Trajectory B/C

[AlphaTauri]

Well, from what I know, the catapult itself is pretty powerful (one of my teammates said when they pulled it all the way back and aimed it as high as it could go, they hit the gym ceiling, which is about 30 feet up) and it seems that it does take a fair amount of force to pull the pin. But when it's fired, the catapult doesn't move at all, most likely because it weighs a lot in the first place.

[starpug]

There you go, the weight of it creates a static friction greater then the force of the pull required to move the pin.

[Fireheart347]

Does anyone have a good idea on what to use for the launch mechanism for a catapult design? I was thinking door-hinges, but I am afraid they might have too much friction.

Gate latches are use alot, I don't know if that's what you are refering to.

Yes, that is what I meant.

[starpug]

Does anyone have a good idea on what to use for the launch mechanism for a catapult design? I was thinking door-hinges, but I am afraid they might have too much friction.

Gate latches are use alot, I don't know if that's what you are refering to.

Yes, that is what I meant.

Then, I do not think you have too much friction. Gate latches work great.

[jazzy009]

Okay...my team's kind of failing with standard stretchy rope stuff, anyone got a better idea?

a guy on my team wants to use a carbon fiber bar as an arm to supply the power...I've never even heard of carbon fiber, is it hard to get/has anyone tried this?
I'd rather not waste my time getting some exotic equipment if it's not worth it...

[AlphaTauri]

Okay...my team's kind of failing with standard stretchy rope stuff, anyone got a better idea?

a guy on my team wants to use a carbon fiber bar as an arm to supply the power...I've never even heard of carbon fiber, is it hard to get/has anyone tried this?
I'd rather not waste my time getting some exotic equipment if it's not worth it...

Uh, what exactly do you mean by "standard stretchy rope stuff"? But anyways, our team uses a combination of bungee cords and surgical tubing. (One is sort of optional, they use it to give the catapult more power if they need it.) And I've never heard of anyone using carbon fiber. We've always used wood and it seems to work fine...

[cypressfalls Robert]

is this what you are talking about http://www.robotmarketplace.com/marketp ... fiber.html

[Dark Sabre]

Okay...my team's kind of failing with standard stretchy rope stuff, anyone got a better idea?

a guy on my team wants to use a carbon fiber bar as an arm to supply the power...I've never even heard of carbon fiber, is it hard to get/has anyone tried this?
I'd rather not waste my time getting some exotic equipment if it's not worth it...

When Storm the Castle was in, people would use carbon fiber throwing arms (often from golf club shafts) pretty regularly. It is a good engineered material for that use.
There's no reason to use carbon fiber anywhere else though, since scoring doesn't care about device weight.

If that guy is suggesting that you use a carbon fiber bar as an energy storage mechanism, I would say that there are better ways to store/release energy. Not a typical use of carbon fiber.

[Dark Sabre]

I asked one of my friends who has taken classes in composites about using carbon fiber as an energy storage mechanism.
He didn't think it would be a great spring, but that it would work, if it was laid correctly.

[Flavorflav]

I believe the arms of high-end compound bows are made if carbon fiber, which suggests to me that it must be very good indeed for energy storage.