Flywheel Weights?

Found this flywheel weight from this fourm post talking about flywheel weights in VEX IQ. Was wondering if anyone has experimented with creating a VRC equivalent? Are they even worth pursuing?

I think that for spin up this year most robots would have their flywheels running throughout the match, especially if teams use turrets that autoalign to the net. The low spin up times that light flywheels offer arent as advantageous since a heavier flywheel not only stores more energy but also is more efficient since once its spinning minimal energy is needed to keep it spinning.

Heres what I think a flywheel weight could look like in VRC

Although you could just spin the flywheel faster, there will be an upper limit for how fast you can spin it since the more gears you add the more friction will be generated in spinning the flywheel. Flywheel weights seem like the way to go if you want to save a motor since you could just use one motor and deal with the long spin up time.

What do you guys think? Maybe I’m going insane here idk

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Flywheel weights will definitely make a flywheel more powerful.

@notsockx

So you are not going insane :face_with_raised_eyebrow:

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Well, in engineering terms, no… Power is usually given in Watts. So the power of the flywheel is equal to the wattage of the motor that drives it, about 11 watts per motor. What you decide to do with those 11 watts of power is up to you. Changing gear ratios in your motor affects torque and a speed inversely. The combination of which never gives you more power.

So where does weight on the flywheel come in? This deals with another property called inertia, or in layman’s terms the ability to “not respond to changing situations”. Adding weights to the flywheel will make the flywheel more consistent (not more powerful), the consistency being that every time a disc is launched the flywheel will slow down less because of the extra inertia from the weights.

If an advanced team wants to score more bonus points with judges, calculations of inertia with respect to weight location and radius from the center of the flywheel would be impressive to see in your engineering notebook.

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That is what I meant by more powerful, sorry if that was unclear.

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No need to apologize, I knew what you meant, but as an engineering educator I thought it would be appropriate for the rest of the VEX Community to help understand proper terminology.

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I don’t quite understand the reasoning for flywheel weights, considering that you can only really shoot 3 discs at a time since that is the limit. Unless your system is efficient enough such that the disc on the ground is right after the 3rd disc on your robot, I feel like a flywheel weight really won’t add much. On another note, when you add weight to a flywheel, you will find a very very slow spin up time which will mean you won’t be able to shoot for the first 4-5 seconds of autonomous, or something of the sort.

Note: I am assuming you are doing a 1 motor flywheel

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The extra mass reduces the delay between disc launches. A half second between each launch adds up quick.

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Yes, although giving the flywheel more mass (and therefore it’s rotational inertia) does make it harder to accelerate from rest (as per Newton’s 1st Law), it does make it better at responding to external forces (in this case the feeding and shooting a disc). This is how many teams in NBN were able to get really consistent full-court shots, alongside having accurate velocity control.

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I believe it would be more effective to bolt square steel plates onto your gears instead of adding nuts and screws. This would also keep it compact.

A big issue that you’ll find with added weight is added friction. Make sure to have structural supports on both sides of the flywheel, and use petroleum jelly or graphite on your contact points.

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