One year ago my friend asked me to work on the electronics and mechanics of his lock whose design and casing had been made by a designer friend of him.
I made a proof of concept with the guts of a rc toy, a battery laying around and a small reduction gear .
the lock itself was CNC-Machined out of plexiglass scrap, a few bits of unknown gray plastic, and small chucks of aluminium.
there is a worm gear from a dvd drive that moves a centre piece which pushes locks against the cable.
CNC route for plexiglass milling of the locking mechanism (2 sides of a small enclosure)
Electronics proof of concept. the atmega328 and the bluetooth RS232 TTL HC-05 module are small enough to fit into the metal case. they were controlled in a first place by Ardudroid by Techbitar to enable pin13 to which is attached the motor driver.