If you're riding the wave of the quantified-self movement, you may not need to purchase a host of wristbands, bracelets, watches, cuffs and helmets that can track your health -- Google Glass can do the job just as well.
Researchers at the Affective Computing Group in the MIT Media Lab and Georgia Institute of Technology have found that Google Glass can correctly detect your pulse and respiration rhythms in real time. "It detects these physiological indicators with a very high accuracy when compared to FDA-approved sensors -- both pulse and respiration had only about one beat or breath per minute of error," says lead author and PhD student Javier Hernandez, speaking about this new research (PDF) for the first time to Wired.co.uk.
The big idea: the responses were measured using the built-in gyroscope, accelerometer and camera in Google Glass -- no external sensors needed. "The data from Google Glass is so much richer than a dedicated heart-rate sensor, because people use it in their regular lives," says Hernandez. The real-time physiological feedback could show you what calms you down, makes you afraid, or stresses you out as you go about daily life.
The MIT-Georgia Tech collaboration started off trying to attach external biosesensors to Google Glass, until Hernandez's team realised the in-built sensors could capture the same responses. The technology works by measuring subtle movements of your head. "Every time your breathe, or your heart beats, your body moves in a very subtle way, particularly your head where the Google Glass is mounted," says Hernandez. "The built-in sensors -- the accelerometer, gyroscope and camera -- can pick up these very, very slight movements while you're completely still, and we can extract the parameters we want, using signal processing algorithms."
The study
The teams recruited 12 Glass-wearing volunteers (an equal mix of men and women), who were asked to be still and breathe spontaneously for a minute in a range of positions: sitting, standing and lying flat. The same set of measurements was also taken after pedalling a stationary bike for one minute so the data reflected a post-exercise physiology.
Each sensor measures motion uniquely: the accelerometer tracks linear movement, the gyroscope maps head rotation and the camera measures movement of the scene you are looking at, in relation to your head.
The group found that the gyroscope was the most accurate sensor individually for both heart and respiration rates, achieving a mean absolute error of 0.83 beats per minute and 1.39 breaths per minute respectively; but a combination of all three sensors provided a similar level of performance. The advantage of the camera data (which was analysed by the Computational Perception Lab at Georgia Tech) is that the same algorithms could potentially detect the wearer's heart rate and respiration directly from Google Glass videos uploaded to YouTube, says Hernandez.
This latest research is part of a rise in wearables being used to track health and fitness. Conservative estimates by researchers show that the wearable electronics market, of which health/fitness trackers are about 61 percent, will represent at least $2 billion (£1.6 billion) in revenue worldwide by 2018. Apple endorsed the trend by releasing HealthKit, a health-tracking data platform and app as part of
ioses 8 in June, to pull in data from third-party health apps. Large institutions like hospitals are bringing big data to healthcare, by using simple wearable trackers and US employers are requiring employees to wear health trackers to determine health insurance premiums.
Real-life uses
But the ability to measure your physiology in real-time is not just useful for day-to-day fitness -- it can actually be life saving. "Resting heart rate is associated with cardiovascular disease, so you can determine heart health by detecting these parameters," Hernandez says. "You can start correlating those parameters with your daily life -- if you are having a very stressful time at work, you can see the changes in your data and use that information to change your behaviour or lifestyle."
Heart-attack patients are already using their wearable devices, including the Fitbit or Jawbone, to log a specific number of steps each day as part of their recovery regimes and the Glass indicators can provide accurate feedback of your recuperation. It could even be used as a stress measure. "Some of the most effective stress interventions make you breathe at a specific rate; your body relaxes at seven breaths per minute.
So it's a good way to keep tabs on your stress," Hernandez says.
The respiration indicator can also help to quantify sleeping problems like apnea, and the feedback can help you prevent them from becoming chronic problems. Next up: Hernandez wants to use Google Glass to detect the wearer's emotions. "It has a camera to provide context about who you are speaking to and where you are, which combined with physiological signs, can infer your emotional state," Hernandez says.
The next steps
Ultimately, the goal is to go beyond Google Glass. "The accelerometer, gyroscopes and camera, these are very standard sensors. You could potentially put them into regular glasses and extract the same parameters," Hernandez says. The technology (explained in the video in this story) will be made public at the
MobiHealth conference in Greece this November.
This article was originally published by WIRED UK
