Experimental method for unmanned aerial vehicles

The aim of this work was to design and analyze a method for measuring the lift-drag ratio of flying vehicles with fixed-wing configuration in a weight category up to 25 kg in order to achieve as accurate results as possible considering the described category. In the normal design process of new machines, the performance is known only from theoretical calculations or from numerical simulations or from the measurement of parts of the structures in an aerodynamic tunnel. The performance measurement method described in this work after proper use will provide complete information about the prototype's performance under real-world conditions while theoretical performance always needs to be verified despite today's considerable progress in computing methods. The proposed method was applied to a simple model of the aircraft for which flight performance was theoretically calculated. After including sensors inaccuracies, external weather conditions and other disruptive effects, it was possible to analyze the behavior of the measuring method and assess whether it is suitable, for example for measuring new aircraft prototypes. It was necessary to take into account the small dimensions of the fuselage, where measuring sensors and control electronics are located, the small weight of the aircraft, and thus, keep the mass of the sensors negligible respectively to the total mass of the aircraft. The result of the work is a description of the flight tests, as well as the layout of measuring devices located on board the aircraft. Furthermore, an analysis of the results obtained by this method was carried out when applying the intrusive effects corresponding to the normally achievable atmospheric conditions. Despite reduced accuracy in the range of lower airspeed, the performance of the aircraft can be measured with very good accuracy. The results are well usable for the design of small unmanned aerial vehicles.