Horizontal and vertical wind speed sampling using multirotor UAS aircraft

The utilization of multirotor UAS aircraft for atmospheric data collection is an expanding field, and one method employed for measuring atmospheric wind speed is the tilt angle method. This method correlates the tilt angle assumed by the multicopter during hovering to compensate for aerodynamic drag forces with the atmospheric wind.
At the Umweltphysik Group of Uni Tübingen, a cost-effective and easily replicable calibration method has been devised and tested. However, this approach overlooks the crucial vertical component of the wind, essential for calculating vertical turbulent fluxes.
To address this limitation, a follow-up study proposes an analytical approach that involves calibrating relationships between wind speed and tilt angle, motor RPM and tilt angle, as well as vertical wind speed and RPM. The necessary data for this calibration can be obtained through telemetry from an open-source flight controller's log files.
Accurate calibration of these relationships is ensured through real-world flight testing to maintain precision. Indoor tests or wind tunnel experiments might yield biased results due to interactions with walls, failing to accurately represent the aircraft's outdoor aerodynamic behavior.
Considering environmental parameters is vital, as evidenced by notable differences between calibrations conducted in winter and summer. These variations underscore the necessity of accounting for environmental influences.
Subsequently, the method will undergo further validation by flying the aircraft in close proximity to a sonic anemometer to assess its accuracy in measuring atmospheric parameters.