Urgent Double Reverse Four Bar Issues

I’m having issues with my 4 motor powered double reverse 4 bar. Whenever I go up the claw tilts left. Whenever I go back down it tilts right. If anyone has any suggestions, that would be much appreciated.1583466291691652260619

Have you double checked that every piece on the dr4b is the same length and the same distance apart to be completely parallel? is one side of your robot heavier than the other? do you have difference banding on one side?


Our dr4b has been working for the season up until this point. I made a mistake in the program and our dr4b make a clicking noise but it looked okay and still worked. About 30 minutes later (after the program issue) an axel popped out of the motor and after that whenever we went up it would tilt to the right and skip gears. When we go down it tilts to the left and skips gears.

Have you checked to see if any of the axles on that side got bent? Or if any of your bracing came loose?

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No, I will replace the axel. Thx for the suggestion.

how many rubber bands did you use
it could be too many rubber bands
mine was doing the same thing and I was only using 2 on each so i took one off each and it lifted perfectly

It sounds like something on the right side of the lift is messed up. I can think of 2 things that might be causing it that haven’t been mentioned yet.

One of the joints on the right side might have gotten damaged and is now causing a lot of friction, (Not very likely, but still possible)

Or, it might be that the one of the right side motors isn’t spinning fast enough and that causes the right side to lag behind the left side, causing it to tilt.

So I’d say, check all of you’re joints to make sure they aren’t causing unwanted friction.
Then check the code to see if there is a difference in speed. If those don’t work, check your motors to see if one of them isn’t moving properly.

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It also could be one of the gears is messed up and might be missing some teeth
I also had that happen to me once and i replaced all the gears for it and it hasn’t happened again

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I had this problem with one of my old tilters as well. It worked fine until one day I reversed it too far and the gears skipped since then.
I think that once the axle has bent once, it makes it more likely to bend in the future, and that’s the problem the dr4b is having

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how i think bending basically works (and i could be wrong) is the point of where said bend is is being heated up just slightly to mold into another shape
but once this happens the structural integrity of the material becomes unstable and is then easier to bend again

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Check to see if you have the same amount of rubber bands on each side if you are using them

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This is what I was trying to say

I will take your suggestion into consideration and try to play with the rubber band amount, thx👍

Thank you for the help. I will take your suggestions and try to use them to help my dr4b. Thx😁

Ok I will try to play with the rubber band amount each side thx for the suggestion😁

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