Crossbow like ball launcher
 

So our team has an idea of making a crossbow luancher to launch the balls. We're thinking of using metal springs to luanch the ball and to pull the strings back we are using a motor that will pull the ball back then will attach to a hook that we can then release for luanching. Will this even give us a good distance and has anyone else tried this.

it wont neccesarily have limbs, we're looking at attaching the springs to a frame that will be connected to the ramp the ball goes down something with a board underneath that will connect the ramp and the frame and we will load the balls through the front with a conveyor belt that loads to the ramp and then a motor will pull back the springs and then WHHOOOOOOOSH. :)

Re: Crossbow like ball launcher
 

How are you planing to load the balls? If you don't have a loading mechanism I suggest that you figure that out first.

Re: Crossbow like ball launcher
 

Just my 2c here.

Be careful about complexity. My team still runs into things where we take real life scenarios (Crossbows), and then try to translate them into robots. I think your difficulty will come with a latching mechanism because they are inherently harder to get working (Holding 100lbs force but using 2lbs to release).

I don't know how advanced your team is, but a "Ball pitcher" will be a lot simpler mechanically because you just feed the ball in and boom its away.

:-)

Joe

Re: Crossbow like ball launcher
 

My team's two options right now were a pneumatic catapult, and something similar using springs (dep. on if using pneumatics will end up saving weight). Instead of a crossbow with limbs, maybe just a spring being ratcheted back?

Re: Crossbow like ball launcher
 

If this idea works, I love it. I'm trying to push my team to build a catapult this year because of the better chances of scoring, but the main concern is that a catapult isn't accurate enough. A crossbow would solve this problem.

Re: Crossbow like ball launcher
 

Check out team 1523 (MARS) at the Florida Regional in 2006; they used something similar that was very effective. Videos available on thebluealliance.net.