COMPARISONS OF A CONSTRAINED LEAST SQUARES MODEL VERSUS HUMAN-IN-THE-LOOP FOR SPECTRAL UNMIXING TO DETERMINE MATERIAL TYPE OF GEO DEBRIS

摘要

Visible Spectral reflectance data was collected at LasrnCampanas Observatory * using an imagingrnspectrograph. Five pieces of Geosynchronous Orbitrn(GEO) were identified and observed. In addition,rnlaboratory spectral reflectance data was collected onrnseveral typical common spacecraft materials.rnThe remotely collected data and the laboratoryacquiredrndata were incorporated in a model that usesrna constrained linear least squares method (CLLS) tornunmix the spectrum in specific material components.rnThe results of this model are compared to thernprevious method of a human-in-the-loop (traditionalrnmethod (TM)), which identifies possible materialrncomponents by visual inspection. The CLLS methodrnwas in general more accurate at determining thernmaterials, while the TM was able to determine thernpercentages of the materials in the spectrum.