Helmet sensors to record blast exposure in at-risk soldiers
Explosions in the battlefield can cause all sorts of injuries that are immediately apparent, but they can also cause ones that are not. Soldiers exposed to blast pressure and shock waves can go on to develop traumatic brain injury (TBI) well after the danger of more visible damage has passed. Looking to make faster and more informed decisions on this front, the US Navy is developing small sensors that, when paired with specialized scanner, can quickly convert blast pressure into a clear signal of whether of not that soldier should stand down.
As it stands, the US Department of Defense's approach to dealing with explosions in the battlefield is commanding everybody within 50 m (165 ft) to stand down for 24 hours, and then go through a mandatory medical checkup to prevent repeated exposure to dangerous blasts. But in the view of Timothy Bentley, program manager of the Office of Naval Research's (ONR) Warfighter Performance Department, these guidelines have a couple of drawbacks.
One is that some forward operating bases are as small as 100 meters (330 ft) from end-to-end, meaning that an explosion on site would require half of the officers present to stand down. Another is that the effectiveness of using a regular medical exam to detect signs of TBIs within 24 hours is questionable anyhow.
So the ONR is funding the development of what is says will be an important advancement in the area. Dubbed the Blast Load Assessment Sense and Test (BLAST), the solution comprises three parts in total, with the first two designed to give medics on-the-spot guidance as to whether a soldier can continue the fight.
Coin-sized sensors that can withstand explosions would be worn on helmets or body armor and capture blast pressure in the event of an explosion. A specialized scanner, possibly a handheld device similar to a barcode scanner or a stationary version resembling an airport metal detector, would then download the pressure data and use an algorithm to turn it into a "go or no-go" reading – meaning a simple yes or no answer as to whether the soldier can remain in action.
If the answer is no, then the third part of the system comes into play, a neurofunctional assessment tool around the size of a computer mouse. The patient holds this in hand as it delivers vibrations in various patterns that stimulate feelings in the fingertips, and by checking whether or not the soldier feels those sensations, medics can determine whether or not TBI symptoms are at play.
The BLAST sensors are in a testing phase in the laboratory, but within a year and a half, the ONR hopes to test the technology on field mannequins and then on Marines during training exercises.
"Together, the components of BLAST can enable us to designate a pressure threshold number for when someone is at risk for TBI and needs to stand down for more advanced testing or medical care," said Dr. Laila Zai, a scientist with ARA, a research and engineering company helping to develop BLAST. "Think of a speedometer. Whether you're going too fast or slow depends on road conditions, and is indicated by the speed limit. BLAST determines a safe 'speed' for the brain."
Source: Office of Naval Research