[S-RD24] Cutting-edge sensing technology applied to geology and resource exploration

[SRD24-P05] Development of various ground measurement methods for multi-wavelength remote sensing by microsatellites and drones

*Nobuyasu Naruse¹, Yukihiro Takahashi² (1.School of Medicine, Shiga University of Medical Science, 2.Graduate School of Science, Hokkaido University)

Keywords:spectrometer, spectral library, microsatellite, drone

Based on the recognition that spectral data measured on the ground are the most important for interpreting images from small drones and microsatellites equipped with multi-wavelength multiband cameras and hypersensors, we have developed a compact spectrograph to efficiently create a spectral information database (spectral library) on the ground. Furthermore, this spectrograph was mounted on a 5-9 m pole and measured at 360° azimuth and 90° elevation angles at 5-10° intervals, respectively, to capture spectral images in the visible light range within a radius of about 40 m to achieve actual spectral mapping. Based on these images, it is possible to confirm the accuracy of geological and resource indexing in advance before flying a drone or satellite, to create an index using the data, and to confirm differences in spectra depending on the angle and azimuth at which the images are taken.
In addition, if all colors are photographed in the same way as above, the amount of data and cost will be high, and the advantages of multi-wavelength spectral imaging cannot be utilized after all. Therefore, we extracted from a spectral library a combination of four colors that can efficiently discriminate the target object and developed a camera equipped with filters for these four bands. By installing this camera on a drone, the cost of multi-wavelength imaging can be reduced to 1/20, and a world in which drone imaging data can be used with high precision in a variety of fields is now within sight.