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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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71 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Mars habitat

The objective of this study is to develop a conceptual design for a permanently manned, self-sustaining Martian facility, to accommodate a crew of 20 people. The goal is to incorporate the major functions required for long term habitation in the isolation of a barren planet into a thriving ecosystem. These functions include living, working, service, and medical facilities as well as a green house. The main design task was to focus on the internal layout while investigating the appropriate structure, materials, and construction techniques. The general concept was to create a comfortable, safe living environment for the crew members for a stay of six to twelve months on Mars. Two different concepts were investigated, a modular assembly reusable structure (MARS) designated Lavapolis, and a prefabricated space frame structure called Hexamars. Both models take into account factors such as future expansion, radiation shielding, and ease of assembly.

Ayers, Dale↗
NASA NTRS1991

Indigenous lunar construction materials

The utilization of local resources for the construction and operation of a lunar base can significantly reduce the cost of transporting materials and supplies from Earth. The feasibility of processing lunar regolith to form construction materials and structural components is investigated. A preliminary review of potential processing methods such as sintering, hot-pressing, liquification, and cast basalt techniques, was completed. The processing method proposed is a variation on the cast basalt technique. It involves liquification of the regolith at 1200-1300 C, casting the liquid into a form, and controlled cooling. While the process temperature is higher than that for sintering or hot-pressing (1000-1100 C), this method is expected to yield a true engineering material with low variability in properties, high strength, and the potential to form large structural components. A scenario for this processing method was integrated with a design for a representative lunar base structure and potential construction techniques. The lunar shelter design is for a modular, segmented, pressurized, hemispherical dome which could serve as habitation and laboratory space. Based on this design, estimates of requirements for power, processing equipment, and construction equipment were made. This proposed combination of material processing method, structural design, and support requirements will help to establish the feasibility of lunar base construction using indigenous materials. Future work will refine the steps of the processing method. Specific areas where more information is needed are: furnace characteristics in vacuum; heat transfer during liquification; viscosity, pouring and forming behavior of molten regolith; design of high temperature forms; heat transfer during cooling; recrystallization of basalt; and refinement of estimates of elastic moduli, compressive and tensile strength, thermal expansion coefficient, thermal conductivity, and heat capacity. The preliminary design of the lunar shelter showed us that joining is a critical technology needed for building a structure from large segments. The problem of joining is important to the design of any structure that is not completely prefabricated. It is especially important when the structure is subjected to tensile loading by an internal pressure. For a lunar shelter constructed from large segments the joints between these large segments must be strong, and they must permit automated construction. With a cast basalt building material which is brittle, there is the additional problem of connecting the joint with the material and avoiding stress concentration that would cause failure. Thus, a well-defined project which we intend to pursue during this coming year is the design of joints for cast basalt structural elements.

Rogers, Wayne P.↗
NASA NTRS1992

Design of highly damage-tolerant sandwich panels

The effects of different fabrication procedures to increase the damage tolerance of sandwich panels were studied. Baseline panels consisted of a 25.4 mm premolded core, surfaced with 177 C cure film adhesive and carbon-bismaleimide prepreg which were subsequently cocured onto the core. It was found that panels with a prefabricated skin, which was subsequently bonded onto the core with room temperature cure adhesive, showed greatly increased damage tolerance.

Hiel, Clement↗
NASA NTRS1992

Design and development of the second generation Mars Habitat

The second generation of Mars Habitat is to be utilized as an advanced permanent base for 20 crew members to live on Mars for a period of 6-12 months. It is designed to be a self-contained environment accommodating five main facilities: living, working, service, medical, and a greenhouse. The objective of the design is to create a comfortable, safe, living environment. Hexamars-2 and Lavapolis-2 are two different concepts for the advanced Mars Habitat. The design team assumes there will be an initial habitat located near or on the site from earlier missions that satisfies the requirement for a short-term habitation for the crew to use while constructing Hexamars-2 or Lavapolis-2. Prefabricated structures and materials will be shipped to the site before the long-term crew members arrive. Partial construction and preparation for the long-term habitat will be done by crew members or robotics from a previous mission. The construction of the long-term base will occur in phases. Hexamars-2 consists of six sphere-shaped inflatable modules that will be partially buried below the Martian surface. The construction of each sphere will occur in ten steps. Shape charges will be used to create the crater in which the spherical structure will be placed. The interior core will be unloaded and put into place followed by the exterior structure. The foundation will be filled, the interior bladder will be inflated, floor-to-floor joists connected, and sand pockets filled. Finally, the life support system and interior partitions are put in place. Each sphere consists of three levels of which the lower level will be safe haven. Particular attention is given to structural support, the dominance of internal pressure, the process of construction, and human factors.

