all medium flaps didn’t pick up the rings as quickly, but all large flaps didn’t deposit them as reliably. Alternating them was a good middle ground, and it seems to work well.
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So as I have started having to attach stuff in correct places and I was winding how you mounted the pneumatic tanks
zipties
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how else???
I mean seriously
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You can cut into parts (c channels, plastic, or flat pieces) to secure a tank. This is often more secure than zip ties, but it adds weight and often is not needed.
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ah, makes sense. now that I think of it, I might have seen someone do that.
I agree, though, zip-ties are better.
I have a question I’ve noticed 2 main types for 6motor drive this year either the 257rpm 4inch Omnis or a 360rpm 3.25 inch Omnis. Any specific reason on using 3.25 inch drive over a 4inch omni drive? i think if i did my speed calcs correct the 4inch wheel 257 is technically faster than the 360rpm 3.25 inch but any clarity on this perplexing question would be greatly appreciated as i may have messed up my calculations.
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there are 2 common ratios on 4" wheels, 3:7 600 rpm (257 rpm), and 7:5 200 rpm (280 rpm). 3:5 600 rpm (360 rpm) on 3.25" wheels is actually faster than both of these, being the equivalent of 292 rpm on 4" wheels.
I chose 3.25" wheels also because I like them more than 4". The mounting holes are nice, they’re more compact width-wise, and height-wise as well. The only downside they have is less traction on the platform, but having my custom traction wheel solves that. 360 is a really nice speed for 3.25" wheels, though it’s very comparable to 280 on 4".
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Was a pleasure teaming with you guys for the first match at kala! Ive enjoyed ur reveals from the past few years and I hope the best for you guys for the rest of the season!
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how is the acceleration between 280rpm 4inch and 360rpm 3.25inch for something such as mobile goal rush during auton?
well, assuming identical weight and traction of the robot, 280 on 4" would accelerate to full speed slightly faster than 360 on 3.25", but that top speed would be slightly lower. The end result being that the difference in goal rush performance is very very small, negligible in most scenarios. From my experiences at Kalahari, I found that I typically tied in the goal rush when facing against 280 on 4" bots with no noticeable advantage to one over the other.
There is definitely a sweet spot with acceleration vs. top speed, and I’d bet that sweet spot for a 6m drive robot weighing around 17-18 lbs (pretty typical for this game) is probably very close to 360 on 3.25" or 280 on 4".
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Ah I see, I don’t really have the resources to make a custom traction wheel like yours so I was considering just using 4inch and the sprocket+chain+tread wheel thing for a traction wheel.
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Hey 99999v,
I and my team are new to VEX. I was wondering if you could help us with showing how your lift works on your youtube channel like where the motor is and how you are able to lift really well. Btw you robot is phenomenal. Thanks a lot!! I hope you read this. PLz help us because our competition is coming up in like 3 weeks. Thanks!!!
I also don’t understand how you made your traction wheels. So I thought you could help us by showing how you did it?
Hello!
First of all, great job on your robot, the design looks sleek and it seems to have performed well for you!
So, I have a question about how your 6-bar is mounted on your robot.
From what I saw in your reveal, and what you stated in the description of your robot, it seems like the six bar and the conveyor are “linked” in a way.
What made you want to do this? Was it to conserve space?
Also, if you could provide a picture of that spot where the six-bar and conveyor are linked, it would be a lot easier to understand, as it’s quite a tight space to look at just with a frame from a video.
no, they aren’t linked in any mechanical way. The shafts sort of intersect the conveyor in a way that lets the conveyor run through the lift towers, but they’re independent subsystems.
the lift is just a simple 6 bar linkage
https://wiki.purduesigbots.com/hardware/lifts/six-bar
which has basically the same functionality as a 4 bar. We chose to use a 6 bar so we could drive the lift from lower on the towers, but this isn’t necessary or particularly advantageous.
I took two HS 60t gears and bolted them together. Then I affixed this assembly to a drill press, and used it like a lathe to cut a slot in the gears like so:
then I ran a ring of chain through this slot:
and then I cut up a 3" flex wheel so I had just the edge part, to get a custom tire
Then I ran zipties under the chain and around the tire to hold it in place.
The reason I did all this is because wrapping the tire directly around a 60t gear doesn’t give it enough diameter to contact the ground. So I used the chain to slightly increase the diameter, as well as giving me a spot to secure the tire on.
I would only recommend doing this if you’re using 3.25" wheels, there are much easier alternatives for 4" traction wheels that perform adequately. It was also a pretty big pain to do and took a few hours as well as a drill press.
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How much traction do the flex wheels give you? Do they add significant traction when climbing the ramp and help when pushing against opponents?
yes, they are extremely grippy on the platform in particular, which is why I made them. 3.25" omni wheels don’t have amazing traction on their own, but with the traction wheel added climbing is very easy.
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