Essentially cheap, battery-less, sticker-type devices, RFID tags transmit a signal when temporarily powered up by the electromagnetic signal from a reader device. Now, thanks to experimental new technology, they could be used to bring "smart" functionality to plain ol' analog objects.

Usually, RFID (radio frequency identification) tags are simply used to provide basic information. In a typical scenario, a worker might point a handheld reader at a tag that's applied to an object which is being shipped, or that's sitting on a warehouse shelf. The tag would respond by transmitting a signal, containing uniquely-coded information such as the serial number or ship date of the item.

The IDAct system, however, takes things a step further. Developed by a team at the University of Michigan, it can detect tiny fluctuations within a tag's signal, indicating whether or not the tagged item is in motion, or if it's being touched. Additionally, by analyzing changes in a room's electromagnetic field, the system can determine if a person is present within that room.

"Every object causes electromagnetic interference in a specific way," says Assoc. Prof. Alanson Sample. "We can use that information, along with information from RFID tags, to get a very detailed picture of what's going on in a given space."

In a test that was recently conducted in an apartment, the system collected 26 hours worth of data from a variety of tagged items. It proved to be over 96 percent accurate at detecting specific activities.

Once developed further, the technology could conceivably be used to track any number of actions. These could include the drinking of water from a glass (ensuring adequate hydration), the taking of medication from a pill bottle, or even the regular preparation of meals in seniors' kitchens. And while the system currently uses a machine learning algorithm on a laptop to process the data, plans call for more conventional RFID readers to ultimately do the thinking – a series of them could be set up in users' homes.

The scientists are now looking for partners to help commercialize IDAct, which may initially find use in elder care settings.