This AI can see people through walls. Here's how.

Radio signals coupled with artificial intelligence have allowed researchers to do something fascinating: see skeleton-like representations of people moving on the other side of a wall. And while it sounds like the kind of technology a SWAT team would love to have before kicking through a door, it's already been used in a surprising way--to monitor the movements of Parkinson's patients in their homes. Interest in this type of technology dates back decades, says Dina Katabi, the senior researcher on the project and a professor of electrical engineering and computer science at MIT. "There was a big project by DARPA to try to detect people through walls and use wireless signals," she says. But before this most recent research, the best these systems could do was reveal a "blob" shape of a person behind a wall. The technology is now capable of revealing something more precise: it depicts the people in the scene as skeleton-like stick figures, and can show them moving in real time as they do normal activities, like walk or sit down. It focuses on key points of the body, including joints like elbows, hips, and feet.