Soldiers, Wearables and Sensors; Where Next

The soldier of the near-future may more resemble a robot than a humanoid: wrapped in an Iron Man-style exoskeleton and bristling with sensors and electronic devices from his eyes and ears to the heels of his boots, a node on a network with hyper-awareness of the battlefield situation and artificial intelligence-supplemented decision-making. Rick Adams scans a few of the emerging wearable technologies.

GPS and motion sensors. Barometers and chemical detectors. Body cams. Microphones. Speech recognition algorithms. Bio measurement electrodes. Electronic tattoos. Digital dog-tags.

Next-generation soldiers will be walking computers. With access to nearly limitless augmented reality information. And augmented physical strength.

It’s all part of the new “wearables,” in which “typing, clicking and touching” is going to be replaced by “tapping, winking, blinking, tracking, talking and gestures,” according to futurist authors Robert Scoble and Shel Israel. “It will move technology from what we carry to what we wear.”

Predictions are that 350 million wearable devices such as FitBit exercise monitors and Apple wristphones will be in use worldwide this year. In the military, wearables are much more than monitoring pulse rate and sleep cycles. Researchers are seeking to enhance soldier awareness, performance, safety and survivability, and in the process redesigning everything he (or she) puts on their body. There are hundreds, perhaps thousands of developments, mostly pursuing the consumer market but many of those with military operations and training potential.

Following are just a few of the intriguing projects being funded.

Smarter Bodies

“We are killing more Marines and soldiers in training than in combat,” said LtCol. Warren Cook Jr. of the US Marine Corps at the Global Body Computing Conference. Since 2001, more than 1,400 Marines have died in training, compared to about 1,250 combat deaths over that time. “Why does that happen? A lot of times it is fatigue,” explained Cook, who is a battalion commanding officer in the 1st Marine Division, stationed at Camp Pendleton, California.

Soldiers hauling heavy gear in high optempo environments can easily get too hot. So the US Army Research Institute of Environmental Medicine (USARIEM), in a joint project with MIT Lincoln Laboratory and a Marine Corps expeditionary rifle squad, is combining a wearable sensor with an algorithm to interpret biological markers for signs of pending heat stress.

FitBit is inadequate to the military task, according to USARIEM principal investigator Mark Buller. “A lot of the algorithms are very broad, very general, and you have a lot of error,” he said. And there are inherent security issues. “They are locked into cloud storage and cloud processing. Do we really want to put information on the health state of our soldiers into the cloud? That is an area of concern.”

Last year, an Australian university student discovered that global positioning system (GPS) data points from personal fitness devices such as FitBit, uploaded to an online “heat map,” might reveal the favorite jogging paths of military personnel based in remote locations of Afghanistan, Iraq and elsewhere. Col. Andrew Hall, director of the Army Cyber Institute at the US Military Academy (West Point), noted, “You start to look at the ways that we try to make the systems easier for consumers, to try to make things more efficient. And then you really find that efficiency is an area of weakness and something that is exploitable.”

A London-based company called Bodytrak has developed an 18-gram, precision monitoring device that is worn in the ear – the one body site from which all of an individual’s vital signs (core body temperature, heart rate, oxygen and motion) can be measured accurately. Data is fed to a cloud-based analytics platform. Bodytrak also incorporates two-way communications and passive noise cancellation to prevent noise-induced hearing loss.

The Defense Advanced Research Projects Agency (DARPA) is funding research by San Francisco-based Profusa that uses an “implantable” seed-sized biosensor to measure oxygen and lactate acid, which can reveal if someone is getting sick before they feel any symptoms.

A Netherlands firm, Offroad Apps & Things, is working with the Dutch Ministry of Defence to develop Bluetooth wireless, soldier-worn sensors to help casualty care nurses monitor the wounded on the battlefield. Vera Pijl, who co-founded the firm, told MS&T that their background in pattern recognition from large data sets for NATO and others can be applied to analysing vital signs such as heart and respiration rate, then relaying the information through the medical care chain.

