Shooting issues

[akash992391]

Hii
We need help with our shooter.our shooter is not shooting high enough that we want it just go little bit and fell. we try everything to make this shooter to shoot proper distance.....but same thing....I need your help please help us .......thank u.:] :]

[stryker0603]

Describe the shooter please. We can't help otherwise

[Kevin Sevcik]

Details needed. Linear or curved shooter? What motors are you currently using? What wheels and what size? Are you using any gearboxes?

[akash992391]

This moters connected and btw we are rookies soo

[stryker0603]

My guess is that you aren't getting enough torque to make the speed useful or way too much compression. Have you tried 1:1 with the cims?

[akash992391]

Other pic is here

[akash992391]

Yeah we did try

[stryker0603]

Are the discs hitting the bolts you have holding the shooter down? Any idea on what your compression is?

[billbo911]

It looks like the issue is you are using gear reduction to slow the motor output down.
Many teams are directly driving those wheels with the motor, no gear in between. You will get lots of torque, but speed it what you need.

[akash992391]

I don't think is hitting the bolts and idk about that......:confused:

[shadowjm]

Most of the linear shooters that people are using are using an overdrive setup for their gears. It appears from your picture that you have a small gear on the motor and larger gear on the wheel which will reduce the motor output rpm. Maybe try putting a larger gear on the motor?

Regards,

John
37777
Mechanical Mentor

[akash992391]

Can u give us an idea how u connect those directly to motor bec we try didn't work so we have to use gears.....

[shadowjm]

Also you may need something with some grip to it on the opposite wall from the wheels. This will allow the frisbee to spin more. More spin = more stable flight

John
3777
Mechanical Mentor

[shadowjm]

http://www.andymark.com/product-p/am-0320.htm

[akash992391]

Ok and other thing do we have to,have tight enough both side to throw higher frisbee.

[TheMadCADer]

I would highly recommend mounting it so that those bolts aren't there right at the exit. There's almost no way that isn't causing a problem. Try bolting through the side walls above the area discs travel through, or the top surface.

Another issue could be that your wheels aren't lining up well with the flat edge of the disc, so they aren't getting a good contact. If you can get the center of the wheel tread to touch the disc on the flat edge, you should get good results.

Also, I'm assuming you've fiddled with compression and motor speed, but if you haven't, that's step 1.

[akash992391]

Ok we will do that thanxxx though

[cgmv123]

You can use gears if you have to, they just have to be the same size.

[Jorge Ayala]

Our team is getting some awesome shooting distance with just one motor, our shooter design in some way looks like yours. We had some issues regarding the shooting distances so we decided to use the CIM motor without any gears. And we also lifted the tire a little so that contact with the frisbee is made from under the tire (if you want to do this make sure it makes a decent compression). Another way to improve accuracy and shooting distance is eliminating vibration, we are still trying to figure out how to do that, we have already eliminate it to some extent and it has resulted in more accuracy, but we still have some vibration to get rid of.

This is a small (very small) video (https://www.facebook.com/photo.php?v=467284040003465) of our shooter.

Hope the advice helps you.

[dchartley]

If you find the direct drive parts or out of stock at AndyMark, I bought a couple of extra ones and can FedEx them to you. Let me know. Email at dchartley@seattleschools.org.

The sheet metal you are using looks like it may flex a lot. Might try to stiffen up the lower contact surface to that it does not flex while shooting.

Doug

[andrewthecow]

Just to sum up the other advice from this thread and give a little more input, I'd say there are 5 main ways to improve the shooting:
1. Check your compression of the frisbee; too much or too little can vastly diminish the amount of momentum transferred to the disk from the CIMs.
2. Direct drive the wheels using the AndyMark 8mm hub or at least get the gearing near 1:1.
3. Make the surface inside the shooter and opposite the CIMs much rougher, so that energy is more efficiently transferred into making the disk shoot further. My team is using skateboard grip tape for this.
4. Make sure that bolt heads do NOT contact the disks as they exit the shooter.
5. Watch the CIMs as the disks shoot and make sure that the c-channel they're attached to isn't twisting. If it is, it's changing the amount of compression you're getting.

Good luck at competition!

[GilaMonsterAlex]

First thing I would do is speed up the wheels. You need to find a way to make it so. Then I would check the compression, and contact.

[bbuncher12]

In addition to the advice given by the people above, once you get it working well, consider making the second wheel (closest to the end of the shooter) move slightly faster than the first wheel, either with gear ratios or programming. This should allow the frisbee to start spinning and moving from the first wheel, then launch out with a great deal of speed at the second. This greatly helped our shooter both with shooting distance and vibration.

[rwkling1]

what you should try is to make the "fence" (the aluminum on the opposite side of the wheels that the frisbee rides on) closer to the wheels. We made a prototype of a very similar shooter and one thing that we noticed is that you have to compress the frisbee. In example, when you try to put the frisbee through it by hand, it should bend the frisbee. Also, add some grip tape on the aluminum opposite from the wheels, that will increase spin making the frisbee fly farther. Lastly, try adjusting the height of the wheels, to where what part of the wheel touches the frisbee (rounded, apex, etc.)
wish you the best
from team 2977

[runneals]

Since you guys are a rookie team, I'll give you a hint.... Mount the wheel directly on the CIM and add 'squish' on the sides to increase the friction. The greater the friction, the better they fly! We used Rough Top (http://www.leggbelting.com/rough_tops.htm) (blue stuff) when we were prototyping. I personally suggest you do not use rough top, as it tares up the frisbees pretty easily (field damage), but instead search AM & online for something similar that is 'squishy' :) Hope this helps your team out, and good luck!