High-G MEMS help detect concussions

May 25, 2012 // R. Colin Johnson

Sports-related concussions have skyrocketed in the U.S. with over 3.8 million reported each year. New MEMS sensors small enough to be mounted inside an athlete's helmet, for example, could perform early detection of symptoms, giving doctors time to administer preventative therapies.

"Starting about a year and a half ago we started getting requests for MEMS accelerometers to detect concussions," said Wayne Meyer, MEMS marketing and applications manager at Analog Devices. "Concussive forces start at around 60 Gs and go up to about 120 Gs, but most applications also want to provide some headroom so the sensor never saturates,” Meyer added. “So we built ours to sense plus or minus 200 Gs."

Using high-G sensors for early detection of concussions could drastically reduce injuries, according to the American Association of Neurological Surgeons, since most injuries occur because treatment is delayed. More than 75 percent of concussions go undiagnosed, eventually contributing to over 30 percent of head trauma deaths in the U.S., according to the Centers for Disease Control and Prevention. Early detection also could cut medical bills and lost productivity, which is estimated to exceed $76 billion annually.

Analog Devices, which already produces single-axis, high-G accelerometers used to detect concussions in IndyCar drivers, recently redesigned their high-G sensor into a single chip, allowing it to fit inside football and other sports helmets. The high-G MEMS accelerometer measures 3-by-3-by-1.45 mm, making it small enough to fit inside a helmet-mounted earpiece to measure head trauma. The ADXL377 draws only about 300 microAmps, making it suitable of battery operation.

"There are many sports where high-G accelerometers could be used to detect concussions,” said Meyer. “Football and skateboarding come to mind immediately, but even cycling, water sports and snow skiing are all candidates.” Industrial and aerospace applications include high-G MEMS sensors used along with impact tools and other machinery, he said

Recent high-profile NFL incidents involving repeated head trauma have upped the ante for concussion detection solutions. For instance, after former NFL linebacker Junior Seau's recent suicide has been linked to possible head trauma over the course of a long career. Other former NFL players have joined in a lawsuit against the lead claiming it ignored the health and safety of players.

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December 15, 2011 | Texas instruments | 222901974

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