Towards laser-doppler-vibrometry with UAVs - the effect of wind disturbances on the position of a mirror attached to a drone

Recently there has been an interest in using laser Doppler vibrometers (LDVs) in combination with multirotor drones for structural health monitoring (SHM) of large structures like bridges or wind turbines. In order to easily position the measurement beam of the LDV on any point of the structure, a new measurement system is being developed for redirecting the beam using a mirror carried by a drone. A tracking system will have to be designed that will keep the laser beam centered on the mirror. However, the wind’s influence on the movement of the mirror is unknown and consequently the requirements for the tracking system are unclear. In this work, tests with a 3D anemometer and DJI’s Matrice 300 are carried out outdoors to determine the drone’s dynamic response to wind fluctuations. The drone’s angular movement correlates well with the wind speed, indicating the validity of the tests. The findings give a clear overview of the disturbance rejection performance of this commercially available drone operating under realistic wind conditions, using high-resolution wind measurement data and can inform the development of requirements for applications involving a directed beam aimed at a drone.