Helicopter main rotor angular velocity analysis by laser Doppler velocimetry: simulation and experimental results

In this paper, the three different motions of a helicopter blade are studied by the laser Doppler velocimetry (LDV) technique. Consequently, a calculation is performed by utilizing the Simulink simulation of Matlab software. All noises, including optical, electrical circuit, and experimental environment noises, are considered. Furthermore, the temporal and frequency behavior of the final signal are illustrated for uniform rotation of the helicopter blade. The results demonstrate that there is acceptable agreement between the frequencies calculated by the theoretical, simulation, and experimental analyses, which shows the capability of LDV in measurement of helicopter main rotor angular velocity.