Stephanie Brown on sensors worn by soldiers for their vital data

Another in a series of previews for Sensors Converge 2023 featuring Stephanie Brown, enhanced soldier program manager for the U.S. Army.

Q: You are an important speaker, part of a full day workshop at Sensors Converge 2023 on June 20 about printed, flexible, stretchable and functional e-fabric sensors and systems behind them.  Can you describe one or two technologies that might be advantageous to the US military?

Brown: I lead a portfolio of research that focuses on the Army’s persistent and challenging problem of enhancing the Soldier and Small Unit’s ability to understand and make accurate and decisive decisions during combat operations.  With that in mind, I’m interested mostly in the novel concepts that could change the way we sense the Soldier and the operating environment in the future. The Army has investments in novel e-textiles, flexible, printable and wearable sensors for human performance monitoring, equipment status tracking, observing the environment, and a variety of other applications. 

Some examples include a tooth implant flexible sensor that could provide biodata, allowing us to understand things like glucose and salt levels in real-time.  There is an epidermal printable membrane sensor in development that can achieve similar biomedical monitoring to include heart rate.  Other textile based flexible sensors could provide on-body information about a wide range of things, including sweat and hydration (which are hard to measure currently), head impact forces, environmental acoustics and light (which can queue equipment to shift modes or directionality providing augmented vision and situational awareness), or even embedded communications.  The possibilities are endless!  I think sensors utilizing form factors that allow for employment in ways we current can not achieve are extremely exciting and could solve some of our challenges on the battlefield.

Q: What are the goals of these technologies?

Brown: The Army needs technology to sense everything about the battlefield, including the soldiers themselves, in real-time.  In parallel to sensing, we need to develop AI/ML algorithms to help understand the data being sensed.  In combination, our Soldiers and Commanders will be able to fully understand both our adversaries and ourselves, as well as the environment in which we engage.  In general, this may allow us to reduce risk and injury to our Soldiers and protect our people.  For example, some of the wearable sensors could provide health monitoring and casualty care, to include triage information to assist medics with injury identification, classification, and treatment. 

Q: What obstacles did you or other teams need to overcome?

Brown: I think this field is ever-evolving.  One challenge that is uniquely military that must be considered is how these sensors look to observers, in other words do they have a signature or footprint that could make our Soldiers more vulnerable to detection.  Passive sensors are generally less detectable.

Another challenge is sensor form factor and signal noise.  Currently, wearable physiological monitors are very popular in the commercial fitness market. The Army tries to leverage not only the innovation of industry, but also the marketing that drives acceptability of these products across our end users, the Soldiers.  We find that if we allow the Soldiers to wear their personal fitness devices and leverage the data for our own health and performance monitoring purposes, then we get much higher wear compliance and better quality data.  If we provide a military specific sensor to achieve the same goal, we fall woefully short of the mark.  In addition, the form factor can drive the amount of noise, or signal interference and variability, in the data.  For example, e-textiles intended to derive signal from bodily fluids like sweat, saliva, and tears, have constantly changing background noise.  This noise can be environmental, mechanical, electrical, chemical, etc., and in many cases are unique to the military context.

Yet another challenge is durability for continuous use.  Our Soldiers push their equipment to the extreme limits in very harsh environments.   With e-textiles and flexible sensors, there is a potential durability challenge.  If these sensors are employed on body via uniform parts, they need to be long lasting, washable, and comfortable to stand up to the Soldier tests!  However, many of our current biomarker sensing capabilities have reuse challenges requiring research and development to improve chemical stabilization (e.g., aptamers, enzymes) for use in rewearable e-textiles.  Many of our current prototypes are single use or limited repeated use, degrade over time, or need to be reset or recalibrated, which is not ideal for a Soldier-issued uniform part.  Additionally, battery life is a major consideration.  Reducing energy requirements and recharge time is a must for military sustained operations use-cases.   

Q: Have you seen much benefit in having sensors themselves incorporate smart tech, even AI?  How would that be used?

Brown: The incorporation of AI in the future battlespace to help with the filtration and interpretation of the data will be critical, whether the sensor itself has an on-platform AI application prior to sending off the data for use, or if that process occurs in the cloud or at a central processing node.  The Army predicts that the future battlefield will be “transparent”, meaning there will be so many sensors (friend, foe, and civilian) that it will be hard to stay hidden.  However, we can utilize AI to leverage all of those sensors and volumes of data to our advantage by interpreting it at faster than human speeds.  

Stephanie Brown is the Enhanced Soldier Program Manager for the U.S. Army Combat Capabilities Development Command Soldier Center. Her background includes an M.S. in Human Systems Integration and a B.S. in Design and Environmental Analysis. She has spent 19 years working in the military.She joins a full day workshop featuring 10 speakers at Sensors Converge 2023, “Printed, Flexible, Stretchable and Functional E-Fabric Sensors and Sensor-based Systems,” which begins at 9 a.m. PT June 20. Register online to attend!