Sabouni, Ikhlas↗
NASA NTRS1996

Design and evaluation of a bolted joint for a discrete carbon-epoxy rod-reinforced hat section

The use of prefabricated pultruded carbon-epoxy rods has reduced the manufacturing complexity and costs of stiffened composite panels while increasing the damage tolerance of the panels. However, repairability of these highly efficient discrete stiffeners has been a concern. Design, analysis, and test results are presented in this paper for a bolted-joint repair for the pultruded rod concept that is capable of efficiently transferring axial loads in a hat-section stiffener on the upper skin segment of a heavily loaded aircraft wing component. A tension and a compression joint design were evaluated. The tension joint design achieved approximately 1.0% strain in the carbon-epoxy rod-reinforced hat-section and failed in a metal fitting at 166% of the design ultimate load. The compression joint design failed in the carbon-epoxy rod-reinforced hat-section test specimen area at approximately 0.7% strain and at 110% of the design ultimate load. This strain level of 0.7% in compression is similar to the failure strain observed in previously reported carbon-epoxy rod-reinforced hat-section column tests.

Rousseau, Carl Q.↗
NASA NTRS1999

High-Energy Space Propulsion Based on Magnetized Target Fusion

A conceptual study is made to explore the feasibility of applying magnetized target fusion (MTF) to space propulsion for omniplanetary travel. Plasma-jet driven MTF not only is highly amenable to space propulsion, but also has a number of very attractive features for this application: 1) The pulsed fusion scheme provides in situ a very dense hydrogenous liner capable of moderating the neutrons, converting more than 97% of the neutron energy into charged particle energy of the fusion plasma available for propulsion. 2) The fusion yield per pulse can be maintained at an attractively low level (< 1 GJ) despite a respectable gain in excess of 70. A compact, low-weight engine is the result. An engine with a jet power of 25 GW, a thrust of 66 kN, and a specific impulse of 77,000 s, can be achieved with an overall engine mass of about 41 metric tons, with a specific power density of 605 kW/kg, and a specific thrust density of 1.6 N/kg. The engine is rep-rated at 40 Hz to provide this power and thrust level. At a practical rep-rate limit of 200 Hz, the engine can deliver 128 GW jet power and 340 kN of thrust, at specific power and thrust density of 1,141 kW/kg and 3 N/kg respectively. 3) It is possible to operate the magnetic nozzle as a magnetic flux compression generator in this scheme, while attaining a high nozzle efficiency of 80% in converting the spherically radial momentum of the fusion plasma to an axial impulse. 4) A small fraction of the electrical energy generated from the flux compression is used directly to recharge the capacitor bank and other energy storage equipment, without the use of a highvoltage DC power supply. A separate electrical generator is not necessary. 5) Due to the simplicity of the electrical circuit and the components, involving mainly inductors, capacitors, and plasma guns, which are connected directly to each other without any intermediate equipment, a high rep-rate (with a maximum of 200 Hz) appears practicable. 6) All fusion related components are within the current state of the art for pulsed power technology. Experimental facilities with the required pulsed power capabilities already exist. 7) The scheme does not require prefabricated fuel target and liner hardware in any esoteric form or state. All necessary fuel and liner material are introduced into the engine in the form of ordinary matter in gaseous state at room temperature, greatly simplifying their handling on board. They are delivered into the fusion reaction chamber in a completely standoff manner.

