Goliath Flywheel

I was just wondering if trying a Goliath flywheel, based off the Goliath claws, using rubber bands and sprockets, would work better against the hard balls as it has a squishier surface when compared to traditional flywheel designs. The only real issue I can see is that the Goliath flywheel would take up alot of space. It would make the flywheel be able to grip the balls alot better than the other designs, especially with the hard balls.

Sigh… mind telling us what is goliath flywheel?

And i thought the (nbn) teams had explore almost all the possible flywheels combi… double flywheel (both vertical and horizontal) and single flywheel…

What do you mean by goliath flywheel? A double flywheel? If so then generally double flywheels are less accurate and have a more parabolic trajectory (undesirable this year) than single flywheels.

if you meant using the rubber band rollers (I really dislike the ambiguous “goliath” name…) as flywheels then that really isn’t recommended as the rubber bands will fly outward (due to newton’s first law of motion) and the diameter of your “flywheels” will vary depending on the speed of your flywheel.

Seriously though can we just call these mechanisms what they are rather than coming up with funky names?

I meant using the Goliath claw design as a flywheel, using the rubber bands to grip the surface better as the balls are made of hard plastic for this game. Sorry I thought it was alittle more self explanatory.

The so called goliath intake in itz was a top roller, and not a claw.

And maybe i am just too slow… but i am still trying to figure out which part of the top roller looks like goliath.
So in that sense… it is not exactly self explanatory… at least for me.

But back to the topic, if i remember correctly, there were teams that tried different materials for the flywheels. And so far soft and elastic material has shown that it is not the best for transferring of momentum.

But please feel free to do your own prototyping and try it out. Maybe there will be surprises.

This is important to follow your gut, try it out, you might come up with a solution that works. Part of the process is evaluating the need, coming up with solutions, picking one, prototyping it and testing it.

I found the NbN was actually good for design because there were so many possibilities and refinement just for launching a ball.

Good luck!

You’re right that it’s gonna be harder to get a good grip on the plastic balls, and good on you for using an old concept in a new way.
I don’t think it’s a viable idea, though.
There are two main issues with it:

  1. Reeeaalllyy inefficient and inconsistent energy transfer.
    To accelerate the ball as fast as you need to, the flywheel needs to press against it pretty hard. A solid wheel can do that, rubber bands can’t as well… they bend… that’s like their whole thing. Besides that, when the rubber bands bend, they’ll bend toward the axle which means you have a smaller radius flywheel, which means it’ll be slower. Finally, and most importantly, a wheel is basically just a lever from the axle out to the ball, and bendy levers don’t work very well. Using a solid wheel is like trying to roll a bowling ball using the bottom of your shoe; you just step on it and then roll it. Using all rubber bands is like trying to roll a bowling ball using a slinky. It’s a bad time.

  2. Ballooning
    This is really the killer. Regardless of how well it would move a ball, it couldn’t even really get up to speed without everything exploding and getting tangled up. It doesn’t have to get going very fast before the rubber bands would start bowing outward because of the centrifugal force. Before it could even get to half speed, the bands would balloon out and hit and get snagged on everything around the flywheel. A lot of teams even saw a bit of this with their NBN intakes, and those were barely moving compared to a flywheel.

    Cool idea, though. The main point of vex isn’t to learn which things are good; it’s to learn why things are good, so you’re on the right track by actually thinking about it.

This may be a viable idea, if you have a traction wheel on the same axle to store energy, so that you’d make up for the fact that the Goliath rollers itself has low mass. You would also probably have to use the largest sprockets that Vex offers so that the part that grips the ball has comparable angular velocity. I am deffinitly going to try this, and I’ll probably post the results

Hey guys … just remember that laws of physics still apply along with space management.

Centrifugal force doesn’t exist. It’s called inertia.

Dont forget James Pearson’s Chain flywheel

What are the laws of physics?