Drone anemometry of atmospheric winds—A review

The low altitude economy presents new opportunities for urban mobility with drones and air taxis offering solutions to traffic congestion and access to hard-to-reach areas. These opportunities come with the same challenges as in civil aviation: the atmospheric boundary layer (ABL) gives rise to wind gusts and turbulence, leading to sudden displacements of the low-altitude vehicles from the planned trajectory. Hence, a reliable estimation and prediction of wind conditions is paramount to safe drone and air taxi operations. Drones offer an attractive alternative to expensive stationary platforms for wind monitoring in the lower ABL. This article reviews the status, challenges, opportunities, and alternatives to drone-based wind anemometry. Aspects include the wind measurement and estimation of urban terrain, performance metrics of anemometers, model-based wind speed measurement, and machine learning algorithms for atmospheric wind prediction. Already the attitude of the hovering and cruising drones allows to infer the wind velocity. The accuracy of drone wind measurement may be further augmented with various anemometers such as ultrasonic, thermal, hot wire, and pitot tubes. This article exemplifies the potential of drone anemometry for urban wind prediction, for measuring wind profiles in remote areas of wind turbines as well as a tool for boundary layer meteorology and assessment of gusts in harsh weather conditions.