Is there a more effective climber for Unqualified Quokkas?

We are opting the Unqualified Quokkas design (4043 to be specific), considering its more robust UTB than the original UQ) for our offseason project.

We don’t like putting a telescope(or an elevator) on our robot, since there’s no COT in our region, and building one is far too complicated, not to mention its difficulty in maintenance and uncertainty in reliability. The original concept on the UQ Ri3d, on the other hand, just isn’t good enough for us.

We are looking for a climber that is either capable of climbing really fast(like 2056), or one that’s capable of doing trap(like 254). Above all, simplicity is our top priority. Any idea?

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On 4788 we used a hook on our arm powered by a neo which was simple but also very fast.

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CC @Andrew_L

I’d reccomend looking at Windham Windup’s robot, and also reading their build blog here:

CAD:

They have a ton of great information and I think they were the best performing UTB Quokkas archetecture (IIRC)

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As spacey-sooty said, our team 4788 made use of a small powered hook on our arm which enabled us to deploy a hook onto the chain, and climb down with our arm. Our robot reveal briefly demonstrates the function. We used a custom servo acctuated ratchet inside our arm’s gearbox. We found the climb to be quite fast at competition. But this may not be necessary if your arm has an elevated pivot point which would be likely with a UTB. In that case a simple hook on the underside of your arm in addition to a deployable ratchet in your gearbox would likely work just as effectively.

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A few notes about our climber:

  • We originally had two 25 chains rotating our arm, but we snapped a chain during practice before week 0 and decided to add two additional chains. If we were to do this architecture again, we’d probably switch to two #35 chains instead of 4 25 chains. WCProducts sells big #35 chain sprockets here: #35 Sprockets – WestCoast Products
  • The gear ratio of your arm is pretty important to being able to not just lift yourself up, but also stay up off the ground for long enough after the end of the match. Additionally your arm motor controllers should be set to brake mode for this.
  • We did not have a ratchet, we just slowly lowered to the ground after match end. A ratchet would work, but is additional complexity we wanted to avoid.
  • The geometry of your arm and your hooks matters. If your pivot point is too low, or your hooks are placed too far out on your arm, you’ll have a lot of trouble staying off the ground.
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[this is our UTB Intake variant of the UQ design]

We just put some teeth under each side of the arm, and then we drive into the chain with the arm raised and then lower the arm. We’ve done it as fast as 3 seconds (a latter version of this removed the two middle teeth, but I don’t have a photo of that handy).

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We are so excited to see that you’re going to be building a UTB Quokka for the offseason and hope we get to see it in action! As for the climb, we are glad to see you avoiding what we did!

The most effective, non telescoping, climbers I can think of, that would work well with the Quokka architecture, are the arm style climb and the ‘hook on chain’ climb.

We were extremely impressed by 9408 this season and their implementation of the arm style climb, which allowed them to be able to score in the trap:

The ‘hook on chain’ climb could be implemented with either; a single mast going through the arm in the centre of the robot, or, by having one on each side of the arm.
Although not a Quokka, 125 used this style of climb with great success:

Good luck this offseason, and let us know if you have any questions at all! We are always happy to help!

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9408 did have a overhaul before worlds which removed the trapping ability in favor of them having a under the bumper

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Our reasoning for the change was that we did not want to have to protect our intake as much as we did with the OTB intake. Also we wanted the robot to look more like Windham’s of course :stuck_out_tongue_closed_eyes:

Loosing the ability to trap was an unfortunate byproduct. If someone has a quokka style robot and wants to build a trap mechanism onto it, this approach might be the path of least resistance.

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