• 2023-07-12

Optimizing gamma-ray sensor size for drone applications

Heavy-duty drones have made it possible to fly with large gamma-ray spectrometers that weigh several kilograms. Moreover, they can be purchased at an affordable price. These large drone-borne gamma-ray detection systems are used to map the naturally occurring radionuclides potassium, uranium, and thorium. 

Such platforms have the advantage that they can be deployed over terrain that is difficult to access while still maintaining a high spatial resolution. In contrast to drone-borne radioactive pollution studies, the naturally occurring radionuclides have much lower activity and, therefore, require longer integration time, slower flying speed, or a larger detector to determine the spatial radionuclide distribution effectively. Therefore, the question arises: What is the minimum practical detector size required to successfully map naturally occurring radioactivity when using drones?

UAV with gamma-ray spectromter
Comparison of UAV-borne thorium maps

Medusa has performed a study in which the MS-2000, MS-1000, and MS-350 were mounted simultaneously on a large drone. The results of this research are convincing: all three detectors could accurately characterize the radionuclide distribution in the area. And it was shown that the measurement results can be used to predict the sand and clay fraction of the topsoil in the field. This study has proven that if the survey execution is optimized, even small sensors, such as the MS-350, can characterize the soil in an area. 

Read the full article