Oddly, as much as Luna (my scardy-cat dog) is afraid of a lot of things, she's not at all afraid of powered wheelchairs, probably because she was exposed to my father and his powered wheelchair from an early age. I've noticed that she's actually more apt to go up to folks in wheelchairs than those not in wheelchairs, probably because she's learned that my father is also both a frequent snacker and a messy eater, so there's often accidental treats around him. :)