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Rope ascension using stored spring energy

  1. Dec 8, 2011 #1
    Just looked at a video of the atlas rope ascender (google it) and thought it was pretty cool. However, I feel as though using a more "capacitive" approach and taking advantage of the fact that ascensions would not occur frequently could allow for the use of a system that slowly recharges over time, either using capacitors or stored mechanical energy (springs). Unless I am missing something, I imagine capacitors would require large DC motors still. Going to a small, light system, are there any torsion springs that can store large amounts of continuous energy, possibly put some in series or parallel. Essentially, like a huge watch spring able to output ~500-1500 watts for a few seconds.

    Some target specs:
    350 lbs at 5 ft/s ~ 300 watts, but this seems questionably low to me. If this is right, at 50% efficiency, I imagine 600 watts would be an absolute minimum.

    Shooting for 50 feet, 10 seconds * 300 watts = 3 kJ of energy. Is this even ballpark feasible?
  2. jcsd
  3. Dec 10, 2011 #2

    Your power conversion is incorrect:

    1 HP = 550 ft*lbf/s
    1 HP = 746 watts

    350 lbf at 5 ft/s
    = 1750 ft*lbf/s
    = 3.18 HP
    = 2370 watts
  4. Dec 10, 2011 #3
    yeah, that did seam really low, and I did it really quickly. After doing a little more research, it really just doesn't seem that feasible.
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