Gemini programs, the extended duration of Apollo flights resulted in the increased scrutiny of impact of the space flight environment on crew health. The lessons learned during that era of space flight continue to impact microbiology risk mitigation in space programs today.

Elliott, T. F↗

NASA NTRS2014

Aeroacoustics of Space Vehicles

While for airplanes the subject of aeroacoustics is associated with community noise, for space vehicles it is associated with vibro-acoustics and structural dynamics. Surface pressure fluctuations encountered during launch and travel through lower part of the atmosphere create intense vibro-acoustics environment for the payload, electronics, navigational equipment, and a large number of subsystems. All of these components have to be designed and tested for flight-certification. This presentation will cover all three major sources encountered in manned and unmanned space vehicles: launch acoustics, ascent acoustics and abort acoustics. Launch pads employ elaborate acoustic suppression systems to mitigate the ignition pressure waves and rocket plume generated noise during the early part of the liftoff. Recently we have used large microphone arrays to identify the noise sources during liftoff and found that the standard model by Eldred and Jones (NASA SP-8072) to be grossly inadequate. As the vehicle speeds up and reaches transonic speed in relatively denser part of the atmosphere, various shock waves and flow separation events create unsteady pressure fluctuations that can lead to high vibration environment, and occasional coupling with the structural modes, which may lead to buffet. Examples of wind tunnel tests and computational simulations to optimize the outer mold line to quantify and reduce the surface pressure fluctuations will be presented. Finally, a manned space vehicle needs to be designed for crew safety during malfunctioning of the primary rocket vehicle. This brings the subject of acoustic environment during abort. For NASAs Multi-Purpose Crew Vehicle (MPCV), abort will be performed by lighting rocket motors atop the crew module. The severe aeroacoustics environments during various abort scenarios were measured for the first time by using hot helium to simulate rocket plumes in the Ames unitary plan wind tunnels. Various considerations used for the helium simulation and the final confirmation from a flight test will be presented.

launch vehicle↗

NASA NTRS2014

Color Changing Material for Hydrogen Leak Detection

Kennedy Space Center scientists developed a hydrogen leak sensor utilizing a combination of chemochromic pigment and polymer that can be molded or fiber spun into rigid or flexible shapes such as tape. The sensor turns a dark color when exposed to hydrogen gas. This sensor has proven to be very effective for pinpointing the exact location of leaks in hydrogen gas lines and fittings at launch pads. Kennedy Space Center exclusively licensed this technology to the University of Central Florida (UCF), who also holds patents that are complimentary to KSC's. UCF has bundled the patents and exclusively licensed the portfolio to HySense Technology LLC, a startup company founded by a UCF professor who supports the UCF Florida Solar Energy Center (FSEC). HySense has fully developed its product (known as Intellipigment"TM"), and currently has five commercial customers. The company recently won the $100,000 first-place award at the CAT5 innovation competition at the Innovation Concourse of the Southeast: Safety & Manufacturing event in Orlando, FL. Commercial production and sales of this technology by HySense Technology will make this leak sensor widely available for use by NASA, DoD, and industries that utilize hydrogen gas.

Material for Hyrogen↗

NASA NTRS2014

AFC-Enabled Simplified High-Lift System Integration Study

The primary objective of this trade study report is to explore the potential of using Active Flow Control (AFC) for achieving lighter and mechanically simpler high-lift systems for transonic commercial transport aircraft. This assessment was conducted in four steps. First, based on the Common Research Model (CRM) outer mold line (OML) definition, two high-lift concepts were developed. One concept, representative of current production-type commercial transonic transports, features leading edge slats and slotted trailing edge flaps with Fowler motion. The other CRM-based design relies on drooped leading edges and simply hinged trailing edge flaps for high-lift generation. The relative high-lift performance of these two high-lift CRM variants is established using Computational Fluid Dynamics (CFD) solutions to the Reynolds-Averaged Navier-Stokes (RANS) equations for steady flow. These CFD assessments identify the high-lift performance that needs to be recovered through AFC to have the CRM variant with the lighter and mechanically simpler high-lift system match the performance of the conventional high-lift system. Conceptual design integration studies for the AFC-enhanced high-lift systems were conducted with a NASA Environmentally Responsible Aircraft (ERA) reference configuration, the so-called ERA-0003 concept. These design trades identify AFC performance targets that need to be met to produce economically feasible ERA-0003-like concepts with lighter and mechanically simpler high-lift designs that match the performance of conventional high-lift systems. Finally, technical challenges are identified associated with the application of AFC-enabled highlift systems to modern transonic commercial transports for future technology maturation efforts.

