The problem with your calculations is that, though linear speed would decrease as one moved towards the center of the ring, the angular velocity would be the same, and the centripital force (M * V^2 / R) would increase as the person moved towards the center of the disc. So using any sort of rotating mechanism would be quite difficult.
Slashdot Mirror
The problem with your calculations is that, though linear speed would decrease as one moved towards the center of the ring, the angular velocity would be the same, and the centripital force (M * V^2 / R) would increase as the person moved towards the center of the disc. So using any sort of rotating mechanism would be quite difficult.