pic: 5803 4513 Double-Climb West Valley

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frc5803
frc4513
doubleclimb

#1




#2

What’s up with the chain path on 4513’s bot? I’m trying to figure it out but it’s stumping me.


#3

It almost looks as if the small one is for actuating the arm and the big one is just some type of hard limit for the rotation of the arm.


#4

That’s a cable protector…


#5

That’s not a a able protector. It’s bolted through on the top like it’s chain and it’s also wrapped around a sprocket at the bottom of it’s run. Also looks exactly like the chain used in the run right next to it.


#6

4513’s cable protectors are at the back. In the front is a fair bit of chain.


#7

It appears that the long chain is fastened at the top of the lift and the bottom. A sprocket is engaged in the middle of the chain. When that sprocket turns, it lifts and lowers the arm by moving the arm up and down the chain.


#8

But why?


#9

Looking at this picture, it seems like the PG71 is powering the sprocket that ‘climbs’ in the loop of chain, making the four bar and intake go up. I’m guessing the two close sprockets are to get a better chain wrap. Really strange but they seemed to do pretty well.


#10

im fairly sure that the lift is not a four bar, at least not like 1778/33’s. https://youtu.be/EmvDj4SMwQ0


#11

I am from team 4513 and yes the chain is used for raising and lowering the arm. We used 2 sprockets, one fixed and one able to move so that as the arm extends in a half circle motion it keeps tension so the chain doesn’t slip


#12

Yes it is, there are two next to each other. 1778 and 33 both have a double reverse four bar.


#13

We have 2 stages to our lifting mechanism, the first stage is a 4 bar system and the other section is a elevator that moves straight up and down


#14

Maybe im just not used to seeing them on an elevator also…

Theres a reason i didn’t help build haha


#15


#16

Because that was the way we decided it would be easiest to do it


#17

Always a different way to skin a cat. We’ve always had torsion issues when we drive an arm at the joint because we want it to move more quickly than it can. Shearing bolts and bending components. In 2011, the Robowranglers had a unique design that fixed that issue and lowered their CG.

I can see how this solution would fix the torsion issue as well.