Engineering topics

Chelsea Pickett

Publications and source records attributed to Chelsea Pickett.

5 records

NASA NTRS2023

Moon-to-Mars Planetary Autonomous Construction Technology: MMPACT Material Screening

NASA’s Space Technology Mission Directorate “champions technologies needed to live on and explore the Moon” [1]. This includes capabilities that capitalize on existing lunar resources and carry out surface manufacturing and construction activities. The goal of the Moon-to-Mars Planetary Construction Technology (MMPACT) Project is to mature these two capabilities. The primary resource on the Moon and the primary feedstock for manufacturing and construction is regolith. In the past, astronauts launched, landed, and lived in a spacecraft. NASA envisions a future where we make living spaces on the lunar surface instead. The innovative technologies required for lunar surface construction may be something never seen before, or they may be adaptations of existing technologies. MMPACT must screen for the most feasible technologies with the earliest potential technology insertions given the ambitious goals of the Artemis campaign. This poster summarizes recent efforts to discover and document mechanical and thermal capabilities of various technologies: a laser-based vitreous material transformation from Texas-based ICON, a molten extrusion process from ICON, a mortar from MSFC, a mortar from an MSFC-Louisiana State University partnership, and a geopolymer from a MSFC-Pennsylvania State University partnership. Other testing and development activities are documented as well. [1] https://www.nasa.gov/directorates/spacetech/Lunar_Surface_Innovation_Initiative

In-situ Resource Utilization↗

NASA NTRSDate not supplied

Composite Technologies for Science Missions

ASTROLAB, Lunar Geophysical Network, Mars Icebreaker and Mars PLACER Net missions propose use of various types of vehicles – such as rovers, landers and flying probes - to accomplish their scientific objectives. Although designs for such vehicles are myriad, many structural components can be made using composite manufacturing technologies. Composite materials are also myriad, by nature, but carbon fiber reinforced polymers (CFRP) in particular are sought after for their high specific strength and specific stiffness. CFRP components could be especially beneficial in vehicle designs for Moon or Mars missions due to their nearly negligible coefficient of thermal expansion (CTE). CTE is a critical design characteristics in environments where significant thermal swings are prevalent, such as those of atmosphere-less Moon and Mars.MSFC/EM42 houses several relevant composites technologies. Strong and rigid struts can be filament-wound. Shells and platforms can be laid-up using automated fiber placement (for repeatability) or by hand (for small features). Monolithic structures can even be designed to reduce part count and therefore reduce the risk of joint failures. Composites are also tailorable, allowing the incorporation of different material types or formats through the thickness of a part. This includes materials which shield from radiation or electrostatic discharge. Finally, the rigidity of composite parts minimizes overall vibration and compliance within a design.Additionally, missions such as Triton Ocean World Surveyor anticipate use of traditional, metallic fuel tanks. Composite overwrapped pressure vessels (COPVs) are suitable for use in this application as well. The Triton mission even cites a concern for heat retention, for which CFRP also offers improved characteristics over traditional metallic tanks.

Lightweight↗

NASA NTRSDate not supplied

Process Development and Testing for Lunar Habitats

Non-metallic solutions for Lunar bases are appealing due to their light weight and ability to block many forms of radiation. Composite materials made from different combinations of these non-metallic materials enable effective mating of dissimilar materials for strong structures such as pressurized habitats. Inserting and manufacturing composite structural materials on the Moon presents several challenges, however: the oxygen levels inside pressurized habitats will be relatively high, radiation that is blocked causes damage and the lack of atmosphere results in a high-magnitude negative pressure environment. In the past two years, the Materials and Processes Lab (EM01) invested in two internal research and development (IRAD) proposals for testing and procurement of composite materials. One proposal endeavors to determine flammability and radiation damage of various composite materials with a focus on carbon fiber and ultra-high molecular weight polyethylene (UHWMPE). The other proposal enables procurement of chopped fiber spray equipment materials which will be used to develop a novel technique for chopped UHMWPE fiber layup, similar to the chopped fiberglass layups used for making large structures such a boat hulls and hot tubs.

Composite↗

NASA NTRSDate not supplied

Composite Materials for Space Habitats

Composite materials are an appealing choice for space habitats to reduce weight while maintaining strength and dimensional stability that is required in these sorts of structures. These materials can provide some shielding from the radiation that is present in the natural space environment; however, they can become damaged in the process. Damage is measured here using open-hole tension testing. This study quantifies the mechanical impact of a 10-year Lunar surface mission on a selection of composite materials.

Structures↗

NASA NTRSDate not supplied

Process Development and Testing for Lunar Habitats

Non-metallic composites are appealing for Lunar habitats due to their low specific weight and contribution to passive radiation shielding. This application of composite materials presents notable challenges, however: flammability risks are higher due to elevated oxygen levels expected in habitat structures and absorbed radiation can cause damage long-term. The Materials and Processes Laboratory at Marshall Space Flight Center awarded funding for an internal research and development study which included fabrication and testing of composite materials for Lunar habitats. Composite layups used carbon fiber or ultra-high molecular weight polyethylene reinforcement and a variety of polymer matrices. Pre-impregnated fabric was autoclave cured; however, novel coatings were incorporated during select layups. Samples from each panel were used for screening-level flammability testing (ASTM D 2863) and combined vacuum ultraviolet and electron irradiation followed by tension testing (ASTM D5766). Two of the tested composite materials exceeded a 37% limiting oxygen index. Material property degradation for a 10 year simulated radiation dose was minimal in most cases.

manufacturing↗