Government & Military
We have a long history of providing acoustics and vibration solution consulting for military and government agencies. One of our first projects was designing the acoustics for the United Nations Building in New York. Another early project concerned jet engine noise when jets were new to aviation.
Today, we consult on a variety of projects. We participate in Small Business Innovation Research programs to develop new acoustics and vibration solutions. Whether a town government, federal agency, military group, or transportation authority, we have the technical expertise to tackle an array of research projects. Recent work includes new microchip technology for noise reduction earplugs and ways to control vibrations of satellites in space.
Ultimately, our research has offered successful acoustics and vibration solutions to government agencies and commercial researchers.
Click to view/download.
The goal of this research is to develop a compact system for improving the understandability of speech signals sent over military radio handsets from battlefield ground forces to nearby air support personnel.
As part of an SBIR Phase II project to develop novel applications for advanced transducer materials, we developed an in-ear earphone for underwater communications for scuba divers.
Our environmental noise assessment included sonic boom analysis.
This portable acoustics system will allow military personnel to determine the shape and extent of a cave or tunnel without having to enter it.
We worked with the U.S. Air Force to develop a prototype driver for active noise reduction earplugs to protect personnel from very high sound levels.
Our consultants found ways to reduce unwanted vibration in satellites.
Design of Transducers for Underwater Communications and Hearing Protection
Naval divers, especially those who work near large ships or on underwater construction or demolition projects, are often exposed to extremely loud sounds for prolonged periods of time, putting them at risk of long-term hearing loss. The goals of this project are to improve communications between divers and the dive ship or barge, maintain stealth, and to protect the hearing of military and commercial divers working in noisy environments, such as underwater salvage and hull cleaning. The primary deliverable was a communications earphone and a noise canceling headband device for SCUBA divers, as well as noise canceling technology to be incorporated into communications devices in dive helmets.
Acoustic Cloaking with Metamaterials
Acoustic cloaking refers to a method to hide underwater objects by diverting sound waves around them. A cloak surrounding an object works by trapping waves that fall onto the cloak and guiding them around the object where they emerge on the other side. So, for example, an observer looking in the direction of a person wearing a perfect visible-light cloak would see only the light from the scene behind the person bent around her by the cloak - and not her. Thus, the cloaked person would be completely invisible. Within the last few years cloaks for electromagnetic waves (e.g. microwaves, radar) have been successfully built and demonstrated. Theoretical studies indicate that similar acoustic-wave cloaking devices should be possible and the Navy has begun to evaluate their potential to make underwater objects invisible to sonar in the current Acentech SBIR program.
This project for the U.S. Army produced a prototype system that uses vibration signals acquired on a building exterior to both locate and identify machinery that may be operating within the building.
SCIF Acoustic Certification
Sensitive Compartmentalized Information Facilities (SCIFs) are critical for security in government, military and private sector operations. Working with a government agency, Acentech developed a portable system to measure the acoustic isolation effectiveness of a SCIF based on the principles of architectural acoustics. The acoustic measurements are combined with similar electromagnetic data to assess the overall security of the space.
NRL Nanoscience Research Laboratory
NRL's Nanoscience Research Laboratory is a state-of-the-art facility intended for leading-edge research to support the Navy's mission. As such, it needs to meet extremely stringent vibration and noise requirements. The building includes a 5000 square foot class 100 cleanroom and twelve specialized laboratory spaces designed to accommodate ultra sensitive instruments. The specifications called for noise levels to be limited to NC-25 and floor vibration velocities not to exceed 125 micro-inches per second. The facility's location, at approximately 2900 ft east of the extended centerline of runway 01/18 of Reagan National Airport presented a unique challenge, in view of the frequent aircraft departures on this runway. The requirement to achieve the prescribed noise limit without interruption resulted in adoption of a windowless "box-in-box" design, with the most sensitive spaces located in the inner core. Meeting of the noise limits required shielding this inner core by multiple partition walls with high acoustic transmission loss, providing acoustical doors, and implementing special provisions to limit noise intrusions via the air handling systems, as well as controlling the air velocities in the duct systems.