Post video of your first attempt at climbing the big one…failure is expected and encouraged! I really just want to see how many teams are doing the Lego 4 bar trick.
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That looks pretty good up until this point, but then what do you do to get that linkage off of Level 1 without pulling yourself back off of Level 3?
And yes we considered your Lego idea when originally posted a couple weeks ago, but couldn’t answer the above question so we went a different route.
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Nice! Thanks for posting, it gives those of us that have yet to attempt some hope!
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At this point we don’t have power to the drive motors…so the robot is not able to drive onto the platform all the way. Of course, when we get some HDPE on the platform, it still won’t be able to drive on! It’s going to be a blast watching all the possible climb failure modes, this year
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Is the initial tilting up just due to non-rigidity in the mounting, or is that part of the design. If the latter, are you planning on leaving that in for the final version? It looks to be helping you get the front of the chassis over the step before hitting the side.
Edit: It looks like the front of the chassis comes very close to hitting the step as is. How precise does your positioning need to be to both not hit the step and not fall back off the ramp? Can you do it with bumpers on the front too?
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Now that’s pretty slick. Thanks for sharing it with the community! I too wonder how you’d disengage it with the lower level after you’re on, but I’m sure you guys have an idea for that 
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I wasn’t certain if the lego four bar method was feasible on the FRC scale, but you’ve certainly proved me wrong. Thanks for sharing this with everyone!
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In this version it is outside the 30” extension, but we have since modified the foot. If you hand turn the wheels on the drive base forward the foot ends up about an inch off of level 1
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It’s part of the design. The student who did most of the design of this mechanism spent quite a bit of time playing with the geometry in CAD, to make that happen.
And he let me weld the parts together (I have a TIG and MIG at home, we don’t have any other welding equipment or expertise on the team)
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That looks awesome! Does the foot just hover above the first platform, or do you plan on further iteration to have it go up more?
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We intend to have it just hover. We have a lot more work to do!
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Our 1st attempt
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Great design! I was just wondering, what motor and gearbox ratio are you using?
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That looks great!
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That’s a nice one! not nearly as "exciting’ as ours.
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That total reduction is about a 2500:1 driven with one redline. It is more than it needs to be and a little outside the recommended loading cases for the Versa planetary. It is a 70:1 versaplantary then around a 10:1 in the tough box. Then a bit more reduction in the chain. This isn’t the best setup under load. The tough box plates end up twisting. We are making custom gearbox, but you might be able to get away with something like this if you put another bearing plate across and do not have a cantilever load on the tough box.
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Team 6911 has not finished our bots yet, but what I can say is that it will be fun to watch ours… if we are not completely on before time runs out, robot tips over.
May as well build some suspense into this years game like robots tipping back and fourth last year
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Thanks! Not quite as quick as the others that are posted, but we are going to work to automate the entire process, so the driver just has to drive on to the lvl1 platform. I think we can get it down to 10-15 seconds.
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One of the best climbs I’ve seen so far. Most reliable and not too time consuming. Nice work!