Lift assistance

Before you start commenting about how this thread has already been answered 10 times already just listen.

I know both of the pictures are sideways, but it is hard to take a picture with a chromebook.
IMG_20190214_182148 IMG_20190214_182029

As you can see from the second picture, the lift is not able to stay completely vertical. This effects it both when the lift is fully rested, fully extended, and everywhere in between. I imagine the culprit is the lower joint in the first picture where a bearing block is mounted closer to the arm through the use of spacers.

If this is the case what could I do differently? Do I need to get screws longer than the vex 2" to fit the gap better?

This thread has already been answered 10 times. :wink:

Are your 4 bars in each stage built the same? I tried to holecount it (not accurate with glare, probably) and saw that the first stage was 10 hole spacing between the joints, and the second was 9. No clue if that’s right or not, but it’s a thing to check. I’ve miscounted holes before.

When you say not vertical, I assume you mean it’s not linearly lifting, and the top stage leans forward, right?

Both sets of bars are built the same, and yes I meant linear lifting. The fact that it does not lift linearly then causes the top stage to lean forward.

Could it be that your gears aren’t meshed so that all bars are parallel at the midway point?
Your bottom stage has a gap, while the top doesn’t in the fully raised position.

Yes the top stage gears are offset to the bottom stage gears, but there is no way to make them perfectly in line with the 60 tooth gears (or any gears divisible by 4).

This is correct. I would say that this is the issue. If you offset the gears the opposite direction, (as in, toward the top rather than the bottom) does that help?
Getting gears meshing right is a pain in DR4Bs. Might be an extensive process.

If I offset them in that direction many parts of our robot will not work properly. The offset as it is currently would make it more parallel when you factor in weight of the lift compared to what you are suggesting.

In addition to this wouldn’t offsetting them in that direction move the weight towards the front more, further worsening our problem, especially once the lift is all the way up.

Would it? Maybe I’m thinking backwards. … Yep. You’re right. Sorry.

I’m not sure then. It could just be the weight of your intake. Maybe rip that off and see if it work properly without it. I’m not sure what else to tell you.

Ok I’ll see. It may very well be the intake as it is rather bulky. I might prototype another version of it before state.

I would also like to point some attention to the lower joint seen in picture 1. From what I understand it could very well be our culprit.

@Got_a_Screw_Loose And thank you for being willing to provide some input. I was afraid many would get frustrated by another post asking for help on a DR4B lift (and rightfully so), but I think we can both agree this was something different.

Not completely, but, from my experience, you would’ve had to scrounge around 5 or more extensive threads to find ideas to test.