A few months ago, we brought you the "You Built What?!" feature about Charles Guan's Electric Death Trap Shopping Cart Contraption. More recently, he released an excellent Instructable about making your own miniature electric hub motor.
A hub motor provides a space-efficient way to apply motive power to wheels -- especially wheels that were not necessarily designed to be driven, as Charles points out in the Instructable. The choice of an electric hub motor is going to be simpler and more efficient than hydraulic hub motors, which are frequently used on large construction, industrial, and agricultural equipment.
"That is, they're great EV hacking and conversion. They're compact and modular, require no support of rotating axles from the parent vehicle, and can be designed around the vehicle to be propelled. Pure DC electric hub motors, in fact, were used in some of the first electric (and hybrid electric) cars."
Cruise on over to the Instructable for the background and the important concepts needed to build your own.
"Hub motor electromagnetic fields are supplied to the stationary windings of the motor. The outer part of the motor follows, or tries to follow, those fields, turning the wheel to which it is attached. Energy is transferred to a brushed motor through physical contact of brushes to the rotating shaft of the motor. Energy is transferred to a brushless motor electronically, requiring no physical contact between stationary and moving parts."
Can anyone say that this can be done at home by oneself? I would say that this looks a little more complicated and above my possibilities.
It's just an induction motor. Once you understand the theory, they're pretty simple.