Low-Altitude Sensing of Urban Atmospheric Turbulence with UAV

Abstract

The capabilities of a quadcopter in the hover mode for low-altitude sensing of atmospheric turbulence with high spatial resolution in urban areas characterized by complex orography are investigated. The studies were carried out in different seasons (winter, spring, summer, and fall), and the quadcopter hovered in the immediate vicinity of ultrasonic weather stations. The DJI Phantom 4 Pro quadcopter and AMK-03 ultrasonic weather stations installed in different places of the studied territory were used in the experiment. The smoothing procedure was used to study the behavior of the longitudinal and lateral spectra of turbulence in the inertial and energy production ranges. The longitudinal and lateral turbulence scales were estimated by the least-square fit method with the von Karman model as a regression curve. It is shown that the turbulence spectra obtained with DJI Phantom 4 Pro and AMK-03 generally coincide, with minor differences observed in the high-frequency region of the spectrum. In the inertial range, the behavior of the turbulence spectra shows that they obey the Kolmogorov–Obukhov “5/3” law. In the energy production range, the longitudinal and lateral turbulence scales and their ratio measured by DJI Phantom 4 Pro and AMK-03 agree to a good accuracy. Discrepancies in the data obtained with the quadcopter and the ultrasonic weather stations at the territory with complex orography are explained by the partial correlation of the wind velocity series at different measurement points and the influence of the inhomogeneous surface.

A Novel Data Credibility-based Machine Learning Approach for UAV Capability Evaluation

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Sensing atmospheric flows in aquatic environments using a multirotor small uncrewed aircraft system (sUAS)

“…The latter wind sensing technique can be adapted for various ascent rates and could also prove useful for measuring wind uctuations required to infer atmospheric turbulence. [25][26][27] Rigid body models have been used to estimate wind velocity in the lower atmosphere ascending at various rates. 25 Efforts to explore the feasibility of employing multirotor sUAS wind sensing capabilities for resolving atmospheric ow variations in aquatic environments are just beginning.…”

High-Resolution Profiling of Atmospheric Turbulence Using UAV Autopilot Data

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