Launching the ball with wheels???

[cadandcookies]

Originally Posted by heisenburger

My team got the idea of making a claw that ejects the ball with wheels around the centre. Is that even possible??

You'll find out whether it's possible one of two ways:

Do the relevant calculations regarding projectile motion and wheel speed, and compare.

Prototype it yourself and see.

As for how you'll figure out whether it's possible for your team, well, only you have those requirements.

[SenorZ]

Wheels around the center of a claw. Sounds enticing, if not a little vague, too.

Lots of catapults out there, I'm interested in seeing some wheeled shooters. In fact I might just get students to prototype this Saturday.

[bEdhEd]

I would be worried about damaging the ball fabric. Since this is kind of a heavy and big piece to shoot with some high speed wheels, you're gonna need something with enough inertia to not slow down too much while in contact with the ball during shooting. If you need something with a good amount of power to launch this ball more than 5 feet in the air, you might run into problems with damaging, or even tearing the fabric, which is against the rules, and the referees will have to address this during a match. We ran into this problem in 2012 with our shooter since the foam basketballs kept getting shredded up.

This is just my speculation, and I haven't tested this, so take what I say with a grain of salt and don't limit your possibilities. I say try it out if you think it's worth doing, and you'll have your answer soon enough.

[SenorZ]

taking ball damage and inertia into consideration, perhaps an hour-glass shaped roller, with a good mass would be better on each side rather than 2 wheels.

The asymmetrical nature of the ball is also an issue.

[Keegbot]

Lots of the 3 day robots had the intake with wheels, and team O-RYON used the wheels to also score in the low goal. They had another mechanism for the high goal. Wheels will work depending on what your goals are.

[Kevin Sevcik]

Originally Posted by SenorZ

taking ball damage and inertia into consideration, perhaps an hour-glass shaped roller, with a good mass would be better on each side rather than 2 wheels.

The asymmetrical nature of the ball is also an issue.

Hourglass roller would be more likely to damage a ball since the surface speed is different at the different diameters. So you're guaranteed to have slip and scuffing.

[bEdhEd]

Originally Posted by Kevin Sevcik

Hourglass roller would be more likely to damage a ball since the surface speed is different at the different diameters. So you're guaranteed to have slip and scuffing.

Good point there

[SenorZ]

Just read this thread about ball damage. Caution will be the name of the game.
http://www.chiefdelphi.com/forums/sh...hreadid=124416