Thio, Y. C. F.↗
NASA NTRS2007

Analyzing Responses of Chemical Sensor Arrays

NASA is developing a third-generation electronic nose (ENose) capable of continuous monitoring of the International Space Station s cabin atmosphere for specific, harmful airborne contaminants. Previous generations of the ENose have been described in prior NASA Tech Briefs issues. Sensor selection is critical in both (prefabrication) sensor material selection and (post-fabrication) data analysis of the ENose, which detects several analytes that are difficult to detect, or that are at very low concentration ranges. Existing sensor selection approaches usually include limited statistical measures, where selectivity is more important but reliability and sensitivity are not of concern. When reliability and sensitivity can be major limiting factors in detecting target compounds reliably, the existing approach is not able to provide meaningful selection that will actually improve data analysis results. The approach and software reported here consider more statistical measures (factors) than existing approaches for a similar purpose. The result is a more balanced and robust sensor selection from a less than ideal sensor array. The software offers quick, flexible, optimal sensor selection and weighting for a variety of purposes without a time-consuming, iterative search by performing sensor calibrations to a known linear or nonlinear model, evaluating the individual sensor s statistics, scoring the individual sensor s overall performance, finding the best sensor array size to maximize class separation, finding optimal weights for the remaining sensor array, estimating limits of detection for the target compounds, evaluating fingerprint distance between group pairs, and finding the best event-detecting sensors.

Zhou, Hanying↗
NASA NTRS2011

Fiber Optic Thermal Detection of Composite Delaminations

A recently developed technique is presented for thermographic detection of delaminations in composites by performing temperature measurements with fiber optic Bragg gratings. A single optical fiber with multiple Bragg gratings employed as surface temperature sensors was bonded to the surface of a composite with subsurface defects. The investigated structure was a 10-ply composite specimen with prefabricated delaminations of various sizes and depths. Both during and following the application of a thermal heat flux to the surface, the individual Bragg grating sensors measured the temporal and spatial temperature variations. The data obtained from grating sensors were analyzed with thermal modeling techniques of conventional thermography to reveal particular characteristics of the interested areas. Results were compared and found to be consistent with the calculations using numerical simulation techniques. Also discussed are methods including various heating sources and patterns, and their limitations for performing in-situ structural health monitoring.

Wu, Meng-Chou↗
NASA NTRS2005

Advanced Metal Foam Structures for Outer Space

A document discusses a proposal to use advanced materials especially bulk metallic glass (BMG) foams in structural components of spacecraft, lunar habitats, and the like. BMG foams, which are already used on Earth in some consumer products, are superior to conventional metal foams: BMG foams have exceptionally low mass densities and high strength-to-weight ratios and are more readily processable into strong, lightweight objects of various sizes and shapes. These and other attractive properties of BMG foams would be exploited, according to the proposal, to enable in situ processing of BMG foams for erecting and repairing panels, shells, containers, and other objects. The in situ processing could include (1) generation of BMG foams inside prefabricated deployable skins that would define the sizes and shapes of the objects thus formed and (2) thermoplastic deformation of BMG foams. Typically, the generation of BMG foams would involve mixtures of precursor chemicals that would be subjected to suitable pressure and temperature schedules. In addition to serving as structural components, objects containing or consisting of BMG foams could perform such functions as thermal management, shielding against radiation, and shielding against hypervelocity impacts of micrometeors and small debris particles.

Hanan, Jay↗
NASA NTRS2004

Fabrication of Robust, Flat, Thinned, UV-Imaging CCDs

An improved process that includes a high-temperature bonding subprocess has been developed to enable the fabrication of robust, flat, silicon-based charge-coupled devices (CCDs) for imaging in ultraviolet (UV) light and/or for detecting low-energy charged particles. The CCDs in question are devices on which CCD circuitry has already been formed and have been thinned for backsurface illumination. These CCDs may be delta doped, and aspects of this type of CCD have been described in several prior articles in NASA Tech Briefs. Unlike prior low-temperature bonding subprocesses based on the use of epoxies or waxes, the high-temperature bonding subprocess is compatible with the deltadoping process as well as with other CCD-fabrication processes. The present improved process and its bonding, thinning, and delta-doping subprocesses, are characterized as postfabrication processes because they are undertaken after the fabrication of CCD circuitry on the front side of a full-thickness silicon substrate. In a typical case, it is necessary to reduce the thickness of the CCD to between 10 and 20 m in order to take advantage of back-side illumination and in order to perform delta doping and/or other back-side treatment to enhance the quantum efficiency. In the prior approach to the fabrication of back-side-illuminated CCDs, the thinning subprocess turned each CCD into a free-standing membrane that was fragile and tended to become wrinkled. In the present improved process, prior to thinning and delta doping, a CCD is bonded on its front side to a silicon substrate that has been prefabricated to include cutouts to accommodate subsequent electrical connections to bonding pads on the CCD circuitry. The substrate provides structural support to increase ruggedness and maintain flatness. At the beginning of this process, the back side of a CCD as fabricated on a full-thickness substrate is polished. Silicon nitride is deposited on the back side, opposite the bonding pads on the front side, in order to define a relatively thick frame. The portion of the CCD not covered by the frame is the portion to be thinned by etching.

