Suitability of thermal UAV data to detect stones and artificial objects in agriculture

Stones on agricultural land can cause serious damage to agricultural machinery, when they are getting inside the machinery. This phenoma is especially pronounced in regions with high frequency of stones occurring on agricultural lands, e.g. in glacial morainic landscapes, as they occur in northern Germany. Therefore, stones must be removed from farmland several times a year. A worfklow for drone-based detection of stones is currently under development at the Geoecology department of MLU Halle to assist solving this problem.
With our workflow, we demonstrate the particular suitability of UAS-based thermal data to differentiate between stones and soil surface on agricultural lands. Thermal inertia effects can be used to make significant temperature differences between stone and soil detectable. Which enables precise stone detection through UAS based thermal imaging. We have conducted extensive laboratory testing to investigate the suitability of thermal imaging to detect stones and to find the optimal pre-requisite for thermal UAV flights.