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A Passive Cloud Detection System for UAV: Analysis of Issues, Impacts and Solutions

Lightweight unmanned aerial vehicles (UAVs) are highly susceptible to the presence of clouds. In contrast to other UAVs or airplanes, clouds directly pose a danger to their structural health. Furthermore, clouds indicate other weather phenomena appearing in their vicinity, such as turbulences or icing. Additionally, the stringent platform limitations of lightweight UAVs, for example, mass and energy consumption do not allow the use of the classic on-board weather sensor, the weather radar. Therefore, a passive cloud detection system for on-board use, based on an imaging sensor, was proposed and developed. The focus of this paper lies on the challenges of the used measurement methods. An analysis of each step identifies the issues during cloud detection and mapping. Calculations and tests in virtual and real environments show their impacts. Eventually, solutions or mitigations are presented respectively.