You might assume tracking people’s location indoors would require a smart marker, be it a smartphone or something dedicated to the task, or alternatively a computer vision setup, but the Xetal wireless sensor system takes an entirely different approach, using an array of five infrared sensors to triangulate where a person or people are indoors. While the system needs at least two sensors to operate in a room—and normally four are used—in many cases sensors are not needed everywhere in a building, as one can infer locations indirectly from the lack of a person’s presence in another area.
As shown in the video below, this is extremely useful for care of the elderly or medical patients who shouldn’t walk unattended, allowing caregivers to intervene before a fall occurs. It’s actually been tested in around 100 care facilities, and the system is currently being tried out in different industries like bank security and school monitoring.
There’s also a wired version of this sensor array available, which is somewhat easier to set up as you only have to worry about two sensor packages and a base unit. A demonstration of how that version is mounted is seen in the video below: