Directional infrasound sensing using acoustic metamaterials

Area of Science:

• Acoustics
• Materials Science
• Geophysics

Background:

• Infrasound waves travel long distances, valuable for monitoring natural and anthropogenic events like volcanic eruptions and nuclear explosions.
• Conventional infrasound monitoring relies on pressure sensors, which lack directionality, necessitating large sensor arrays for source localization.
• Large infrasound arrays are often impractical due to space, power, and deployment constraints in diverse environments.

Purpose of the Study:

• To present the theoretical foundation for a compact infrasound direction of arrival sensor.
• To introduce a novel sensor design utilizing acoustic metamaterials.
• To enable efficient infrasound source localization in previously challenging locations.

Main Methods:

• Development of theoretical principles for a compact infrasound sensor.
• Design of a sensor leveraging acoustic metamaterial properties.
• Evaluation of the sensor's capability to determine infrasound direction of arrival.

Main Results:

• The proposed sensor achieves direction of arrival determination.
• The sensor's footprint is significantly smaller, orders of magnitude less than traditional arrays.
• This compact design enhances deployment feasibility in restricted areas.

Conclusions:

• Acoustic metamaterials provide a viable basis for compact infrasound directionality sensors.
• The developed sensor design overcomes limitations of conventional large-aperture arrays.
• Further research is recommended to explore advanced applications and refine the technology.