[jutta]'s comment in the linked idea got me thinking. Her proposed rotating pipe would be "like a hamster wheel for skaters". However, imagine a skateboard pipe which rotated not on its long axis, but around a central point like a propeller mounted on the ground.
The advantage to this: imparting momentum to the skater. Imagine a stationary skater on her board just outside of the pipe center. The pipe's rotation would push her toward the end of the pipe and out. Skaters starting in the middle and moving out toward the ends would pick up speed as they moved out, then slow as they move back in.
The factor limiting skaters from performing an entire circuit of a closed pipe is the intermediate points: lost velocity at the 2 oclock position will cause the skater to fall through the air onto the floor of the pipe. The structure of a pipe, full or half, precludes the skater from gaining enough velocity to do a loop-de-loop.
The rotating skateboard pipe makes the loop-de-loop possible. And isn't that what we've all been waiting for?-- bungston, Aug 24 2007 The Peacepipe The_20PeacepipeInspiration! [bungston, Aug 24 2007] Pondering this one again. A problem is pipe entry. One could drop into the middle but that is somewhat cumbersome to do over and over. Plus skaters would tend to rocket out of the end of the pipe which is fine but also ends the pipe experience. So instead of a straight pipe rotating like a propellor, the pipe curves around and meets itself making a full circle. It rotates with the axis on the circle, rather than the perimeter. On moving away from the axis the skater will accellerate. It will be more work to get back to the axis through the other half of the big circle but the return trip will be just like regular skating, up an incline.-- bungston, Jan 05 2011 // It rotates with the axis on the circle, rather than the perimeter.// Don't you mean "rather than the centre"?
How about a figure-8-shaped pipe, spinning in the horizontal plane with the axis at the central intersection?
The intersection itself could be a true crossover, or the crossing pipes could be on different levels.-- MaxwellBuchanan, Jan 06 2011 random, halfbakery