Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Using sound waves for remote bomb detection

A remote acoustic detection system designed to identify homemade bombs can determine the difference between those that contain low-yield and high-yield explosives.

That capability – never before reported in a remote bomb detection system – was described in a paper by Vanderbilt engineer Douglas Adams presented at the American Society of Mechanical Engineers Dynamic Systems and Control Conference on Oct. 23 in Stanford, CA.

A number of different tools are currently used for explosives detection. These range from dogs and honeybees to mass spectrometry, gas chromatography and specially designed X-ray machines.

“Existing methods require you to get quite close to the suspicious object,” said Adams, Distinguished Professor of Civil and Environmental Engineering. “The idea behind our project is to develop a system that will work from a distance to provide an additional degree of safety.”

Adams is developing the acoustic detection system with Christopher Watson and Jeffrey Rhoads at Purdue University and John Scales at the Colorado School of Mines as part of a major Office of Naval Research grant.

The new system consists of a phased acoustic array that focuses an intense sonic beam at a suspected improvised explosive device. At the same time, an instrument called a laser vibrometer is aimed at the object’s casing and records how the casing is vibrating in response. The nature of the vibrations can reveal a great deal about what is inside the container.

“We are applying techniques of laser vibrometry that have been developed for non-destructive inspection of materials and structures to the problem of bomb detection and they are working quite well,” Adams said.

In the current experiments, the engineers created two targets. One used an inert material that simulates the physical properties of low-yield explosive. The other was made from a simulant of high-yield explosive. They were fastened to acrylic caps to simulate plastic containers. Mechanical actuators substituted for the acoustic array to supply the sonic vibrations. The laser vibrometer was focused on the top of the plastic cap, corresponding to the outside of the bomb casing.

The tests clearly showed differences in the vibration patterns of the two caps that allow the researchers to distinguish between the two materials (hydroxyl-terminated polybutadiene polymer embedded with 50 percent and 75 percent by volume ammonium chloride crystals).

At the conference, Adams also showed a video of another test of the acoustic technique that showed it can differentiate between an empty container, one filled with water and one filled with a clay-like substance. The test used one-gallon plastic milk containers. In this case, the acoustic waves were produced by a device called an air driver. The empty jug had the largest vibrations while the jug containing the clay-like material had the smallest vibrations. The vibrations of the water-filled jug were in between.

The researchers have established that the best way to detect the contents of devices made of rigid material like metal is to use short ultrasonic waves. On the other hand, longer subsonic and infrasonic waves can be used to penetrate softer materials like plastics. Adam’s colleagues at Purdue are studying frequencies that can penetrate other materials like cloth.

The project is part of a $7 million multi-university research initiative led by North Carolina State University and funded by Office of Naval Research grant N00014-10-1-0958.

Visit Research News @ Vanderbilt for more research news from Vanderbilt. [Media Note: Vanderbilt has a 24/7 TV and radio studio with a dedicated fiber optic line and ISDN line. Use of the TV studio with Vanderbilt experts is free, except for reserving fiber time.]

David F. Salisbury, (615) 322-NEWS

David F. Salisbury | Vanderbilt University
Further information:

More articles from Interdisciplinary Research:

nachricht Lego-like wall produces acoustic holograms
17.10.2016 | Duke University

nachricht New evidence on terrestrial and oceanic responses to climate change over last millennium
11.10.2016 | University of Granada

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>