Hartwich, Peter M.↗

NASA NTRS2014

Effect of Preconditioning and Soldering on Failures of Chip Tantalum Capacitors

Soldering of molded case tantalum capacitors can result in damage to Ta205 dielectric and first turn-on failures due to thermo-mechanical stresses caused by CTE mismatch between materials used in the capacitors. It is also known that presence of moisture might cause damage to plastic cases due to the pop-corning effect. However, there are only scarce literature data on the effect of moisture content on the probability of post-soldering electrical failures. In this work, that is based on a case history, different groups of similar types of CWR tantalum capacitors from two lots were prepared for soldering by bake, moisture saturation, and longterm storage at room conditions. Results of the testing showed that both factors: initial quality of the lot, and preconditioning affect the probability of failures. Baking before soldering was shown to be effective to prevent failures even in lots susceptible to pop-corning damage. Mechanism of failures is discussed and recommendations for pre-soldering bake are suggested based on analysis of moisture characteristics of materials used in the capacitors' design.

multilayer ceramic capacitor (MLCC)↗

NASA NTRS2014

Design and Development of Aerogel-Based Antennas for Aerospace Applications: A Final Report to the NARI Seedling

As highly porous solids possessing low density and low dielectric permittivity combined with good mechanical properties, polyimide (PI) aerogels offer great promise as an enabling technology for lightweight aircraft antenna systems. While they have been aggressively explored for thermal insulation, barely any effort has been made to leverage these materials for antennas or other applications that take advantage of their aforementioned attributes. In Phase I of the NARI Seedling Project, we fabricated PI aerogels with properties tailored to enable new antenna concepts with performance characteristics (wide bandwidth and high gain) and material properties (low density, environmental stability, and robustness) superior to the state of practice (SOP). We characterized electromagnetic properties, including permittivity, reflectivity, and propagation losses for the aerogels. Simple, prototype planar printed circuit patch antennas from down-selected aerogel formulations were fabricated by molding the aerogels to net shapes and by gold-metalizing the pattern onto the templates via electron beam evaporation in a clean room environment. These aerogel based antennas were benchmarked against current antenna SOP, and exhibited both broader bandwidth and comparable or higher gain performance at appreciably lower mass. Phase II focused on the success of the Phase I results pushing the PI aerogel based antenna technology further by exploring alternative antenna design (i.e., slot coupled antennas) and by examining other techniques for fabricating the antennas including ink jet printing with the goal of optimizing antenna performance and simplifying production. We also examined new aerogel formulations with better moisture and solvent resistance to survive processing conditions. In addition, we investigated more complex antenna designs including passive phased arrays such as 2x4 and 4x8 element arrays to assess the scalability of the aerogel antenna concept. Furthermore, we explored the possibility of developing these arrays in thin, flexible form to make conformable antennas.

insulation↗

NASA NTRS2014

Additive Manufacturing: Ensuring Quality for Spacecraft Applications

Reliable manufacturing requires that material properties and fabrication processes be well defined in order to insure that the manufactured parts meet specified requirements. While this issue is now relatively straightforward for traditional processes such as subtractive manufacturing and injection molding, this capability is still evolving for AM products. Hence, one of the principal challenges within AM is in qualifying and verifying source material properties and process control. This issue is particularly critical for applications in harsh environments and demanding applications, such as spacecraft.

Additive Manufacturing↗