Amazon has flipped a switch and its latest Echo and Echo Dot smart speakers (the circular models) can use ultrasound to detect if people are in a room.
The purpose of this is to help turn off lights and connected devices when a person leaves a room without any input from the user. You can disable this feature from the Alexa app, but it will be on by default for most people. It’s located under the ‘Motion’ subheading in the app. Privacy-minded individuals may also want to know that this ultrasound system uses the microphones on the speaker to receive feedback.
Inside the app, you can also use this feature to set up routines to turn on lights or play music when someone enters/exits a room. This allows you to use an Echo in place of an actual Motion sensor, which should allow for less tech-clutter around your house. Amazon’s new Echo Show devices do this with a camera, so this now means that motion-sensing is a pretty standard Echo feature.
Google also uses ultrasound on its Mini and Nest Home smart display to detect when people are nearby. The Nest Mini will display volume controls, and the Nest hub displays will alter its interface to be more easily readable when people are standing far away.
However, Google doesn’t allow users to utilize this tech to set up routines like Amazon does.
Via: The Verge