Mobile Knife Sharpeners

I see mobile knife sharpeners, generally outside of North America.  Like this man, most have ingenious, homemade mechanisms rigged up on bicycles or mopeds to both provide transportation and power the grinding wheels. I’m a bit envious because seems like nice life, riding around, getting exercise and grinding knives en plein air!  Looks like a nice acute bevel he is forming on the knife below.