Essentially you make a lot of stand-off collar joints. Then on the top level you put standoff collar joints outwards which would hold rubber bands. The main reason is to have a larger diameter.
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if a huge roller isn’t essential to your design, its not worth the hassle imo. just use 2 30t sprocket rollers.
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This way you could save time by making it one piece and increase speed from higher diameter though
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how would it save time?
You make one roller instead of a few
but it’s going to take longer to make that one roller than the two simpler ones.
also that big roller will be less compact, especially in the front where the ball never touches.
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Making the roller piece itself would be but easier to implement sicne you don’t have to connect it to other rollers.
it could be good if your hood is curved around that roller, but most hoods probably won’t be a full curve, they’ll have a lot of straight parts, and a large roller will have uneven compression against a flat section of the hood.
In this scenario itd have a lexan one molded around the curve of the roller
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Welp, just found your solution.
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This is silly
9364b see that idea makes too much sense
That was the intention ethan
This design could work if tuned, my only issue with this is that it seems heavy for a wheel. I know you probably do not have poly-carbonate to work with. I agree, the less steps you have to take in order to shoot a ball out of the robot will help with a faster steadiness of shot and overall balls-in-the goal IF TUNED RIGHT. When building and implementing a larger wheel design, you need to keep in mind compression of the rubber bands. With my hood, I believe it is designed more towards having a larger custom rubber band wheel. Oh yeah also if you were going to do lexan, I recommend finding sprocket with chain/gear to support the lexan from bending from the tension of the rubber bands.
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I don’t think this is a bad idea at all (in principle at least). Simplifying and decreasing the amount of rollers on the robot is usually a good thing (because of friction and other variables).
The main issue with this design is that you’re compensating for angular speed translated to tangential speed by increasing the radius of the roller instead of simply increasing the top end speed of the system through a gear ratio. The reason you’d want to use a gear ratio in this particular instance is because the more rollers the system has, the more control over the balls the system has, and the greater the capacity of the system.
This is desirable for obvious reasons. Having one massive custom roller negates these beneficial properties of a multi-roller out-take system.
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I think he Is trying to mimic team YNOT design with large rubber band rollers if so lexan would be a much better choice than standoffs.
Also i am wondering if you could use rubber tubing instead of rubber bands for added compression.
I’m not arguing that the standoff approach to this design is necessarily good. I’m arguing that the concept in general (really large rollers) is a bad way to compensate for tangential speed given the nature of the game elements.
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If the standoffs are attached with only shaft collars then the standoffs have freedom to pivot witch would make this style of intakes very inconsistent, but cool idea!
I’d imagine you can easily implement physical stops with screws or spacers to prevent that. The same sort of principle applies when you use standoffs and spacers for bracing –– using geometry to rigidly secure the collars in place. I’d also argue that the friction from the screws holding the collars in place is enough to keep the collars from rotating. Though I do agree that standoffs aren’t an ideal solution to increase the radius of a roller. Perhaps custom lexan sheets or even 1xc-channel arranged in a star shape would work better.
TL;DR that shouldn’t be a real issue with adequate build quality
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It is better to have more simplicity so your robot is consistent so i would only ever use sprockets and maybe highstrength gears with rubber bands wrapped around.