Curve of contact in shooter

[leolagos]

Our designing team is thinking in making a change in the typical wheel shooter by making the spining part of the shooter with the same curve of the ball (Something like the 973´s shooter in 2012). In our heads, the more points of contact with the ball and also the "walls" that will this shooter have, will be better but in contrast there are just a few robots with that kind of shooter.

We are wondering, what are your thoughts about using a mass with the shape of the ball (fuel)?

[Southpaw]

If you are a team with the resources, go for it. Otherwise I feel you should not bother. This game is much more short range and will not require as much control over the ball.

[BJC]

This is not a good idea. When different parts of your shooter wheel have different diameters, those different parts also have different surface speeds. This means that if the ball contacts the drum in a slightly different place on the wheel it will attempt to propel the ball faster or slower. In the past with foam balls, this was really really bad. With a harder game object it might not be as detrimental to accuracy, but it will almost certainly not have any positive effect.

Cheers, Bryan

[leolagos]

Thank you for your replys.

We understand that there are different speeds depending on which part of the rotating mass you measure. But if the curve were designed to contact the ball in "only" two points (and not half ball or something like that) ? Having the benefit of center the ball and also another point of contact to transfer the energy to the ball.

Something like this (very quick design to think in that option):

http://imgur.com/a/Y0e4F

[Ekcrbe]

Originally Posted by leolagos

Thank you for your replys.

We understand that there are different speeds depending on which part of the rotating mass you measure. But if the curve were designed to contact the ball in "only" two points (and not half ball or something like that) ? Having the benefit of center the ball and also another point of contact to transfer the energy to the ball.

Something like this (very quick design to think in that option):

http://imgur.com/a/Y0e4F

The problem with this is that if a ball comes into your shooter slightly off-center, one side of the wheel will contact the ball sooner and compress it harder than the other side, and will forcefully try to recenter the ball. It probably will be able to do so, with the downside that the ball just spent the entire time it was in the shooter moving sideways as well as upward, and it will continue on that sideways trajectory as it exits the shooter. We started with something like this in 2012, and scrapping that design was the best decision we made all year.