Charles River Analytics Inc. has received funding from the US Army Research Institute for the Behavioral and Social Sciences to build its Physiological Index of Situation Awareness (PISA) system with SA Technologies. The unobtrusive, multimodal, and real-time PISA system monitors soldiers’ evolving situational awareness (SA) and determines when lapses in SA occur.


The US Army Research Institute for the Behavioral and Social Sciences is interested in the scientific investigation and assessment of situation awareness in complex operational environments. Charles River Analytics is researching sensors that could be attached to soldiers, gear, or vehicles to enhance missions. PISA uses multiple wearable sensors that monitor physiological and neurophysiological signals from soldiers and make predictions about their level of situation awareness in real time. Photo Credit: US Army illustration.

Soldiers must operate in increasingly complex and chaotic battlespaces, partially due to unreliable intelligence, such as a false message from an adversary or information denied environments.

“To perform their jobs and fight effectively, soldiers must develop the necessary skills to attain and maintain SA for their assigned tasks,” said Dr. Bethany Bracken, Principal Scientist at Charles River Analytics and Principal Investigator on the PISA effort. “PISA includes breakthrough wearables sensors that decode the physiological correlates of soldier’s evolving SA in real time, making it easier for commanders to intervene during a training simulation to tailor trainings to be optimally effective.”

PISA uses a sensor suite, including fNIRS Explorer (left) or fNIRS Pioneer (middle, right), to gather data related to cognitive workload and SA. Image credit: Charles River Analytics

Charles River’s PISA system includes a minimally invasive multimodal sensor suite, including functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG), eye tracking, and cardiac sensors. PISA uses Sherlock, its open and extensible software and hardware platform, to process and fuse this sensor data and derive informative variables related to SA in real time. Then, Charles River leverages its probabilistic modeling and machine learning expertise to estimate soldiers’ cognitive state, such as SA.