Characterization of Lunar Simulant Deposition on Seals for Lunar Surface Applications

Since its development at NASA Glenn Research Center (GRC) in 2020, the Uniform Dust Deposition System (UDDS) has been used to evenly deposit precise amounts of lunar regolith simulant onto a wide range of materials and test articles. Equally important to the uniformity of and control over the simulant deposition is the ability to accurately quantify the amount of simulant deposited. This paper outlines the method that has been developed to make these deposition level measurements and relevant considerations when adapting this method for other similar applications. An overview of the equipment used is provided, highlighting key specifications. The benefits and drawbacks of a range of potential image processing techniques are described, justifying panoptic segmentation as the most insightful approach for characterizing dust deposited on a surface. The importance of applying basic sampling statistics is emphasized to allow the generation of confidence intervals about various measures of dust deposition level. All prior considerations are integrated in an overview of the current image processing methodology used with the UDDS to characterize lunar simulant deposited on the surface of elastomer seals, as an example. Lastly, a few emerging areas of interest are described and contextualized: correlating image-based measures of deposition level with mass-based approaches and using image data to generate alternative predictors of performance that incorporate underlying physics specific to the test article.