Thursday, January 13, 2005

"SENSORS: $200 sensor detected South Asia quake"

A novel electronics architecture enabled a seismic sensor costing nearly one-fiftieth that of more elaborate ones to detect the recent tsunami-causing earthquake in South Asia. While today's seismic detectors cost upward of $10,000 each, making them impractical to deploy in poor or rural areas such as those devastated by the recent tsunami, the new detector can be built for under $200. "My detector does not replace those expensive seismic detectors, which have many more functions than my sensor. But my design can sense earthquakes and volcanic activity much less expensively," said Randall Peters, chairman of the physics department at Mercer University (Macon, Georgia). "Right now my detector is set up to try to sense the Earth's acceleration to test a theory of James Shirley's [a scientist at NASA's Jet Propulsion Laboratory]. I was monitoring the instrument for that purpose when it jumped significantly and continued above the background noise for a period of more than two hours." By checking the exact timing, Peters confirmed that even though his sensor was almost halfway around the world, the device provided early warning just before the Indian Ocean earthquake that caused the region's devastating tsunami. His sensor, based on a precision pendulum-like architecture, moved two thousandths of an inch, with a period of oscillation of 30 seconds for two hours.