Monitoring Device Helps Commanders Get Under Troops’ Skin

By Fred W. Baker III
American Forces Press Service

WASHINGTON, June 18, 2009 – Military leaders have long relied on “eyeballing” their troops to ensure they do not fall victim to harsh combat or rigorous training conditions.

Anthony Kares with the U.S. Army Research Institute of Environmental Medicine demonstrates the Warfighter Physiological Monitoring System, a remote, wireless system that can monitor a soldier’s heart and breathing rates, body position, activity and skin and core temperatures. DoD photo by Fred W. Baker III   (Click photo for screen-resolution image);high-resolution image available.

Face-to-face with the troops, they assess how they are holding up, looking for signs of heat injuries, fatigue and dehydration. They listen to their speech and look into their eyes. They feel their skin and watch their gait.

But often, by the time symptoms show on the skin’s surface, medical intervention is needed and the troop is, in effect, out of the fight.

These injuries can delay training. In combat, they can bring operations to a screeching halt. Sometimes they prove fatal.

Scientists at an Army research lab here, though, have designed a system that could allow leaders to eyeball what’s going on under the skin of their troops.

The Warfighter Physiological Monitoring System, designed by scientists and researchers at the U.S. Army Research Institute of Environmental Medicine, smacks of science fiction, allowing commanders to simply glance at a computer screen for a check on the vital statistics of each of their troops.

The remote, wireless system can monitor a soldier’s heart and breathing rates, body position, activity and skin and core temperatures.

While it’s not a replacement for one-on-one interaction, the device can give commanders and unit medics an additional tool to measure their troop’s health status, scientists said.

“The idea … is a commander can look at his guys and understand what level of risk they’re at,” said Mark Buller, a research physiologist at the lab. “It will give him the tools to make decisions so that he can minimize injuries.”

The system is designed around a sensor that looks much like popular heart-rate monitors worn by serious athletes. The device’s band straps around the back and chest, and the sensor snaps over the sternum. A shoulder strap keeps it from slipping down the torso.

A transmitter shaped into a small pill about the size of a multivitamin must be swallowed to transmit core temperature to the system.

Data is collected and transmitted from the sensors to a computer. The display shows the sensor wearer’s health statistics.

The system offers a range of uses in combat. Line medics would be able to instantly assess a troop’s health during a firefight. Without actually seeing the troops, on the computerized display the medic could monitor if they are up fighting, or down. If the troop is a casualty, the medic could see instantly if they are dead or alive, allowing for a faster triage of care. Commanders could monitor the vital signs of their entire unit.

But, so far, the monitors have been used only in testing to gather data on the stressors and strains of training and combat.

Last year, a Marine squad deployed to Iraq wore the systems, helping researchers at the lab collect data to understand the effects that the service’s current uniforms, combat loads and body armor have on core temperature.

“The physiology that we’re getting back … is beginning to look as if they were semi-encapsulated in chemical-biological gear,” Buller said. “The amount of clothing and equipment is really driving the risk higher.”

In fact, the study showed the Marines experienced significant thermal-work strain after two hours of foot patrol in 100-degree plus temperatures carrying full combat loads and wearing body armor. The Marines’ core body and skin temperatures reached levels that put them at a 50 percent risk of succumbing to heat exhaustion.

By monitoring thermal, hydration, and activity levels of troops, the scientists can begin to understand at what point someone is getting fatigued and becomes more susceptible to injuries, Buller said.

The data can then be put into a medical model that can help predict if, and when, a troop is going to be a heat casualty.

Officials at the lab hope to use the system on more soldiers and Marines deploying to combat. The Army is looking at fielding the system to its Special Forces. And the lab is using the system in tests with other foreign militaries.

Beyond its ability to help keep soldiers safe, though, the system also offers the benefit of knowing how hard commanders can push their troops in training.

Anthony Kares, a lab technician at the institute, likened the system to those trainers use for professional athletes to ensure maximum effort.

Officials from the 101st Airborne Division have looked at the monitor to see if it can be used to push their troops harder during training, Kares said. And the U.S. Army Rangers want to put the data the lab has collected into a model that will help them vary the load and pace of their road marches based on the conditions to ensure peak performance.

“Similar to the way professional athletes are trained, we can also tailor this to optimize training for the soldier in different environments,” Kares said.

The system could also be employed at military schools where there are higher risks of heat casualties and in basic combat training where the troops have less physical conditioning.

Researchers at the lab are working to improve the system, making the chest sensor smaller for a better fit under body armor. They are helping to refine the user interface to show only the data needed, depending on the user. And they are working on a less invasive way to gather core temperature data rather than having the wearer swallow the sensor pills. The pills could not be easily used on a large scale or in field situations, researchers said.

Still, the data collected already by the system has proved valuable to research efforts. And, Kares said, he envisions every soldier wearing the monitor in the next 20 years.