Researchers at Western Michigan University have unveiled a wearable capacitive pressure sensor designed to improve the fit of athletes' helmets — and, hopefully, reduce the risk of traumatic brain injuries (TBIs).
"A novel porous polydimethylsiloxane (PDMS)-based capacitive pressure sensor was fabricated by optimizing the dielectric layer porosity for wide-range pressure sensing applications in the sports field," the researchers, led by first author Simin Masihi, write in the abstract to their paper.
"The porous PDMS dielectric layer was fabricated by introducing nitric acid (HNO₃) into a mixture of PDMS and sodium hydrogen bicarbonate (NaHCO₃) to facilitate the liberation of carbon dioxide (CO₂) gas, which induces the creation of porous microstructures within the PDMS dielectric layer."
Using this the team developed nine different pressure sensors, then placed 16 of these sensors on a wearable cloth cap designed to fit underneath an off-the-shelf football helmet. Data from the sensors proved the concept: Higher pressures were recorded in those with bigger heads, providing data which could be used to offer the ability either select the best off-the-shelf helmet from a selection of sizes or even to customize a helmet for the perfect fit.
"According to the U.S. Centers for Disease Control and Prevention," notes the American Chemical Society of the research, "1.6 to 3.8 million sports- and recreation-related TBIs occur each year in the U.S. Field data suggest that loose or improperly fitted helmets can contribute to TBIs, but no devices currently exist that can provide information about how well a helmet conforms to an individual player's head."
The team's work has been published in the journal ACS Sensors under closed-access terms.