That's from 2011. It works, but the resolution is low. As low-cost near-terahertz devices become available, useful devices for indoor robots should become available. Like this one:
Are the video lectures of this available somewhere?
I love living in the future! :-)
don't cook yourself with rf!
I'm kinda joking some radars generate enough rf even in the sidelobes (not where the radar is pointed, but on the ground) that the rf is calculated and the radar shuts off when the human threshold is exceeded. Done in realtime software (I had to maintain/update that code).