Interfacing a Microelectromechanical System (MEMS) Sensor Array for Traumatic Brain Injury Detection with a Microcontroller

Report No. ARL-TR-6240
Authors: Timothy C. Lee and Luke J. Currano
Date/Pages: October 2012; 38 pages
Abstract: Traumatic brain injuries (TBIs) result from exposure to high accelerations and are a serious threat to Soldiers in close contact with improvised explosive devices as well as sports players who are frequently involved in collisions. To improve TBI detection, the U.S. Army Research Laboratory (ARL) has developed a sensor small enough to be mounted in the ear. The sensor consists of an array of 3-axis microelectromechanical system (MEMS) acceleration threshold switches with different sensitivities that move to contacts under acceleration and complete a circuit. Previously, the outputs, which were voltage levels, required an analog-to-digital converter, but the implementation of the mechanism introduced a delay of 100 μs between samples. This delay has caused the loss of data from switch closures that last less than 100 μs, so the sensor was redesigned with digital outputs, and a new program was developed. Clocked signals were used to simulate sensor data, and tests showed improved delays of 3 μs to 10 μs.
Distribution: Approved for public release
  Download Report ( 0.828 MBytes )
If you are visually impaired or need a physical copy of this report, please visit and contact DTIC.

Last Update / Reviewed: October 1, 2012