To protect vulnerable recruits and enable healthy soldiers to enhance their performance, the US Army wants to use biosensor data to create “precision training.” LtCol. James McKnight, environmental science officer at the Military Operational Medicine Research Program at Fort Detrick, Maryland, suggested that training tailored to individual needs and capacities “is going to require a huge cultural shift with tactics, techniques and procedures. But it’s going to be a useful tool to monitor for readiness and for us to be deployable.”

SolePower SmartBoots help dismounted soldiers be safer and more efficient by increasing their situational and physiological awareness even when access to power is scarce - and the system is also self-powered by a kinetic charger. Image credit: SolePower.

Smart Boots and Battery Alternatives

The typical warfighter carries at least 60 pounds of gear, and some specialists may be staggering under as much as 130 pounds. Radios, night vision equipment, laser target locators, Maglites, GPS receivers, binoculars, beacons, rifle scopes, etc. Most of these are reliant on batteries (which often requires carrying backup batteries for missions of 72-96 hours).

An alternative power startup that has caught US Department of Defense attention is SolePower, which originated in a class at Carnegie Mellon University in Pittsburgh, Pennsylvania. Their Smart Boot translates the kinetic energy of a soldier’s marching or running into about 100 milliwatts, sufficient to self-power sensors for GPS tracking, radio-frequency ID, LED lighting, temperature sensing, and even communications (though not enough to run a wearable computer, yet). Co-founder Hahna Alexander explained the system uses the compressive “heel strike” of the boots to drive continuously spinning magnets, generating alternating current which is converted to direct current via a microcontroller.

The SmartBoots can also embed inertial measurement units for gauging motion, and a change in the gait pattern between the two boots could be used to determine issues such as fatigue. Alexander told me several military boot manufacturers are very interested in incorporating the technology.

Also under investigation is “body heat harvesting,” i.e. using the temperature difference between the body and the ambient environment to drive a thermoelectric generator (TEG) capable of powering low-power wearable electronic devices such as health and environmental monitoring sensors.

Johns Hopkins University Applied Physics Lab (APL), along with scientists from the University of Maryland and the Army Research Lab, have designed “a battery in the form of a sheet,” according to Jeffrey P. Maranchi, APL programme manager. The battery uses salt water as its electrolyte medium, embedded in a resin base, which is both flexible and can be submersed. And “you can literally cut it with scissors,” said Maranchi. Unlike lithium-ion batteries, it won’t explode. They expect it will be 3-5 years before soldiers are able to deploy with a rolled sheet of all-purpose battery. The longer-term vision “is to have a ‘power fabric’ with a battery 3D-printed into a uniform or printed into gear,” Maranchi said.

Another power fabric approach uses a relatively new material, graphene, a semi-metal carbon lattice a mere atom thick. It has been called the strongest material ever tested, and efficiently conducts heat and electricity. Graphene was isolated and characterised by Andre Geim and Konstantin Novoselov at the UK’s University of Manchester in 2004. Recently researchers printed a flexible supercapacitor of graphene-oxide ink onto cotton fabric. “If you have a piece of fabric and you apply graphene on that fabric, it doesn’t only make it conductive, it also makes it stronger,” said Mohammad Nazmul Karim, a Fellow at the National Graphene Institute. Supercapacitors can be charged quickly compared to batteries and don’t lose their energy storage capabilities over time.

The Tactical Augmented Reality (TAR) headset overlays positional information within the soldier's field of view. Image credit: US Army.

Smart Helmets, Connectors and Exoskeletons

Virtual and augmented reality helmets, goggles and glasses, of which there are many, get the most attention.

One of the most promising is the Tactical Augmented Reality (TAR) system from the US Army Research, Development and Engineering Command's Communications-Electronics Research, Development and Engineering Center (CERDEC). TAR is a hands-free, night vision goggles-style head-up display (HUD) that overlays onto the soldier's field of view a tactical map, including location of friendly forces and enemies. It handles automatic geo-registration, the alignment of an observed image with a geodetically calibrated reference image. The key technological breakthrough was miniaturisation of a high-resolution display to fit into the one-inch-by-one-inch eyepiece, according to David Fellowes, an electronics engineer at CERDEC.

