INDYCAR drivers this season will be equipped with a triaxial MEMS (micro-electromechanical system) accelerometer recently introduced by Analog Devices, Inc. (ADI). The device, ADXL377, improves on an earlier ADI accelerometer that INDYCAR drivers wore during this year’s INDY 500.
The accelerometer, located in drivers’ communications earpieces, measures the acceleration of high-impact shock and vibration events triggered by collisions during practice, time trials, and races. It has a 1600-Hz bandwidth, a ±200 g measurement range and an analog output that continuously captures impact data. It eliminates the need for placement of orthogonal sensors, and ADI says it takes about one-fifth the board space of designs based on multiple, single-axis accelerometers.
With a MEMS sensor in each driver’s earpiece and another in the car chassis black box, INDYCAR engineers have a closed-loop system that can measure the effects of impact on both the driver and the car. Jeff Horton, director of engineering at INDYCAR, says his team expects to place the new accelerometer closer to the ear canal opening, which should result in a more accurate reading. “In the past,” he says, “we had to use three separate ICs in each ear to obtain the same data.”
In addition to INDYCAR, ADI sees potential for the new device in soccer, football, and other contact sports, where the detection of concussive forces can reveal indictors of Traumatic Brain Injury (TBI).
“With TBI now a serious medical concern in many facets of life – from athletes and workers to military personnel – ADI is helping customers design smaller, more accurate and simpler impact systems,” says Mark Martin, vice president and general manager of ADI’s MEMS/Sensors group. “Because so many of these applications require extreme mobility, the ability to eliminate orthogonal sensors while simultaneously lowering energy consumption means that these battery-operated devices can run longer between charges.”