What do you guys think are the advantages and disadvantages of using an intake similar to tower takeover vs an intake with 4 Omni wheels.
One obvious disadvantage of using TT style intakes is that the chain can break. This can be greatly minimized by using multiple chains, but it’s still a possibility. For this reason my team is going with something more similar to last year’s “chinatakes” where the rollers are geared to the motor instead of using chain so they’re less likely to break
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omni wheels have no advantages.
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TT styles intakes have a pretty big disadvantage since it can’t reach into the mid goals as well.
Using omnis allows balls to fall into the intake, rather than getting stuck on top. Especially when using an omni on top and a traction wheel on the bottom. If set up right, it could speed up the cycle time immensely without any drawbacks.
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actually, I think flaps can be better at this, if you space your flaps properly. flaps let you have superior fielding, faster descoring, and better compression, omni wheels are definitely inferior. TT style intakes are efficient, but lack active center goal descoring abilities, so having separate rollers spaced apart is the best.
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The one issue with TT intakes is the issue with fielding. What differs from last season is that the balls are round, while the cubes are not. So, if you miss with the small intake margin of the TT intakes, your ball will just roll away.
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This would be true if the wheels were static relative to the intakes, however they have rotational velocity. If the wheels didn’t spin relative to the intakes, when a ball falls down, they’d apply a downwards force to the rollers causing the rollers to spin and allowing minimal resistance against the ball. This is desired, but is implausible considering the nature of the intakes.
What this essentially means is that the wheels will constantly be applying a rotational force on the ball and the force changes with respect to the point of contact on the ball and the angle at which the ball hits the intakes. All this to say that those rollers really aren’t doing what you think (at least not very efficiently) and it could actually be worse for intaking depending on the entry angle of the ball.
With respect to the wheel, the rollers are able to free spin. But with respect to the dyanmics of the entire intaking system, the free spin of the roller won’t be doing much in terms of intaking. Free spinning only occurs when a force is applied to the rollers on the “Z-axis” (not sure how else to describe it). *This could be broken down into components for a given force vector depending on the entry angle of the ball. When there isn’t total force on the desired axis, there will be crosswise resistance. Because of this, the “advantage” of an omni wheel is really not an advantage at all. At least not when considering the other intake options which apply much more uniform force to the balls (such options being compliant wheels or tank tread).
TL;DR the rollers on omni wheels don’t provide much advantage in cycle time at all because of the dynamic nature of the intakes. Not sure how else to describe it without diagrams.
Also, please correct me if I’m missing something.
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What you said seems correct, but I don’t have the qualifications to argue with you or verify. I wish we covered this sort of thing in physics 11 lol. Does this help by putting a couple washers in between the plates of the hinge? At least then there’d be more space, no?
Omni wheels are the worst for intakes. The best is with tank tread and flaps which is what all the best robots are doing. Omni wheels are meant to be wheels 
not intakes
I have never had trouble with balls getting stuck on top of the intakes can you please explain what you meant by this:
They aren’t bad, I am switching to tank tread and flaps but omni wheels can work very well if done correctly.
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Im sure there not bad if done right but tank tread and flaps is much better it grabs the ball instead of having to line up PERFECTLEY with the ball when using wheels.
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Flaps do give more reach and grip which is why I’m switching.
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Yep Im already doing a full rebuild and im doing flaps with 16 tooth sprockets
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I am probably gonna go for a china style intake similar to TT. I think the only possible way I can speed up my cycle time is by changing the intakes.
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Nice. Do you think tank tread and flaps is good for the “conveyor” or are rubber band intakes better?
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I feel like rubber bands might make the ball roll more than tank tread and flaps do but i dont know?
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I have tried both, while you can do the tread and flaps, tuning it is very difficult. Rubber band rollers seem to work a lot better as they have less friction and they can give a little to shape to the ball.
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ok so the back peice that holds the balls tight on the rollers should it be smooth or grippy. I think it should have grip so the balls dont roll much is this right?
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