E-Rope charges batteries as you jump it

I was never that great at jump rope in grade school. Our coach could do all these crazy jump rope tricks he used to try and make us do, just so we would get tangled up and fall I think. A new design concept called the E-Rope can charge batteries inside the rope as you jump, and you don't have to do any stunts.

It looks like a normal jump rope with fat handles. Inside those handles sit chargers for a quartet of AA batteries. As you jump, the rope spins some sort of charging mechanism that puts power back into the batteries.

The E-rope has a LED indicator on the side to show the charge state of the battery. After 20 minutes of jumping, the AA batteries will be fully charged.