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For the moment it just decapitates everything smaller than 2 inches and leaves the tall stuff alone so obviously the first days of growth you'll still need to weed manually, but for the rest it should leave it alone.
This is the first prototype, I am very sure that in a few years this will get a camera and will do pattern recognition so you can program it to kill everything that's not crop.
Think Skynet for weeds, that's how it will start muahaha!

I did see this thing come up in my FB feed a few days ago. Haha. Still think it's weird. But I think the vacuum things are weird too. Hahah