Abstract
In March and April 2024, a multispectral imaging drone was modified for multispectral polarimetric imaging (MPI) to explore its capabilities. The study targeted rooftop photovoltaic (PV) panels, examin ing environmental variables affecting their surfaces, and isolated trees, analyzing spectropolarimetric effects of multiple scattering in leaves before and after canopy development. Bandpass filters targeted chlorophyll absorption (~650-680 nm), red edge transition (~680-750 nm), and near-infrared reflectance plateau (~750-850 nm). One flight tested drone characteristics, while two acquired MPI data. The drone, equipped with a polarizer,was calibrated in the laboratory to normalize flight data.
Percent linear polarization (PLP) and angle of polarization (AOP) were derived for PV panels, interpret ed using manufacturer specifications, and for trees with and without canopy, analyzed with standardized methods. Cloudiness during the "tree with canopy" flight introduced diffuse illumination, affecting scat tering patterns, which were similar between datasets. This suggests diffuse light dominated polarization signals, necessitating further measurements.
The primary goals-modifying the drone for MPI and defining its quantitative imaging capabilities-were achieved. The platform successfully captured spectral and polarization data, advancing remote sensing for PV panel monitoring and vegetation analysis. Limitations included only two data flights and cloudi ness impacting polarization measurements. Future work will address these by optimizing flight conditions and expanding datasets. This study highlights MPI's potential for material and ecological applications, emphasizing the need for robust calibration and environmental correction to ensure reliable polarimetric data.
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