Grunthaner, Paula↗
NASA NTRS2013

Faxing Structures to the Moon: Freeform Additive Construction System (FACS)

Using the highly articulated All-Terrain Hex-Limbed Extra-Terrestrial Explorer (ATHLETE) robotic mobility system as a precision positioning tool, a variety of print head technologies can be used to 3D print large-scale in-situ structures on planetary surfaces such as the moon or Mars. In effect, in the same way CAD models can be printed in a 3D printer, large-scale structures such as walls, vaults, domes, berms, paving, trench walls, and other insitu derived elements can be FAXed to the planetary surface and built in advance of the arrival of crews, supplementing equipment and materials brought from earth. This paper discusses the ATHLETE system as a mobility / positioning platform, and presents several options for large-scale additive print head technologies, including tunable microwave "sinterator" approaches and in-situ concrete deposition. The paper also discusses potential applications, such as sintered-in-place habitat shells, radiation shielding, road paving, modular bricks, and prefabricated construction components.

Apollo Lunar Module↗
NASA NTRS2024

Establishing Standards for Lunar In Situ Resource Utilization Structural Materials

Lunar structures will be exposed to one of the most extreme environments that have ever been considered for human settlements. In situ, regolith-based materials are being proposed for construction on the moon, offering the benefit of reducing the cost of transporting large amounts of materials or prefabricated elements, and relying on the ability to transport mainly the equipment needed to construct landing pads, shelters, blast shields, habitats, roadways, etc. However, the properties of materials that are made, all or in part, from indigenous lunar resources are likely to change based on the make-up of the material, the location where it was taken from, the production processes, and time. No standards or building codes exist for the design and construction of infrastructure on the moon. Engineers will need dependable information about these materials before any design can be completed. Hard-won lessons from centuries of using similar resources on Earth need to be leveraged to develop the best procedures that will be critical for testing such materials for structural applications. Here we discuss the technical challenges of establishing such standards. Using the timely example of a landing pad on the moon, we identify the gaps in both knowledge and testing capabilities that exist today.

Shirley J. Dyke↗
NASA NTRS2026

Extrusion-based Additive Manufacturing of Regolith-Filled Shape Memory Vitrimer Composite for Lunar Construction

The National Aeronautics and Space Administration (NASA) is visiting the moon again. This time, the objective is to explore establishing a permanent lunar base. To achieve both longterm human habitation on the moon and future deep space travel, it is crucial to make the most of the in-situ resources and build autonomous systems on the moon to support the construction of a lunar habitat. NASA’s In-situ Resource Utilization (ISRU) program aims to minimize the need to ship heavy prefabricated structures, reducing cost and enhancing sustainability. Here, we developed an economical extrusion method for printing lunar regolith-based composites using shape memory vitrimer as a binder. A rheological study is conducted to determine the extrudability of the composite with different regolith weight percentages. Several characterizations were conducted on the composites. The as-printed composites exhibited compressive and flexural strengths of 73.32 MPa and 156.59 MPa, respectively, and good impact tolerance. The composite maintained 57.92% of its mechanical properties even after the second crack healing cycle. The composites also exhibit shape fixity ratio of 90.02% and shape recovery ratio of 83.46%. The simple synthesis method, sustainability, and good thermomechanical properties make the 3D printed composite an ideal material for lunar construction applications.

