LONDON: Google’s new Pixel 4 represents the first time that radar has appeared on any mobile phone. On the Pixel 4, it powers a motion sensor that Google uses to drive a suite of features, including gestures to control the device hands-free, and faster face unlock (but there’s a big caveat here). Google aptly calls the sensor Motion Sense.
Phone-makers have experimented with motion control for years, using the camera sensor to know where you are and interpret what it is you want to do hands-free, like swipe through photos in a gallery and switch tracks in a music app. Some, like the LG G8, have even concocted elaborate motions to launch certain apps by pinching your fingers into a bird’s beak, or adjust audio by miming a turn of a dial.
Before we get into anything else, know that radar isn’t the same as face unlock. Google Motion Sense understands when you’re reaching for the Pixel 4 and lights up the screen, bracing for your face to come into range and do the rest. But that’s all the radar-fueled chip inside does. The sensor, which Google calls Soli, isn’t actually scanning your mug to make sure you’re really you.
For that, Google relies on an infrared camera to project dots on your face, just like Apple uses in the iPhone for Face ID. We’re not sure how many dots are being projected onto your face (we asked), but it’s this depth map that does the actual unlocking. Motion Sense just speeds up the process so you don’t have to swipe to unlock the phone, or even pick it up to trigger raise-to-wake.