Passive Flexible-Substrate Blast Sensor Array

Abstract

We have developed a design for a wearable passive blast sensor array to detect the peak shock experienced by personnel exposed to high energy events. The sensor is fabricated on a flexible substrate using a MEMS process. The design includes an array of sensors, each element of which is triggered at a different pressure level and which records the peak pressure by means of a permanently deformed diaphragm. The elements can be integrated with a flexible electrophoretic display or can be interrogated externally with an electronic reader. A key application is in predicting the exent of traumatic brain injury for military peronnel exposed to explosions in a battlefield environment. Peak blast information can assist in prioritizing and determining the appropriate battlefield treatment. The flexible substrate allows integration into personal armor or clothing and the passive nature of the sensor ensures a very long shelf life and reduces cost and maintenance. Details of the sensor designs and process flows for their fabrication are described. Prototype sensors have been fabricated and the fabrication characterized. Also included are simulation results for the preforamnce of the arrays. Finally, preliminary pressure blast test data for indivdual sensor elements are presented.