pic: 319's Small Wheeled Shooter

319’s small wheeled shooter for this year’s game.

This, in fact, confirms my hypothesis that a shooter does not need a “middle,” and that a disc can easily ride rails. Thank you for the post. (I do wonder if there is a middle underneath the frisbee keeping the “rails” together though. That “middle” is necessary.)


That “middle” is there. We noticed that compressing the discs was actually causing them to bend, meaning they weren’t touching anywhere but the outer edges anyway, so we took the middle out. It works just as well as our shooter prototypes with middles.

You can do without it. Our original plan was to leave the middle of our shooter empty so our climbing arm can fit down the middle of the robot.

I think the main reason that it works with this design is because the wheels are basically flat, so they can be relatively parallel with the c-channel walls, leaving room for the disk to slide on the base of it. But good point!

Here you go. We still have some playing to do with shooting angle, compression, wheel durometer, and other things. We just couldn’t wait to try it out though.

Very cool implementation, I like the idea of different wheel diameters to get different surface speeds.

I can’t tell from the picture, what motors are you using?

We’re using a 550 through a 4:1 planetary on each wheel. The design was actually inspired by your prototype. Thank you for posting it!

Single motor to control both wheels? If so then that’s a clever way to save weight.

We’re happy it helped. What are the wheel diameter’s right now?

Negative. One motor on each wheel. We felt that coupling the wheels would be a “double jeopardy” of sorts (when the first wheel slows down, it’ll drag the second wheel with it). Also, doubling the power allows the shooter to recover more quickly between shots.

Right now we’re running a 2-7/8" on the first wheel and a 3-7/8" on the second wheel.

Ah. Next question would have been something along the lines of asking the tradeoffs and the worth behind it. How do the Banebot wheels do on getting back up to speed? We just ordered a set for our shooter.

We haven’t had a chance to extensively test it, but we also haven’t been able to put frisbees through the the shooter fast enough to slow it down. Take that as you will.

Have you tried any slighter angles to the ground for more distance? Is it giving them enough push to make it somewhat across the field?
(or maybe that isn’t your goal)

We still have some adjusting to do. That’s why we tried to get it functional as fast as possible.