How to calculate the exact position of the arm

We are building our arm. How do we calculate the exact position it needs to be to suck in cubes? Our mentor told us a lot of math went into it.

Is this a coding thing or do you want the physical position that is optimal for intaking cubes.

The Physical position.

And the coding if that would be necessary

Well that depends really on your bot, but you wan’t the intakes to be about parallel to your tray.

Ok.Howdo I calculate that and what math goes into it?

Um. I might be confused as to what you are asking. Have you built any part of the arms/towers yet? You can usually just look at the tray and line up the arms with the tray. or you could get a protractor and measure the angle of the tray and replicate that angle when building your arms.

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Yes. We have built the intake. Our mentor told us that a lot of math went into finding the best position for the arm. Can someoene please explain what that means?

Not gonna lie I think your mentor may be over hyping it. There is a lot of experimenting to find the right angle though. Then again your mentor might also be talking about some different coding thing entirely.


Ok. How would the coding thing work and what math (if any) goes into it?

I think we are all confused at this point but the only thing I can think of that involves coding, the position of your arm, and math is a Pid controller which has nothing to do with finding the position of your arms. You are going to have to be more specific.


Is there any math that goes into finding the perfect position for our intake rollers to suck in cubes?


Old post, you may find something useful.

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Honestly I would say just do trial and error. I personally use around 55 degrees

there’s something called protractor. You should be able to get from Walmart or officedepot. You can use it to measure the angle.

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There’s really two bits to this - 1) Finding where the rollers should be sitting for optimal cube intaking, and 2) getting the rollers to that same position each time.

Part 1, not a lot you can do. I would normally recommend trying to calculate it but there’s just so much stuff that goes on that guess and check is the easiest way. Intuition can help however, technically the steeper your tray (less degrees from zero degrees, counter clock wise) the easier it would be to get a cube on your tray. Then you would want your rollers to be as parallel to your tray but that’s not a sureshot way to get it to work.

Part 2, this is the easy part. Once you’ve found your optimal position in programming you will want to reach that position each time you press a button, start a match, etc. You can use the encoders on the motors, quad encoders or just a potentiometer to help make that easier.

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So to recap, there is not much math that goes into figuuring out the correct position for the arm. Our mentor said it was really difficult to calculate the correct position of the arm in order for it to suck in cubes.

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Wait wouldn’t that be the shallower the tray?

You’ve got to build the tray and the tilter mechanism first before you get into the intake. Otherwise you’re jumping the gun and needing to adjust everything here and there constantly rather than going one step at a time. Anything theoretical doesn’t mean that you can just apply math onto it.