A man stands in the middle of a large room with all four walls covered in 2-foot thick, triangular-shaped wedges of foam. Any noise he makes is immediately absorbed by his surroundings.
This isn't a scene from the latest Halloween horror film or a high-tech recording studio. It is the new hemi-anechoic chamber located in the American Institute for Manufacturing Excellence building at the University.
The chamber, which is the largest of its kind in the Southeast, allows UA students and faculty members in the department of engineering to analyze the sounds emitted by certain objects and machinery.
Steve Shepard, an associate professor of mechanical engineering, said the hemi-anechoic chamber eliminates any echoes and acoustic reflections by using the walls and ceiling to absorb sound.
"It basically mimics an extremely large concrete parking lot," Shepard said. "An important difference, though, is that the environment is controlled and very quiet."
The chamber is surrounded by 8-foot walls filled with insulation and built on springs to prevent any outside vibrations from affecting a test inside the chamber.
Shepard said the absence of outside noise sources, such as wind and rain, allow the chamber to take precise acoustic measurements.
The chamber is currently being used on a project with the National Science Foundation to develop an acoustic sensor that could be used to locate people trapped after buildings or mines collapse.
The National Science Foundation awarded Shepard a grant of $120,000 to develop the sensor.
Shepard said the department of engineering partnered with Tuskegee University, which was awarded an additional $100,000 grant to work with the University on the sensor.
Graduate students are working with the faculty members on developing the sensor, he said, which could replace the microphone technology currently used in emergency situations.
Shepard said a single microphone can detect the strength of a sound but not the location of the source, and though multiple microphones can help find the source, they are bulky and take time to set up.
"We also hope to be able to determine how far it is to the sound source using sophisticated signal processing techniques, which are also being developed at UA," Shepard said.
The creation of a single sensor would decrease or eliminate the amount of set-up time, Shepard said, and would allow rescuers to begin using the equipment more quickly.
Undergraduate students working on the Formula Society of Automotive Engineers' project were allowed to use the chamber to test their car, to see if it met the sound requirements for competition.
David Trawick, a sophomore majoring in mechanical engineering, said the Formula team performed tests in the chamber to see if the car met the 110-decibel requirement.
"We used the chamber to see if there were any other parts of the car resonating noise other than the muffler, because it helps us with the development of our project," Trawick said.
Shepard said the chamber was also used for a short project with the Alabama Productivity Center to measure the noise a short bow radiated.
Shepard said a proposal under review by the National Science Foundation would allow undergraduate summer interns to use the chamber.
The hemi-anechoic chamber was purchased and built using funds from the College of Engineering dean's office and the Alabama Institute for Manufacturing Excellence.
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