The wheels on my Roomba 760 got to worn down, the machine had trouble getting around on rough terrain, like carpet to wood floor transitions.

I decided to sacrifice one of them to figure out the tire profile, and then design a new set to print in NinjaFlex.

UPDATE: I was pleased by the result, on flat bare floor and carpets. But the filament I used was not NinjaFlex, must have been semiflex or something less rubbery, because the wheel did not grip enough to have the robot climb a simple doorframe, it simply got stuck. I then ordered some real NinjaFlex, and redesigned the wheel to have straight tracks and made it wider. The result is so much better, doorframes are no longer an issue.