Amazon has switched on a clever new feature in its fourth-generation Echo and Echo Dot speakers, which enables these smart speakers to detect when someone has walked into the room. Echo can use this new sense to proactively switch on connected smart home gadgets, like lights or a Fire TV streaming sticks. The new feature, which is available now, was announced during Amazon’s blockbuster September launch event.
If you already own a fourth-generation Echo or Echo Dot (these are the ones first announced in September 2020 with a spherical design for improved sound), you’ll be able to enable or disable the new functionality within the Alexa app. This companion app is available on Android and iOS. If you switch on this extra sense, you’ll be able to use your movements around the house to trigger other actions from your smart home gadgets.
For example, you’ll be able to tell Alexa to switch on the smart bulbs in your lamps when you walk into the room. Or you could create an Alexa Routine – which daisy-chains a number of common commands together based on a single, customisable trigger word or action – that flips the switch on a few lights and tunes into your favourite radio station when you walk into the kitchen in the morning.
To enable the new trick, launch the Alexa app and head to the settings menu for each smart speaker listed in your Devices tab. The ability to detect presences can be found under the Motion Detection menu. A toggle can be used to enable or disable the feature.
While we’ve seen motion-sensing built into Echo Show devices, which arrives with a touchscreen display and camera built-in, we’ve never seen anything like this on the voice-only Echo line-up before. To sense a presence in the room, Amazon beams an ultrasound wave from the smart speaker. This is inaudible to human ears, so you don’t need to worry about an annoying screech from your clever AI-powered speaker.
The Echo and Echo Dot are capable of working out whether anyone has wandered into the room (or left) based on how the ultrasound wave bounces off objects in the room, before travelling back to the far-field microphone array used by the gadget to listen to your voice commands.
Google uses ultrasound with its Nest Hub smart home displays to change the size of the elements of the user interface, based on how close you’re standing to the small screen. For example, when setting a timer for cooking – the time remaining will expand to fill the entire display if you wander to the other side of the room, but will shrink down if you’re close to the screen.