This has been blowing up in my news feeds and I thought I would share as I can see this being very useful in our domain.
Go read the article and watch the video.
The tl;dr is they embed ferromagnetic material into the plastic and then sense the backscatter WiFi signal that occurs as the 3D printed gears, springs, sliders, etc move.
I haven’t read the full paper yet so it isn’t clear to me how the data is decoded or how it would get into OH, but it sounds like a fantastic next step.