Fallen And Can’t Get Up? These New Sensors Have Already Sounded The Alarm

Instead of a button to press, what if the entire house could sense when someone had an accident?

In the early 1990s, the medical alarm company LifeCall ran commercials that immortalized the phrase: “I’ve fallen and I can’t get up!” (with a little help from Steve Urkel).


But the fact is that these alarm pendants and other devices that the elderly wear to alert the outside world when they’ve taken a spill aren’t always effective. One in three elderly people over the age of 65 falls each year, and some seriously injure themselves–falls are the leading cause of hospital admissions for trauma in this age group. What’s more, 80% of elderly adults who own call buttons didn’t use the device when they had a serious fall, according to a 2008 study. Most weren’t wearing them at the time.

Now researchers at the University of Utah are developing a sensor network for the home that could automatically detect a fall and notify a caretaker. “We wanted to have it so a person doesn’t have to wear a device,” says Brad Mager, the electrical engineering student who worked on the project.

Mager’s working prototype system is an array of 2.4 gigahertz radio frequency sensors (similar to home wireless networks) installed in a room at standing level and near the floor. Analyzing disturbances in the radio signals the sensors transmit–especially how fast they change–can determine whether someone has fallen, as opposed to say, just calmly lying on the floor. The analysis the researchers developed can also estimate the severity of a possible fall.

Read more about aging in place and the city as the new senior center.

The next step for Mager and his advisor, assistant professor Neal Patwari, is to commercialize the sensors into a relatively affordable product that could be installed in a home or in an assisted living facility. Patwari’s startup, Xandem Technology, already sells a similar product that detects home intrusions with better accuracy than infrared sensors. For detecting falls, they will have to test the system in real home environments–where clutter, other people, or maybe even pets could get in the way. The goal is to reduce the cost and false detections.

Mager–who presented his work at a conference in London this week–speaks about the work in the light of the exploding population of elderly people. In just a few years, the World Health Organization says the number of adults worldwide over age 65 will outnumber the number of children under five for the first time.

“Context-aware” home automation technologies are starting to make it easier for elderly people to “age in place” for longer and could reduce pressure for 24-hour home care. Mager’s radio tomography sensor system could also, say, be used to monitor and analyze more of an elderly adult’s activities at home, so a remote caretaker might notice signs of mental decline even without being there all the time.


Assisted living facilities, Mager imagines, could be built with these systems already installed. “The idea is that elderly people will be able to live at home and be independent longer than they can now,” he says.

About the author

Jessica Leber is a staff editor and writer for Fast Company's Co.Exist. Previously, she was a business reporter for MIT’s Technology Review and an environmental reporter at ClimateWire.