Do you guys like using rollers and flaps or omni wheels for your hood bots? Which one works better? Is there a design other than these two that works better?
We are using omni wheels and they work well.
You might have to test all of these to see. That would make some good notebook pages.
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neither
previously, flaps were the best option, but now with the legalization of flex wheels, those are probably best.
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compliance wheels have always been ideal for this game
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Right now my team is using flaps and they work fine, However the best option is probably flex wheels now if you have them.
You seem to be the only one saying they successfully made compliant wheels with Vex parts before the flex wheels were deemed legal. Mind sharing your concept instead of implying their viability? This is a forum, not a teaser trailer…
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I have kind of got this to work before, This wasn’t my idea but the way I would do it is by using anti slip mat around the outside edge of a 84T high strength gear, then putting rubber bands around that. As seen in this image (black is anti slip mat, green is HS gear and the yellow is the bands). 
There is also this post Compliance Wheel Intake Design.
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I feel also the foam strips would also be a good addition.
As a team that can’t afford flex wheels right now, we’re using omni-wheels but we plan on redesigning.
Currently we are using a couple high strength gears wrapped in foam and rubber bands. This has proven to be a very viable and effective “compliance” wheel design. Out of the intakes I have personally seen tested and during matches throughout competition, it has been the best intake design. I have not been able to see an actual VexPro compliance wheel intake yet.
These are our current intakes, and so far we have seen them perform better than both flaps and omni wheels and throughout the many months we’ve had them, we have had little to no trouble with them.
Also
We have done this, but the friction mat is very easy to compress, and will remain compressed if held down for extended amount of time. Even with 4 layers of thick friction mat only a few rubber bands were able to completely compress it, at which point the mat becomes basically pointless and deforms.
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Have you tried adding another layer of foam? Not sure how much more compliant that’d be, but I think it’s worth testing.
Another custom option could be rubber links with standoffs for spokes and a polycarbonate ring wrapped in foam.
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Before flex wheels were included in the allowed items, yes. Now, I think the best option is flex wheels.
See: https://www.vexrobotics.com/vrc-flex-wheels.html
We had a rough idea this season, where we would take the rubber off of a traction wheel and use is for the compliance because it was obviously squishy. We even made a “just in case” for attaching it (just in case all other intakes failed), which is tough to explain but the prototype worked pretty good.
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Thanks for the responses guys! I was using flaps, but now I’m going to look into those compliance wheels.
Hey, this is close enough to the topic not to make a new one.
We’re struggling with out intakes, we’ve already had a few iterations that can pick off the ground but we struggle picking out of goals. We want to have intakes that are strong enough to overcome the 6.1" gap in the perimeter goals, but can also reach into the center goal.
We’re working on a omni wheel design at this moment. Should we use tank treats? A full conveyer? Invest in flex wheels?
What I suggest you do from a problem-solving approach is to isolate your issues. Narrow down the variables currently bottlenecking your intake and brainstorm possible solutions to those issues. If you find there are too many variables that can not be readily fixed or isolated –– then maybe a redesign is warranted. There is no end all be all intakes (at least not yet). So keep tuning what you currently have.
To get you started, here are some possible improvements based off the limited context you provided:
- increase intake compression
- increase intake tension force (assuming you have flip out intakes)
- decrease power losses due to friction
- find the torque load on the motor after adjustments and consider a new ratio/wheel diameter if necessary
If you want more specific advice, you’re gonna need to give more specific context. I also suggest you CAD your intakes to properly analyze the geometry, and design around your constraints (i.e. intaking from center goal, maximizing compression at the lip of the perimeter goals without stalling out the motors, etc). From the way you described it, it seems as though your intake geometry is not optimized for your design constraints.
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Thank you! This is immensely helpful
My gratitude
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I think we’re forgetting something
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these are too small to do anything particularly useful with. I could see them being used potentially to fill small deadzones on the intakes or something, but not as the main rollers.
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