3 ms·

It might have to do with the fact that he's using rubber bands to turn the arm, while historical trebuchets used weights. A weight is limited in how fast it can

It might have to do with the fact that he's using rubber bands to turn the arm, while historical trebuchets used weights. A weight is limited in how fast it can accelerate so you need to use a lever (the arm) to increase the speed.

krasin 5y ago
Springs could be used instead of rubber bands. While "coil spring" is a relatively modern invention, other kinds of springs are known from the Bronze Age, accoding to https://www.designingbuildings.co.uk/wiki/History_of_the_Spring#Bronze_Age https://www.designingbuildings.co.uk/wiki/History_of_the_Spr...
- Retric 5y ago
  Springs are much older than that, the bow is perhaps the most famous example from antiquity.
  - krasin 5y ago
    Good point. I somehow was thinking about metal springs (Romans used springs from lead, for instance), but there's no reason to restrict it to metal.
    - throwanem 5y ago
      Lead springs? They'd have to be absurdly oversized by modern standards to hold up to any kind of force without deforming, I'd imagine. I'd love to read more about them, if you happen to have a cite handy.
      - TheSpiceIsLife 5y ago
        I don’t reckon. Surely the above comment is confused, misremembering leaf spring as lead spring. Leaf springs appeared as early as the Roman empire as a form of primitive suspension for chariots and other two-wheelers. Instead of steel, savvy Romans used flexible wooden sticks. https://connect2local.com/l/112910/c/478618/examining-the-fascinating-history-of-the-leaf-spring https://connect2local.com/l/112910/c/478618/examining-the-fa...
        throwanem 5y ago
        Ah, yeah, that makes a lot more sense.
        krasin 5y ago
        Thank you. This is exactly the mistake I made. It raised some flags in my head when I read it, but then again - Romans did so many things out of lead that I did not challenge it.
  - deleted 5y ago
    [deleted]
  - jacquesm 5y ago
    And they can be quite formidable, a full size wooden (yew, maple, ash) bow takes a lot of arm strength to properly pull. Just a few shots and you'll be wishing for stronger muscles.
    - pbhjpbhj 5y ago
      You can double the muscle power available by using a foot-bow.
- deleted 5y ago
  [deleted]
- mcguire 5y ago
  Torsion springs are another option. https://en.wikipedia.org/wiki/Torsion_siege_engine https://en.wikipedia.org/wiki/Torsion_siege_engine
eeperson 5y ago
You could use a weight combined with pulleys or gears to get a faster acceleration.

krasin 5y ago

Springs could be used instead of rubber bands. While "coil spring" is a relatively modern invention, other kinds of springs are known from the Bronze Age, accoding to https://www.designingbuildings.co.uk/wiki/History_of_the_Spring#Bronze_Age https://www.designingbuildings.co.uk/wiki/History_of_the_Spr...

Retric 5y ago
Springs are much older than that, the bow is perhaps the most famous example from antiquity.
- krasin 5y ago
  Good point. I somehow was thinking about metal springs (Romans used springs from lead, for instance), but there's no reason to restrict it to metal.
  - throwanem 5y ago
    Lead springs? They'd have to be absurdly oversized by modern standards to hold up to any kind of force without deforming, I'd imagine. I'd love to read more about them, if you happen to have a cite handy.
    - TheSpiceIsLife 5y ago
      I don’t reckon. Surely the above comment is confused, misremembering leaf spring as lead spring. Leaf springs appeared as early as the Roman empire as a form of primitive suspension for chariots and other two-wheelers. Instead of steel, savvy Romans used flexible wooden sticks. https://connect2local.com/l/112910/c/478618/examining-the-fascinating-history-of-the-leaf-spring https://connect2local.com/l/112910/c/478618/examining-the-fa...
      - throwanem 5y ago
        Ah, yeah, that makes a lot more sense.
      - krasin 5y ago
        Thank you. This is exactly the mistake I made. It raised some flags in my head when I read it, but then again - Romans did so many things out of lead that I did not challenge it.
- deleted 5y ago
  [deleted]
- jacquesm 5y ago
  And they can be quite formidable, a full size wooden (yew, maple, ash) bow takes a lot of arm strength to properly pull. Just a few shots and you'll be wishing for stronger muscles.
  - pbhjpbhj 5y ago
    You can double the muscle power available by using a foot-bow.
deleted 5y ago
[deleted]
mcguire 5y ago
Torsion springs are another option. https://en.wikipedia.org/wiki/Torsion_siege_engine https://en.wikipedia.org/wiki/Torsion_siege_engine

eeperson 5y ago

You could use a weight combined with pulleys or gears to get a faster acceleration.