[CompelTechnic]

I like that design idea for the rotating disc. It makes me wonder the best way to stress the material while on the "compressed side."

1. Make the edge of the disc rub against a low friction, spring-loaded compressing element (similar to commutator brushes, but designed to really transfer a large load). This is probably infeasible because friction would eat more energy than your cycle would move.

2. Have electric actuators that are mounted on the disk itself. These would have to be powered by slip rings via the shaft. These would be active for half of the cycle and inactive for the other half. Not sure whether they should be radial, azimuthal, or axial mounted. Seems kludgey.

3. Have the disk pass through a magnetic field, exploiting the magnetic effects the article mentions. I have no idea of any of the implementation details of this, but it sounds like a better idea than 1 or 2...