Current Hot Areas of Acoustics

Progress is being made in all areas of acoustics, spurred on by advances in technology and increases in computing power. A few highlights of ongoing research are mentioned here.

• The increase in computational power is enabling high-resolution, three-dimensional solutions for sound fields in the ocean, atmosphere, and indoor spaces.
• Acoustic metamaterials are fabricated with sub-wavelength microstructures built into ordinary materials. The resulting acoustical properties can be unique and very different from the original materials. Acoustic cloaking, superlenses, and enhanced absorption properties have been demonstrated.
• Underwater drones, also known as unmanned underwater vehicles (UUVs), are being equipped with hydrophones for receiving and recording sound underwater. Nicknamed “hydronephones”, these autonomous instruments have great utility for long-range acoustic sensing.
• Computer programs for simulation and auralization of sound fields in rooms and of sound transmission in buildings are standard tools for architectural design and consulting. Progress is being made in bringing audio Virtual Reality into the mix through the combination of real-time signal processing and user interaction and multimodal human-machine interfaces.
• The noise in hospitals is a top complaint of patients, staff, and visitors. Many sources contribute to hospital noise sources, including HVAC noise, equipment noise from machines such as MRI units, alarms, PA systems, and human speech. Researchers are working with hospitals to develop and implement noise control programs.
• Technology and data processing are being pushed in the effort to clean up discarded underwater WWII-era munitions. Various signal processing tools and algorithms for feature extraction and automatic target detection are used in the process of detecting and classifying underwater unexploded ordnance.
• Acoustics is becoming increasingly important in the Arctic as the rapid loss of sea ice in the arctic circle leads to an increase in human activities. Active areas of research include multipurpose acoustic networks in the Arctic that support the passive monitoring of underwater sound, the use of acoustics to track marine mammals and evaluate their responses to industrial noise, and the use of high frequency acoustics to detect and quantify oil layers.