Chief Delphi

Chief Delphi (http://www.chiefdelphi.com/forums/index.php)
-   Technical Discussion (http://www.chiefdelphi.com/forums/forumdisplay.php?f=22)
-   -   What wheel to use for the flywheel (http://www.chiefdelphi.com/forums/showthread.php?t=154981)

lamk 08-02-2017 23:04

What wheel to use for the flywheel
 
Out team is trying to build a single flywheel shooter. Currently we are using a 4" colson performa wheel that is 2 inch wide. Despite Pid control and trying various compression, our shots are all over the place. Any suggestion on the wheel choice and the amount of compression that may improve our consistency will be greatly appreciated.
Thanks

EricH 08-02-2017 23:08

Re: What wheel to use for the flywheel
 
Have you tried putting a second, identical wheel on the same axle? Or, how about splitting the 2" wheel into two 1" wheels? The resulting "groove" should allow a straighter track through the shooter. It's not an uncommon setup for FRC shooters.

lamk 08-02-2017 23:14

Re: What wheel to use for the flywheel
 
Thanks for the suggestion. We will try that tomorrow.

Fusion_Clint 08-02-2017 23:25

Re: What wheel to use for the flywheel
 
Colson's are too hard this year. Try a soft rubber wheel for your flywheel.

lamk 08-02-2017 23:51

Re: What wheel to use for the flywheel
 
We are starting to think along those line too. I think my team build a reasonably good cage and hood for the flywheel and we have done everything we knew to tweak it. We will look at a softer wheel.

s_forbes 08-02-2017 23:55

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by Fusion_Clint (Post 1642333)
Colson's are too hard this year. Try a soft rubber wheel for your flywheel.

I really want to see slow motion footage of a ball leaving a shooter that has a soft rubber wheel. I'd guess that at the speed the shooter wheel spins at, there is enough centripetal force pulling outward on the wheel that it acts like a hard rubber wheel rather than a soft one.

Ekcrbe 09-02-2017 00:03

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by lamk (Post 1642344)
We are starting to think along those line too. I think my team build a reasonably good cage and hood for the flywheel and we have done everything we knew to tweak it. We will look at a softer wheel.

Try rolling the balls through the shooter by hand, putting them in the bottom and spinning the wheel with the robot powered off. This is a pretty subjective and variable thing, but you want the ball to resist going through somewhat without really getting stuck or sliding by freely. (There also should not be one spot early in the ball's path that is much tighter than elsewhere.) This is a rough indication of whether you have a dearth or excess of compression. If you have too little compression, some balls will probably not catch well and receive less energy than others. Conversely, if you have too much compression, the aggressive deformation the balls are undergoing can make their trajectories hard to predict upon exit.

The equalizing factor, as Clint said, may well be trying a softer wheel that allows more compression to come from the forgiving wheel rather than the balls.

Fusion_Clint 09-02-2017 00:22

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by s_forbes (Post 1642345)
I really want to see slow motion footage of a ball leaving a shooter that has a soft rubber wheel. I'd guess (https://www.youtube.com/watch?v=Fps6S03aWyE) that at the speed the shooter wheel spins at, there is enough centripetal force pulling outward on the wheel that it acts like a hard rubber wheel rather than a soft one.

The flywheel has to grab the fuel consistently and bring it into the shooting mechanism, the colsons slip a lot before actually taking the fuel into the shooting mechanism, resulting in inconsistent velocity and distance.

YMMV, just some results from our tests.

lamk 09-02-2017 00:39

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by Fusion_Clint (Post 1642356)
The flywheel has to grab the fuel consistently and bring it into the shooting mechanism, the colsons slip a lot before actually taking the fuel into the shooting mechanism, resulting in inconsistent velocity and distance.

YMMV, just some results from our tests.

Which wheel will you recommend?

Munchskull 09-02-2017 01:28

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by lamk (Post 1642358)
Which wheel will you recommend?

The new andymark wheels.

theawesome1730 09-02-2017 01:46

Re: What wheel to use for the flywheel
 
Space and weight allowing, more massive flywheels can be more easily regulated using PID. Through conservation of momentum, a large mass flywheel will transfer less of its momentum to the fuel than a less massive flywheel for each shot. It will take longer to reach optimal shooting angular velocity, but will maintain that angular velocity much more easily. If it's possible you may look into that in addition to different wheel surfaces

Cothron Theiss 09-02-2017 01:51

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by Munchskull (Post 1642363)
The new andymark wheels.

Just for clarity, I assume Anthony is referring to these, as well as the other compliant wheels AndyMark has released this past season.

To the OP, a picture of your current setup would help us all dig into the minutia of your design and offer advice, if you so choose.

Tom Line 09-02-2017 02:04

Re: What wheel to use for the flywheel
 
https://www.chiefdelphi.com/forums/s...4&postcount=17

Not much has changed, really.

Richard Wallace 09-02-2017 10:22

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by Tom Line (Post 1642372)

This is why I love the laws of physics. Everyone has to obey them all the time. They don't care who has been elected police commissioner, president, or dogcatcher.

Jon Stratis 09-02-2017 11:10

Re: What wheel to use for the flywheel
 
Quote:

Originally Posted by s_forbes (Post 1642345)
I really want to see slow motion footage of a ball leaving a shooter that has a soft rubber wheel. I'd guess that at the speed the shooter wheel spins at, there is enough centripetal force pulling outward on the wheel that it acts like a hard rubber wheel rather than a soft one.

Our initial prototype used the 4" traction wheels that have come in the KoP in the past (very hard). It worked well enough, but even with only a moderate amount of compression you could hear/see the CIM motor powering it practically stall when a ball went through. Switch that out to the AndyMark compliant wheels, and now with the same setup (same compression, same motor, same gear ratio, literally the only difference is changing one 4" wheel for another) we can feed in a whole row of balls without any noticeable slowdown with the motor. The compliant wheels really do make a difference.


All times are GMT -5. The time now is 20:40.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi