Sound localization in an anisotropic plate using electret microphones

Area of Science:

• Materials Science
• Acoustics
• Engineering

Background:

• Acoustic source localization in anisotropic plates without velocity profile knowledge is challenging.
• Existing time-of-flight methods require numerous high-sampling sensors, limiting practical efficiency.
• Non-time-of-flight methods offer lower sensor counts but sacrifice accuracy.

Purpose of the Study:

• To propose a novel, efficient acoustic source localization technique for anisotropic plates.
• To reduce sensor requirements and data handling complexity compared to existing methods.
• To enhance localization accuracy using fewer, lower-sampling rate sensors.

Main Methods:

• Utilized four low-sampling rate electret sensors arranged in two clusters.
• Employed attenuation analysis within a specific frequency band for localization.
• Incorporated a stethoscope as a physical filter to delineate the dominant frequency band.

Main Results:

• Successfully localized acoustic sources in an anisotropic plate with only four sensors.
• Demonstrated that accuracy is dependent on the distinction of the dominant frequency band.
• Experimental validation on an airplane composite nose confirmed the method's viability.

Conclusions:

• The proposed method offers a more efficient and accurate approach to acoustic source localization in anisotropic plates.
• Reduced sensor count and sampling rate make the technique more practical for real-world applications.
• Frequency band delineation is crucial for optimizing the accuracy of this novel localization technique.