Modern wearables like the Apple Watch use sensors like gyros and accelerometers to detect hand movements. Those components allow them to turn on their displays when you lift your wrist, as well as to ensure you’ve properly washed your hand. But thanks to the work of a joint team of researchers at Cornell Unversity and the University of Wisconsin-Madison, future wearables could offer more nuanced hand detection.
The team has developed a device they call the FingerTrak. The wearable employs four low-resolution thermal sensors, each the size of about a pea, to monitor the contours of the wrist. The cameras snap multiple images of the hand that a neural network then pieces together to create a 3D model of the hand.