Search NASA⌕ Search

Engineering topics

S. R. Deitrick

Publications and source records attributed to S. R. Deitrick.

Dust Solution Testing Initiative (DuSTI): Infusing Commercial Off the Shelf Dust Mitigation Technologies with NASA Practices

Dust is one of the most significant hazards to human lunar exploration. However, since the Apollo program concluded, limited research has been performed on lunar dust mitigation technologies. The safety of the crew members and sustainability of habitats, science, and supporting hardware depend on effective dust mitigation techniques and technologies. As NASA pursues a new generation of lunar missions with the Artemis program, the project team will pursue dust mitigation solutions with the Dust Solution Testing Initiative (DuSTI). DuSTI is a lunar dust mitigation effort that involves performing tests on commercial off the shelf (COTS) technologies over FY21. DuSTI will preform component and subsystem tests in dusty environments for up to five technologies with high potential. The specific technologies identified for study were selected based on several factors, including a market analysis of current terrestrial dust mitigation applications, availability of the technology, accessibility of various testing facilities, and cost of procurement. These technologies support the active and passive dust mitigation requirements of filtration systems, electro-mechanical systems, electro-static systems, surface coatings, textiles, and silicone polymers. Technology Readiness Level (TRL) will be increased by validating components in relevant environments. For example, if the COTS technology is at a TRL 9 for terrestrial use but at a 4-5 TRL for use in the lunar environment, we will test that technology in a lunar dust environment to increase the TRL for use on the Moon.

lunar dust↗

Regolith Simulant Report Cards: A User Friendly Simulant Certification System

As the nation prepares to return to the Moon, there is an increasing need for testing tools, instruments, and equipment in simulated lunar regolith to ensure successful operations during lunar missions. Because of this, it is important to use accurate lunar regolith simulants to prepare for these missions. To address this, we are building an objective certification and reporting system for regolith simulants to ensure suitable simulants are being used for the appropriate use cases. Previous systems like the Figures of Merit (FoM) [1] and the Lunar Regolith Simulant User’s Guide fit-to-use matrices [2] for lunar simulants were not particularly user friendly. Some of the Figures of Merit were not clearly defined and did not include recommended baseline values of lunar regolith properties to compare simulants to, and the fit-to-use matrices are out of date and include simulants that are no longer in production and do not include simulants that have been developed since.

S. R. Deitrick↗

Grain Shape Characterization as an Enabling Capability for Lunar Surface Technologies

Lunar regolith has unique physical and geotechnical properties compared with familiar granular materials on Earth, and most lunar simulants as well. Specifically, the cohesion, angle of repose, and compressibility are much higher, and flowability is much lower for lunar regolith than otherwise similar terrestrial-derived materials[1,2]. There is confusion in the literature about the relative importance of vacuum, gravity, and inherent grain characteristics in driving these differences. Here we emphasize the importance of characterizing grain types and shapes for designing and test-ing lunar surface technologies, including for rover mobility, material handling, soil sampling, and heat transfer analyses. We demonstrate laboratory capabilities and preliminary studies, and outline further work to better characterize and simulate lunar grains to reduce risks for surface activities

K. M. Cannon↗