Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : July 18, 2024
This study proposes a method to consider microphone array configuration for drone collision avoidance based on amplitude modulation(AM) of helicopter motion sound. As the number of microphones in the array increases, magnitude of modulation becomes larger and half width becomes narrower. Although the combination of these two factors has a great influence on the detection of helicopter motion sound, it is not known how to combine them to form a microphone array suitable for the detection of helicopter motion sound. Therefore, we consider a specific method to optimize microphone array. First, determination of the number of microphone arrays. Assume that microphone is attached to each arm of the drone. Therefore, the number of microphone arrays is equal to the number of drone arms. Second, we calculate desired microphone array directivity as half width. Third, from the prior data calculated for the number of microphones and half width and magnitude of modulation, obtain the number of microphones for each microphone spacing satisfying the conditions. Finally, the point where magnitude of modulation is the largest and the number of microphones is the smallest is obtained as the number of microphones. By following the above procedure, we can find microphone arrays suitable for detecting helicopter motion sound. From the simulation results, it is found that 6 microphone arrays, 34 microphones, 0.02 m microphone spacing, and 0.66 m microphone array length is suitable for the detection of helicopter.
