An Appraisal Of Large-Scale Particle Tracking With Uncrewed Aerial Vehicles

Camera technology is rapidly enhancing within the last years, which led to the availability of sophisticated technical features within consumer cameras, that could only be found in scientific set-ups earlier. The present work explores the possibilities of utilizing the potentials of commercially-available camera drones as moving cameras for large-scale particle tracking velocimetry. We made use of the glare-point particle tracking approach introduced by Kaiser & Rival (2023), where only a single camera and natural illumination, e.g. the sun, could be used. The set-up demonstrated full suitability for large volumes in the order of 10-100 m³. The frame-to-frame camera movement, caused by the slight movement of the drone could be quantified and corrected by an imaged-based approach. The calibration strategy could be simplified due to the fixed set-up in the camera drone. The limits introduced through the tracer size and uncertainty caused by the glare-point approach are discussed accordingly. For the presented magnification and camera set-up given by the DJI Mini 3 pro, the limit in height can be determined when the two most dominant glare points collapse to one, which happened well above 10 m for the present set-up. The equipment together with the glare-point particle tracking approach is best suited for flow information extraction at large-scale facilities or difficult accessible terrain, where the current set-up could depict its strengths.