Digital Desk, San Francisco. The new Echo and Echo Dot speakers can now use ultrasound to detect engagement in your home and turn on and off other connected devices such as lights or fire TVs. First recorded at Amazon’s Fall Hardware event in September, The Verge reports, Echo and Echo Dot fourth-generation speakers can now detect inaudible ultrasound waves to find out if there are people in the room.
You can enable or disable this feature in the Alexa app, where you can also set up occupancy routines to use this new capability, such as turning on the lights when you enter the room and turning it off when you leave the room.
You can also have an Alexa Play music or radio station when you see motion near the Echo device during the allotted time and then you can turn off the tune after leaving. The function under Motion Detection is listed in the Alexa application settings for each compatible Echo device, and here you can turn the capability on or off.
Echo speakers do not have a camera, so instead, the device detects motion by reflecting an inaudible ultrasound wave that reflects nearby objects before returning to the device’s microphone.