Spin Up Ri24Hr - MARC

They don’t list the links of all the legal parts in the game manual. You are expected to go to VEX.com yourself and look up the part(s) in question.

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What size flex wheel is that for the shooter

4”

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now that you’ve had time to drive and play with the bot, what changes/upgrades would you first look to address?

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they took it apart

20cahr

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We’re looking at potentially making a V2 for the Mall of America Signature event (not competing obviously, just for fun)

So far I think the list looks something like this:

  • Fully CADed before hand so we can do some laser cut smoked polycarb
  • Geared up Tank drive (or maybe X-drive, we’ll see how the CAD works out)
  • Smoother intake. The previous build had a pretty big bottleneck at the top of the funnel where the discs had to transition to being flat again, this could be made a lot smoother / faster with some more time to optimize it.
  • Motor powered indexer. The pneumatic indexer worked just fine, but a motor powered indexer might be a bit easier to automate for quicker/more consistent shooting and would last longer in driver practice. One motor could be taken off the intake for this, or some ratchet system for motor sharing if we felt like it.
  • Odometry wheels + GPS sensor for Auton / maybe aimbot if we can get it working well enough.

I feel like there’s probably more, but I can’t think of anything else off the top of my head.

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Turret? If you are in VEXU, then that would be a lot easier with 3d printing.

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Ok so, going back to an earlier discussion in this topic about why you decided to use mecanum wheels. I understand the benefits of using them to better angle your shot, but I was wondering whether or not it would be beneficial to use omni-wheels and an x-drive? I have been looking though the forums but it is still a little unclear to me about the pros and cons of each.

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Everyone is trying to figure out ways to make their flywheel as fast as possible but I think that design has more than enough speed. The high goal is only 25-36 inches above the ground.

Yes it doesn’t have to get far off the ground, but most people would want to be able to shoot from many different angles so probably shot from 6 or 7 feet away at 25-36 inches off the ground, and doing it in bursts of 3 it will really power drop by the third one.

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Can you explain how you finished this robot in one day, what made you do this so fast without CAD? Are there any tips that you can share to increase the efficiency of making robots? Thanks!

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essentially, the main difference between them is that X drive is faster and more maneuverable, but mecanum has much more torque and can use 4 motor drive when going just straight forward. Plus, macanum is overall easier to build and code (although annoying to deal with sometimes), at least I think. People usually prefer X drive because those who want strafing USUALLY don’t need as much torque for their driving strategy. For turrets I’d say mecanum is going to be the meta, but the majority of people say X drive is better.

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Alrighty! Thank you so much.

Mechanum wheels are definitely easier to build, but its worth noting that the code for a Mechanum drive and the code for an x drive are the exact same.

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Did you CAD out the bot before you built it?

We’re also looking into turrets, but we’re doing a couple of simpler bots first to get a hang of handling this year’s game elements.

No, we just winged it while using Wolfpack Machina’s bot as a rough base. Though I am working on a CAD model for it rn.

We first decided what design we were going to build up. Then we split up into 2 teams, one to build the drivebase and the other to build the shooter. Once both were done we mounted the shooter on the drivebase where we wanted, and then started the long process of getting the intake to work.
Overall the bot works a lot better than we expected it to given the time constraints.

As for tips to quicken the building process without CAD, I don’t have much. I know it’s not super helpful but personally I think the biggest thing you’ll need to build a bot quickly is just having a good amount of experience in building bots with good build quality, and having past experience building mechanisms similar to the current one you’re attempting doesn’t hurt.
As for something that might be a bit more helpful, I find using an electric screwdriver helps save a lot of time tightening nylocks down, and developing your own tricks to getting a nut onto a screw in tight spaces can save a ton of time as sometimes just getting the nut started takes many times longer than actually screwing it in. And of course, having at least a rough plan for how the bot is going to go together and everyone being on the same page with it is a must.

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What material did you guys use for the outside curved wall?

As for CAD, does anyone have the CAD files for all of the various types and sizes of flex wheels? I tried adding the files from the VEX website to my parts library on Fusion 360, but my computer reads them as “corrupt” and will not upload the files. The .STEP files are what they download from VEX as. Does anyone have the files that are not “corrupt” or that are in .F3D format?

What iterations did you go through designing the intake? Specifically, what did you go through for the first roller and back plating, the part that flips the discs up off the ground? Any tips or warnings?

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Why did you use two motors on your flywheel? Would one have worked? Or did you just do two because you had one extra? 100th post btw.

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