Saturday, January 07, 2006

Through wall motion detector

The DARPA (US Defense Advanced Research Projects Agency) Special Projects Office has announced Radar Scope, a nifty gadget that acts like a 'stud finder' for motion on the other side of a wall. The DARPA prototype apparently can 'see' through 12 inches (30.5 cm) of concrete and then an additional fifty feet (15.24 meters) into a room. The article also says that it is sensitive enough to detect even the motion of breathing. The latter claim is particularly impressive. I'm curious to know whether it is detecting some change in the person's chest cavity or getting a reflection off of dog tags or some other body-worn or -carried article.

Even though DARPA is best known for its cutting-edge research, this technology is believed to be mature enough that their plan is to field it in Iraq at the squad level this coming spring. From the picture, the device housing looks field-ready and the typical gotcha for many advanced electronic technologies in the field (namely, the power source) looks to be a non-problem since it runs off of AA batteries.

This capability seems like it could be a nice complement to the existing ways of checking a room remotely - polecams (camera on a pole held up to the window), climbing robots, and contact mics (or accelerometers).

The article goes on to say that proposals for a follow-on technology program called Visi Building are being taken. The aim for this program is to go from motion detection to actual through-wall imaging - a much harder task.

Hat tip to Engadget.


Keith said...

The Drudge Report linked to this story but had a tag line of hearing through walls.

a.a said...

Really interesting. Wonder how they do this. There isn't any detail on the actual technology behind it, but I guess that is to be expected.

You are right about the AA batteries.. that is a big plus (or minus sometimes).

Keith said...

I've looked into how one would implement this type of capability in the past and, in principle, it is fairly straight-forward. You would have to range gate the reflections and then do some form of change detection. Of course, movement of the imager itself has to be ignored during the change detection process.