Cross-Slide wrote:

I remember reading a book about motors, and one of the more interesting
ones was referred to as a "Printed Pole Motor" IIRC.

I believe they are now used in high-end machining centers as a way
to get very wide speed ranges at full HP without using gearing or
belt drives. I think they are also called switched reluctance
motors. They do not use any permanent magnets, but rewrite the
poles on an iron rotor.

Jon