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Development of a Wind Tunnel Experimental Setup for Testing Multirotor Unmanned Aerial Vehicles in Turbulent Conditions

As multirotor unmanned aerial vehicles (UAVs) increase in popularity and more complex applications are investigated, the ability to reliably and repeatably perform free-flight tests is becoming increasingly important. This paper thus describes the development and characterisation of an experimental setup for testing multirotors in a wind tunnel. The open-jet wind tunnel used is 3.5 m high and the width of its walls at the output can be changed between 2.5 and 7 m in order to adjust the mean speed of the wind produced. A grid is placed in front of the jet in order to increase turbulence and a motion capture system is used to provide accurate pose information to the UAV. Wind speeds up to 5.2 and 8.6m/s are found to be possible in the wide and narrow output wall configurations respectively. The frequency content of the wind is analysed and found to provide suitable excitation for a typical UAV. Finally, results from a typical station keeping experiment are presented to demonstrate the effectiveness of the system.