At work we use inductive coupling to power several dozen wireless
vehicles. These aren't small, as some are moving theaters that
carry 120 people, and our newest installation is a small fleet of
electric submarines.
Frankly, I'm a bit disappointed that MIT hasn't done better
research in the field than this article suggests.
Do your setups get a better than 50% transfer efficiency across
several meters
distance?
I don't have data on the efficiency. Distance is a few centimeters,
maximum.
I think the geometry is key: a short distance to a large vehicle
(pancake geometry) is going to be much better coupled than a long
distance to a small device (spaghetti geometry). (add to that the
fact that vehicles with a metallic body provide their own shielding,
increasing the coupling)
-Dave