Fitbit for the face can turn any face mask into a real-time health monitor
Evanston, Illinois – A team of Northwestern University engineers says a smart, quarter-sized sensor can turn an ordinary face covering into a comprehensive health monitor. Their invention, which they call a “Face Fitbit,” uses magnets to attach any surgical cloth face mask that N95 people wear all day.
FaceBit allows a person to track breathing rate, heart rate and even when to wear a mask through a smartphone app that receives wireless signals from the chip. The study authors say FaceBit can alert users to potential problems in real time, such as a high heart rate or other breathing problems. Moreover, the sensor can detect problems with the user’s face mask, such as a poor fit or air leakage somewhere in the cap.
FaceBit works with the warmth of your breath!
Engineers say their devices harvest power from an unlikely source – the user! Besides the small battery, the chip draws power from surrounding sources such as the wearer’s movements and even the heat of their breath. This eliminates the need to charge FaceBit and keeps the battery fresh for longer.
“We wanted to design a smart face mask for healthcare professionals that didn’t need to be plugged in inconveniently during the shift,” says Josiah Hester of Northwestern University, who led development of the device, in a university edition. “We’ve boosted battery power by pooling energy from different sources, which means you can wear the mask for a week or two without having to charge or replace the battery.”
Tests on FaceBit have found that it performs as accurately as clinical grade devices and can last more than 11 days before needing a recharge.
The device knows if your mask does not fit properly
Hester’s team began their research for this project by interviewing doctors and nurses who constantly had to wear an appropriate face mask. Healthcare professionals must regularly undergo a 20-minute “fitness test” to ensure that N95 masks provide a proper seal on their faces.
These tests use cumbersome machines that pump an aerosol mist that allows the wearer to check for leaks. Although FaceBit cannot replace these tests, it is able to warn users if the mask does not fit tightly by sending an alert to their phone.
“If you wear a mask for 12 hours or more, sometimes your face can become numb,” Hester says. “You may not even realize that your mask is loose because you can’t feel it or you are too exhausted to notice. We can approximate the process of testing the fit by measuring the resistance of the mask. If we see a sudden drop in resistance, it indicates a leak, and we can alert the wearer. “.
Precise movements reveal your heart rate
As for the real-time health data that FaceBit can track, the researchers say the device can sense the exact movements everyone makes while breathing. The team notes that every time a person’s heart beats, their head moves by an almost unrecognizable amount. The smart chip uses this movement to calculate your heart rate.
“Your heart pushes a lot of blood through the body, and the ballistic force is very strong,” Hester explains. “We were able to feel this force as the blood travels through a major artery to the face.”
FaceBit also knows that stressful events can make people breathe hard. When it detects signs of rapid breathing, the device can use the information to alert the wearer that it may be time to take a break and calm down.
Hester hopes the next version of FaceBit will be battery-free, using only the wearer’s body heat and the sun to power it. At the moment, FaceBit still needs to undergo clinical trials before it enters the market.
“FaceBit provides a first step toward practical facial sensing and heuristics, and provides a sustainable, convenient and convenient option for public health monitoring of workers on the front lines of COVID-19 and beyond,” Hester concludes. “I’m really excited to hand this over to the research community to see what they can do with it.”
FaceBit details are published in the magazine ACM’s actions on interactive, mobile, wearable and ubiquitous technologies.