I will admit that "no problemo" made it sound easier than it actually is. But in the past I considered it literally impossible whereas these days I'm confident it is possible, using well known techniques.

> There isn't a data bank of millions of images of cut / uncut grass

True - but in my case I literally already had a robot lawnmower equipped with a camera. I could have captured a hundred thousand images pretty quickly if I'd known it was worth the effort.

> With something like a lawnmower, you don't want it to kill people or run over flowerbeds.

I agree - at the time I was actually exploring a hybrid approach which would have used landmarks for navigation when close enough to detect the landmarks precisely, and cut/uncut boundary detection for operating in the middle of large expanses of grass, where the landmarks are all distant. And a map for things like flowerbeds, and a LIDAR for obstacle tracking and safety.

So the scope of what I was aiming for was literally cut/uncut grass detection, not safety-of-life human detection :)