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Expect our morning routines to become more automated in the future. Stepping out of bed will trigger the lights to turn on and the blinds to open. When you walk into the kitchen, your house will greet you and start making coffee.  Your fridge will feel you approaching and pour you a glass of orange juice.

For the automatic house to work, reliable and inexpensive motion sensors are needed to track a person’s movements. Researchers from the University of Glasgow have developed a way to turn radio and sound waves from basic technology into motion sensors.

The so-called ‘Bat-sense’ works similarly to how bats use echolocation to hunt. It generates real-time 3D images by tracking echoes as they reflect off surrounding objects. Batman has a similar device where he creates a sonar using the radio waves emitted by cell phones.

“Fundamentally, it’s the same thing as in Batman,” says Dr Alex Turpin, one of the lead researchers on the project. “We have more restrictions in our technology but the operational principle is the same.”

Unlike Batman, Turpin’s technology can only create images from a room that it has ‘seen’ before. It means that people cannot just have their own personal sonar hooked up to their cell phones. What it is useful for is tracking new movements in a room for security, safety, or even automation. It is also cheap and can be integrated with antennas or microphones – which are basically everywhere. In situations where a camera might be useful, this sensor can take its place.

‘Seeing’ like bats do

The automated home is some years out. So, in a way, Bat-sense is ahead of its time. However, it relies on simple principles taken from bats to work. Bats are blind and therefore ‘see’ by emitting sounds and tracking the echoes. Humans would also be able to do this, except that our ears saturate reverberated sounds.

“Otherwise, you would hear everything, all the time, and go completely nuts,” explains Turpin.

The Bat-sense is similar. It uses machine learning algorithm to read how fast radio or sound waves bounce between surfaces. An image is then generated which shows the room it has learned and any forms moving inside it. The resolution is not super detailed but can show whether someone is standing up, walking around, or lying down.

Stops burglars from coming in and keeps grandpa safe

CCTV cameras are becoming more popular in the Netherlands. While they are not illegal to use in the protection of one’s home, certain rules for privacy need to be followed. In order to get a high-resolution image – usually of someone’s face – cameras are needed.

“We don’t like it, but that’s what cameras are for,” says Turpin.

But if your goal was simply to track an unwanted person entering a room, then there is no need to film that. The Bat-sense monitors a room without giving up one’s privacy. It is also very secure. To scramble the device, intruders would need to know the exact frequency that is being emitted by the Bat-sense and have a device that emits the same. And this is assuming the room has no other ‘dummy’ frequencies that serve as decoys.

The problem here is that people do not mind having private cameras within their own homes. Turpin sees another application – monitoring the elderly and unwell.

“For instance, in a hospital room. If you could, you would put a camera in there,” says Turpin. “It would be useful to know if the patient is standing up, if they have moved, or if the patient fell down.”

What the Bat-sense brings is an ability to ensure patients stay safe without sacrificing privacy. It could be used in a hospital or an elderly home in case a resident fell down and had trouble getting up. It is also being further developed to become more sensitive. This would allow it to monitor the rise and fall of a patient’s chest – and alert staff of any irregularities.

A new way for Netflix to spy and the visually impaired to ‘see’

The best use for Bat-sense is still being sussed out: “It’s a technology looking for a problem,” explains Turpin. “We weren’t motivated by a problem with society, we were motivated by science and fundamental physics.”

As it is developed further, other ‘out-there’ ideas for the technology could come to life even more. For instance, currently it cannot be used to ‘spy’ on people. But all it needs is an antenna with a radio frequency to work, so, theoretically, it could be used by external parties to monitor others.

“I’m sure that Netflix would love to know how many people are sitting on one sofa,” jokes Turpin. “Then they can tell not only what you like but what your family likes to watch together.”

But Turpin does not think this is realistically possible. What he does see is a way to give humans and robots a new way to navigate the world. By combining multiple sensors – one on a person’s head and two on the shoulders – a person could ‘sense’ their surroundings. In the same way that bats ‘see’ with echoes, humans may well be able to the same way in the future.

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