Best shooter for Shooting Note in a straight line

Our team has designed a shooter prototype that is shooting in a very curved line, probably due to the spin. I know theres a similar thread on here about shooter for a straight line trajectory, but I think the challenge for this year requires something different due to the game piece. Does anyone have a suggestion of how we can make our shooter in a way that it shoots straight, using the least amount of wheels. We have thought about using a belt, but still havent put it in practice.
Link to the video of it working

Using a wheel on each side of the note (either on the sides or above and below the game piece) would probably be the most simple solution, since it looks like you’re already working on a wheeled shooter (?). That’s definitely the most common shooter style this year, but I think I’ve seen mixed success with belts as well.


What is the reason for this?


From prototyping so far, belts are not impressive with grip compared to wheels. Can be Colson, T81, compliant, etc. We wanted to do belts made of surgical tubing originally, but found virtually any wheel to be better. Except for plaction wheels, someone made the mistake and tried those and ripped note in half. Above and below wheels shooter seems to be the straightest we could accomplish without spin.


This is our current leading prototype.


From looking at that video, the arc actually appears to be fairly straight - Given the size and shape of these game pieces, I don’t expect huge amounts of arc from spinning them in most cases.

Your problem is the initial release angle. The note is compressed against the far wall as you shoot it. As it leaves the shooter, I suspect it’s “pushing” off that far wall, resulting in an angle that is left of straight. Why left and not right? Well, as the note goes through the shooter, the shooter wheel is back from the edge a little, while the wall on the right is not. So once you get past that most constricted point, the Note starts to expand - but it can’t expand toward the wall, so it expands towards the wheel, leading its motion in that direction.

Some things to try for prototyping:

  • What happens if you add a second, opposing wheel?
  • What happens if you add a second wheel in series, prolonging the contact period with the Note?
  • What happens if you shorten the opposing wall?
  • What happens if you leave things as they are, and just turn the whole prototype 30 degrees?

There are solutions in all of these that I suspect we’ll see teams employing with great success!


We actually tried it and noticed that after a few time, and then we shortened the wall. After that, we were able to shoot more straight but with less power. We’re gonna try and make the wheels closer together, so it shoots with more power and less compression. Thanks a lot for the response!

More wheels means having them connected or using various motors, we’re trying to use just two wheels but there’s also a prototype with 4 wheels 2 on each side.

Yes, but more wheels also mean more contact with the game piece.

How many motors can you allocate to your shooter?

Two, maximum, due to the way our elet team has planned for our bot. We’re gonna try one that is similar to the Ri3D FUN robot, where they have two wheels on each side, one motor each side, and connect them with belts.

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Care to share the details? Hard to tell your configuration in that video.

Any more information on your setup? That looks much more accurate than most shooters I’ve seen?

Masterful gatekeeping :fire::fire::fire:

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This is unnecessary.


This prototype is using NEO motors at 1:1 driving 2 sets of 4" wheels. The Note is compressed to 9" wide (5" of compression). The biggest driver of accuracy has been consistent feeding, which we’re currently using 4" drill driven compliant wheels.

This definitely still has some variation, but from what we’ve found so far we’re pretty happy!


What wheel are you using for the flywheel?

Our setup is nearly the same as 6045, two sets of Colson 4" wheels with Neos running 1:1, 5" of compression.

(/j if it wasn’t obvious those shots look incredible)

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The first set of wheels that contact the Note are custom wheels using materials from McMaster. Requires pressing in an aluminum shaft with a hex bore broached in it.

The second set of wheels are REV ION Grip wheels.


Gotta love the Fairlane wheels for shooters. Btw Ryan you can use a 3D printed hub just fine, no need go through the trouble of machining a hub out of aluminum and broaching it. We stole this trick from 973 and Adam Heard for our 2022 shooter wheel and they hold up just fine.