Kingsley Yeboah Gyabaah↗
DOE OSTI2026

Affordable and Scalable Modular Multifamily Housing: A Case Study on Cost, Construction Time Savings, and Waste Reduction in California: Preprint

Modular construction can significantly reduce waste when compared to traditional methods. This case study evaluates cost, construction time, and waste metrics for a 195-unit stick-built project and for a 66-unit modular project both based in Los Angeles, CA. We partner with SoLa Impact (real estate developer) and Model/Z (modular manufacturer) to evaluate the impact of Model/Z's 1-bedroom modular unit which is produced in a 160,000 sq ft local factory in South Los Angeles. We compare them to similar stick-built/site-built multifamily construction by the same developer in Los Angeles. This study finds that modular production reduced construction waste through precise prefabrication, concentrated workforce expertise, and streamlined logistics while cutting transportation needs, improving project efficiency and lowering associated timelines and costs. Economies of scale are being realized as Model/Z has produced over 500 affordable housing units and supplied for projects up to 188 units, shortening schedules and lowering per-unit costs and supporting affordable housing goals in income-challenged South Los Angeles. Modular methods offer a scalable, resource-efficient pathway to increasing affordable housing supply while reducing total development costs by 10-15% and project timelines by 50%, while simultaneously creating local jobs and training opportunities.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Transformative Efficiency and Automation in Modular Homes (TEAMH)

This report documents the Transformative Efficiency and Automation in Modular Homes (TEAMH) project, which evaluates the integration of advanced building envelope technologies and automation-assisted modular construction to improve residential energy performance and construction efficiency. The study investigates high-performance insulation systems, including vacuum insulation panels (VIPs), combined with light gauge steel (LGS) modular construction and factory automation. Laboratory testing, whole-building energy modeling across multiple climate zones, and factory demonstrations were conducted to assess thermal performance, energy savings, and production efficiency. Results indicate that upgraded envelope assemblies can achieve up to ~50% heating and ~34% cooling energy savings relative to IECC 2018 code-compliant homes, while automation-assisted construction can reduce wall assembly time by 24%–46% compared to conventional wood framing. The findings demonstrate the potential for scalable, high-performance modular homes that deliver significant energy savings with competitive projected costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

A Recipe for ABC Multifamily Retrofits: Technologies, Financing, and Project Delivery

This report documents the final technical accomplishments and outcomes of Rocky Mountain Institute’s project under the U.S. Department of Energy (DOE) Award DE-EE0009064. The project aimed to develop, validate, and scale whole building retrofit solutions for multifamily buildings, including two configurations of Integrated Mechanical System Pods (IMSP-C and IMSP-U), in alignment with DOE Advanced Building Construction (ABC) initiative's decarbonization and energy efficiency goals. While the project made significant progress in Budget Period 1 (Phase 1) and throughout Budget Period 2 (Phase 2), activities were discontinued as of March 26, 2025, following a Stop Work Order issued by DOE. As such, this report reflects all completed work through that date. The project did not enter Budget Periods 3 and 4 (Phase 2), and demonstration site implementation, field M&V, and final commercialization execution were not conducted.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2026

A Simple Panel System to Overcome Interface Challenges for Retrofits: Preprint

Retrofitting buildings is usually an expensive and labor-intensive process. Weatherization measures can improve comfort and energy affordability to some extent, but deep energy retrofits are needed to optimize performance and comfort, and to achieve significant energy cost savings. Barriers to deep energy retrofits include a limited supply of skilled labor, different building types, planning complexity, split incentives, and a long or non-existent ROI horizon. The "Simple Panel System" (SPS) workflow developed and demonstrated in this effort streamlines deep energy retrofits by applying advanced site capture, machine learning, and mixed reality to panelized construction. The result is a one-stop, product-independent solution for rapidly scalable retrofits with the potential to reduce construction time and project costs by 50%. Soft costs are reduced by more than 66%, total costs by more than 50%, and field construction time by more than 50% - not to mention the reduction in construction waste, improvement in working conditions, and the ability to scale without an influx of skilled labor. This paper presents the SPS and the preliminary results and findings from the pilot project.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