Inproving accuracy on 2 wheeled shooter

[viperred396]

Hey CD community,

We got our shooter finally mounted up to the robot and it’s getting some incredible range however the accuracy seems to be falling short

What we have now is the shooter portion done (we still need to fab it out of better materials and get the axels true)

The shooter has 2 sets of spinning wheels (currently powered by CIMs via a 1:1 reduction but we will swap them to banebot 775s w/ CIM-u-lators) and the ball feeds up from the bottom. The top wheels are spinning faster to provide backspin on the balls. Also we have ~2in of compression

We have 7 balls, all of them happen to be different densities (similar to the regionals I suspect) and they all fly differently

Any tips out there on how to make the shooter more accurate?
Thanks and see you all at the regionals

http://www.youtube.com/watch?v=fGA45lFcXR4
http://www.youtube.com/watch?v=QcUXnSQvqE0

[Jon Stratis]

Originally Posted by viperred396

The top wheels are spinning faster to provide backspin on the balls.

First, isn't that backwards? To get back spin, you want the bottom wheels spinning faster.

some additional thoughts:

- Only shoot as far as you need to - longer shots are going to be less accurate regardless of what else you do
- try playing with the width spacing of your wheels. You might find that having them too narrow causes them to push the balls to one side or another, throwing off the shot.
- look at how the balls are being inserted into the shooter - is there any variation there?

[Jared Russell]

I notice that you are feeding balls by hand in the video. We have found that a consistent feed (in terms of both speed and centering the ball) is crucial to improving consistency of shots. Even then, the variation in ball compressibility is very challenging to overcome.

[mrnoble]

Hey Bryan! Hope your build is going well today. I want to stop by and see your bot next week. Those were some amazing feeder shots in the first video.