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Climbing up a Rope

  (+13, -2)(+13, -2)
(+13, -2)
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Climbing up a Rope is usually quite an ordinary experience, but this rope has a variable spring at the top, meaning that with the right technique and timing, a rapid assent can be made.

Other than that, the experience is bound to be challenging, with the rope springing up and down as you ascend and descend.

xenzag, Jan 21 2012

Climbing Bear http://www.shopsmit...ymakerproj/mmp2.htm
[Vernon]s 2 rope version reminded me of this... [neutrinos_shadow, Jan 22 2012]

trampoline rope climbing similar idea [pashute, Jun 24 2013]


       Hmm. So, the idea is that you bounce up and down, but sort of ratchet yourself up overall?
MaxwellBuchanan, Jan 21 2012

       This should be tried with two such springy ropes adjacent to each other. And a large-ish weight at the bottom of each of both ropes. Set both ropes going up and down separately, but alternately. You start by grabbing one rope that is about to go up, while the other is about to come back down. You go up. Then you switch ropes as that one is about to go up and the one you are on is about to go back down....   

       Keep switching ropes til you reach your destination. The springs should be at the top, above your destination. Someone at the bottom may need to be present, to continue "pumping" the ropes, to provide the lift-energy that you will be using, going up by this method.
Vernon, Jan 21 2012

       [+] but there's something fishy about this...
FlyingToaster, Jan 21 2012

       If only this worked for bootstraps.   

       //a rapid assent// In this case, a rapid dissent, unless you can fasten the top in a way that doesn't inflict head trauma.
mouseposture, Jan 21 2012

       I see a new extreme sport in the making.
Alterother, Jan 21 2012

doctorremulac3, Jan 21 2012

       //but sort of ratchet yourself up overall// - you got it Max
xenzag, Jan 21 2012

       It makes me dizzy. +
blissmiss, Jan 22 2012

       shades of the Baron Munchhausen film, climbing down from the Moon, and finding their ropes too short to reach to the Earth, he lengthened them at the bottom with the bits he'd cut from the top..
not_morrison_rm, Jan 22 2012

       There is also the possibility of another variable spring at the bottom of the rope.
xenzag, Jan 22 2012

       This idea needs more explanation.
VJW, Jan 22 2012

       //This idea needs more explanation//
Canuck, Jan 22 2012

       I think it only works if the rope masses more than the climber.
MechE, Jan 22 2012

       The climber can be the mass, shirley?   

       When climbing up a rope using Prussick knots (which are sort of like ratchets that can only slide one way along the rope), I think I've use the natural elasticity of the rope in this way. (I hasten to add that this was long, long ago in galaxy far, far away, when my BMI was far, far lower.)
MaxwellBuchanan, Jan 22 2012

       This kind of reminds me of the guys who bungee jump using only ropes. They anchor the rope at a point lateral to the jump point, so a combination of the swing and rope elasticity keeps you from dying. It reminds me of that because if you miscalculate, it's generally your ass.
nomocrow, Jan 23 2012

       I'm trying to picture the motion, but picture what happens if you are stationary in the middle of the rope. You let your mass drop a bit to get it started oscillating. When it rebounds, it does so less than it stretched originally. If you release to grab higher, the rope is going to rebound further, leaving you gripping below where you started (somewhere between the start point and the initial drop. I think under no circumstances with a massless (or low mass) rope can you end up gripping higher than you started. If the rope masses at least as much or more than the climber, then it continues oscillating regardless of the climbers attachment state, so that would work.
MechE, Jan 23 2012

       If you're on a good length of bouncy climbing rope, you can fairly easily bounce enough to make the rope go slack. It takes a few bounces to build up enough oscillation, just like bouncing on a trampoline.   

       So, you could build up a decent bounce, and then pull in the slack (either by grabbing the rope, which would be difficult, or by pulling it quickly through a ratchety thing) to establish yourself at the higher point.   

       The problem is that you would then have to start the bounce all over again. The analog would be a large staircase made of trampolines, where your highest bounce just let you reach the next trampoline in the series.   

       Overall, you'll use at least as much energy as in a smooth ascent. But this would be more fun.
MaxwellBuchanan, Jan 23 2012

       That was my point. You won't lose much of the bouncing energy in a modern rope; you just keep adding to it with each bounce (supplying energy from muscular effort) - the rope acts as an (imperfect) accumulator.   

       But then when you capitalize on that bounce by ratcheting yourself up, that energy is used up, and you have to start over.
MaxwellBuchanan, Jan 23 2012

       If it's a strong, stiff spring with a heavy weight at the bottom you can pre-bounce the rope and ratchet up quickly. Alternatively it should be possible to use a really long spring at the top and bounce until you're bouncing near the top. Then just grab on there.
Voice, Jan 28 2012

       As a caver I can tell you that this is a horrible idea. I once saw some rock climbers using dynamic (stretchy) rope to bounce a pit. It took them forever to climb out, because the spring absorbed the effort that should have been applied to ascending the rope. This is why we use static (stiff with limited stretch) rope for caving. Even with static rope, long drops (over 150 feet) can take awhile to climb, partly because the rope absorbs much of your effort at the bottom.
dlapham, Jan 28 2012


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