A home security device from UK-based Cocoon claims to use sub-sonic sound detection coupled with machine learning to detect abnormal activity in a home and alert the owner.

Cocoon works by listening to sounds below the range of human hearing so that one device can monitor the whole home, according to the company. It works with a smartphone app, which it expects all occupants of the home and regular visitors to carry, because it uses the smartphone’s app to determine when legitimate people are at home or away.

Cocoon listens when the home is empty and for the first few minutes after somebody arrives home and uses its machine learning algorithms to decide what sounds are normal and what are not. So, for example, the family cat or dog would not trigger an alarm.

According to the company, “When you are away from home and Cocoon is armed, Cocoon regards the home as empty, and is listening and learning at all times … When you return home and Cocoon disarms automatically, your Cocoon will listen and learn for 15 minutes so that it gathers the same sounds generated when someone is entering your home.”

Cocoon can take up to 10 days to ‘learn’ the normal sub-sound profile of a household, the company says.

When it detects an abnormal sound Cocoon streams video to the cloud enabling it to be viewed on the app and alerts the smartphone users giving them the option to sound a siren built into the unit, call the police or a neighbour.

Cocoon is about to launch the product in New Zealand. A spokesman told IoT Hub: “We are waiting on confirmation for Noel Leeming and Harvey Norman NZ; we expect the products to be on the shelves mid-February.”

The company has no plans to make the product available in Australia. It may have trouble doing so because a local company, Cocoon Products produces home security products that are sold from time to time by Aldi. However, it can be bought online from several vendors on eBay for about $A380. The Cocoon website offers the product to only a limited number of countries. Amazon says it will not ship Cocoon to Australia.

Cocoon made a unit available for review to IoT Hub. One of the big claims made for it is that it can be set up in under a minute. We did not manage that, but setup was pretty easy. You do this by downloading the Cocoon smart phone app, entering your email address and the name and password of your WiFi network, which must be 2.4GHz.

You then communicate this information to the Cocoon acoustically by holding the phone near Cocoon, hit go and it chirps for a few seconds. It then takes a few minutes for Cocoon to connect to the Internet and update itself but once that is done you’re good to go.

You can arm and disarm Cocoon from the app, watch the video, and save up to three videos, and can trigger the siren, which is claimed to be an ear-piercing 90 decibels. We tried it and could not see how to stop it. However, it stopped of its own accord after about 30 seconds.

There have been several news stories about smart home devices that listen and send the sounds into the cloud. Cocoon assures that its device does not do this, saying: “Your Cocoon learns the sounds of your home to minimise false alarms. No data or analysis ever leaves your household, it all happens inside your Cocoon … Cocoon only pushes data to the cloud when there’s an alert or you stream live video. Everything else is stored locally in 30 second cycles, with old data continually burnt over. If there’s an alert the previous 20 seconds are also sent to the cloud to make sure you never miss a thing.

“If someone in your household live streams video then the LED light on your Cocoon will start flashing.”