Hood Shooter tips

[stundt1]

Hi CD,
So were thinking about doing a 2 wheel shooter hood like this.
http://www.youtube.com/watch?v=CeA2m...1&feature=plcp

It is powered by 2 fisher price motors (FP 9015) in a Cim-Sim gearbox.
There is a half inch ball compression.
We can shoot at a distance of 20 feet right now.

We made a very consistent prototype that shot 13 out of 16 shots from the key. Yeah for consistency!!!
We are worried about distance as we are hoping to be able to shoot from past the bump.

So I was wondering what could we do to increase our distance?
We were hoping to get around 25-30 feet.

Do we want more compression or less compression then a half a inch?

Would 1 wheel have more distance than 2 wheels?

Sorry, I forgot to take a picture I can probably post one tomorrow.

Thanks,
Steve

[372 lives on]

my suggestion for more distance would be trying different size wheels and different amounts of compression.


if you look at other designs most people used more compression then you are fyi.

[kevin.li.rit]

More compression should give you more distance.

Also more mass on the wheels will give it more distance. (A heavier wheel, spinning at the same speed as a lighter wheel, will have more energy)

Faster wheel will also give it more distance. (more energy)

Fiziks 101. Momentum/Kinetic Energy.

[CalTran]

Originally Posted by Coffeeism

A heavier wheel, spinning at the same speed as a lighter wheel, will have more energy

Though you also have to remember the trade off of not being able to shoot as fast because it'll take longer to build up the momentum

[stundt1]

So more squish then half a inch or less squish. I noticed others had more squish but they didnt have a hood lie the one we are doing.

[kevin.li.rit]

Originally Posted by stundt1

So more squish then half a inch or less squish. I noticed others had more squish but they didnt have a hood lie the one we are doing.

More squish should still help with a hood shooter. Also more contact time with the wheel should help.

If you can take a picture of your prototype you might be able to get more help from people on CD.

[notmattlythgoe]

I've linked the thread to the shooter team mentor. He should be able to give you details on what we have found and what we are planning with our shooter. The one in the video is our shooter from 2009 with a couple of modifications.

[ToddF]

Steve,
Check out this thread: http://www.chiefdelphi.com/forums/sh...d.php?t=101055

To find the answers you seek, you need to do some experimentation. Vary the ball compression on your prototype and see what happens. Vary the speed of your wheel and see what happens. Use the data gathered in your testing in your final design.

[stundt1]

We were talking about this. Would it be better to make sure the ball doesn't slip by changing the wheels to rougher and having the back plate rougher or changing the compression?

Here is a photo of our prototype. Looks a little messy but it works fairly well...
We tested with a CIM motor but we are using a Cim-Sim in actuality.

[jwfoss]

Thats a solid working model for testing. Take some material and add it to the inside of the hood to increase the compression, many teams have found success with ~1.5" of compression.

Another option you guys have is to change the ratio between the CIM and the shooter axle.

Testing is really the only way to see how your setup works. Have fun and remember to watch for damage to the balls.

[kevin.li.rit]

You can also try covering up the holes in the wheel. It will decrease the drag on the wheels and add more mass to the wheels.