I was asked by my supervisor to learn how to build a basic 2 or 4 chain bar lift with some motor s and 4 wheels . I can’t seem to find no manuals that can help me with this. I only see a Guide for building the VEX EDR clawwbot. Built that already. There are many half second videos out their but they are speedy prototypes. I need something like a step by step guide. Any suggestions?
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I am confused by the question. Is your instructor asking you to build a 2 bar, 4 bar, or chain bar lift? All three are different things.
2-bars are basically the lift you have already built on the clawbot.
The 4-bar is arguably the next step in difficulty as it relied on joints and linkages. This can move keeping the 4th bar perpendicular to the ground.
A chain bar works much like a 4 bar in the sense that it keeps the end perpendicular to the ground, but looks more like a fancy 2-bar. It is arguably the most advanced of these 3.
In my opinion, it is more worthwhile to learn the concept (such as presented in the above video, which is an excellent resource), and then apply it for yourself in your own way than to ask for a clawbot-style manual for each thing.
I am pretty sure better resources already exist than I can provide here, but we, as a community, are always happy to help if you have more troubles.
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Thank you for replying back. The link below is what I’m trying to do, but I can’t seem to see how they put together the bottom part. I can’t get the bottom claw to rise like that.
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So what seems to be the problem? Looks to me like a successful chain bar.
The sprocket on the base tower is stationary, as it should be. It is not attached to the moving arm.
The only problem I see is that the chain is misaligned. The plate attached to the end sprocket (on the moving arm) needs to start parallel to the base tower (perpendicular to the ground).
Edit: oh, I see what your problem is. In the video, the axle running through the gear and moving bar is not linked to the sprocket, as yours might be. To accomplish this, they most likely used the round inserts (as opposed to the square ones) (or possibly, though I wouldn’t recommend it, no inserts at all).
It would help us out immensely if you were to post pictures and/or video of your build so that we can see exactly what the problem seems to be.
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Thanks so much for taking the time out to help assist me. I really appreciated it. Here is my youtube video of what I’m trying to do. Please try not to laugh. I created this video so you can see that I’m trying to create a chain bar lift.
The sprocket should be locked to the first c-channel so that it does not rotate. Also I’d recommend a 12 tooth gear for the motor just to give it more torque.
(Edit) By the first c-channel I mean the stationary one not the one that moves.
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There is also not much support on this system. To make this lift sturdy and not wobbly, you’d need to make two chain bars and brace each part with its corresponding component on the other half of the lift. Bracing on any lift is extremely important. Try to imagine a double reverse four bar or any lift for that matter with only one half. A double reverse four bar really highlights the importance of bracing, but it is a necessary component for any lift.
It seems that you aren’t using this for a competition robot, but rather a proof of concept kind of prototype. In order to successfully make this without two chain bars braced together in parallel, you’d need to use spacers to prevent any metal from grinding against one another and make sure everything is perfectly aligned. Basically, don’t expect the lift to work smoothly even after it’s built well because the aluminum is prone to flexing and things of that nature.
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Also, like shown in the picture above, try connecting the claw on the end with a screw joint instead if an axle
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