The eyepiece is connected wirelessly to a waist-worn tablet and to a thermal site mounted on the soldier’s rifle, showing the image of the target plus details such as range. A soldier behind a wall could lift the rifle over the obstacle and see a target via the HUD without exposing their head. Images could also be shared with other members of the squad.

With the new wearable military electronics, many still wired because of concerns about signal emissions on the battlefield, cable management becomes an issue. Switzerland-based Fischer Connectors is about to launch a miniaturised push-pull circular connector which can be used in any orientation. Unlike USB, HDMI and other standard electronics connectors, which can only be plugged in one way, the LP360 has no such “key code.” Regardless of the number of contact pins, each will touch one of the circular rings in the receptor. Fischer product manager Wim Vanheertum told MS&T the low-profile design can be built into clothing such as a vest “and will not hinder the soldier.”

Unlike Tony Stark’s full body armour “force field” Iron Man suit, most military “exoskeletons” use a simpler lightweight frame with actuators and motors, powered by a rechargeable battery. The frame fits alongside the soldier's legs and is attached to a belt around the waist; flexible hip sensors show where the soldier is located plus speed and direction. In early tests of a US Army version, called Fortis, developed by Lockheed Martin, soldiers could carry 180 pounds up stairs using minimal energy. The Russians have shown a concept for an exoskeleton promising ballistic protection from bullets and shrapnel, as well as a heads-up display. Chinese firm Norinco is designing a “power up” exoskeleton to carry over 100kg of supplies without struggle.

An international research team led by scientists at The University of Texas at Dallas and South Korea’s Hanyang University, and including Wright-Patterson Air Force Base in Ohio, has developed high-tech fibers – “artificial muscle” yarns and “twistron” electricity harvester yarns. Dr. Carter Haines, associate research professor in the NanoTech Institute at UT Dallas, told MS&T, “The twistron yarns can be embedded into clothing or exoskeletons to measure deformation, or could even recharge batteries if there is enough mechanical input. The artificial muscles are actuating/length-changing fibers which are much more similar to natural muscles (which are also bundles of fibers) than conventional bulky motors. This means we can directly integrate them into humanoid robots or exoskeletons, as well as use them to make prosthetics or orthotics.” He said they have worked on a DARPA-funded project to make “fuel-powered” artificial muscles.

Smart Integrations

The UK Dismounted Close Combat Sensor (DCCS) wearable sensor fusion programme, led by the Defence Science and Technology Laboratory and involving UK firms Roke, QinetiQ, and Systems Engineering and Assessment (SEA), uses inertial and visual navigation sensors to provide soldiers with 3D navigation data when a GPS signal is not available, such as in dense urban environments, buildings or tunnels. Using the last-known GPS location, DCCS combines information from visually tracked features captured by a helmet camera and inertial sensors. The programme, expected to enter service in the 2020s, is also developing a new thermal sight to extend detection range. The DCCS team considered 252 “fledgling technologies” in their sensor quest.

Rheinmetall Defence has developed a 2.0 version of its Gladius soldier system, based on lessons learned from the German Infanterist der Zukunft – Erweitertes System (IdZ-ES), ie, Future Soldier System – Enhanced System. The core of IdZ-ES merges power supply and command-and-control functions in a smartphone-style electronic backpack. The advanced version encompasses an expanded array of capabilities, including a second radio for communication with higher-echelon commands. There’s also a low-weight version for special operations forces.

Singapore Technologies Engineering’s Ariele future soldier suit features an augmented reality display in a helmet which also provides protection from shrapnel, facial recognition for identifying “persons of interest,” body armour which can regulate temperature, an exoskeleton to convert kinetic energy from walking or running into usable electrical power, a vest-mounted camera, and smart watches to track vital signs.

Originally published in Issue 2, 2018 of MS&T.