Our Drivetrain drifts left for no apparent issue. We have tested many thing such as testing all motors, testing watts used on each motor, checking overall friction on each side, checked for bent axles, checked program, checked for scrap metal in gears. None of this worked and the Drive still drifted left. I will take a video on friday and post it but here are pictures of our drive.
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The only thing I can think of is check the alignment of both of your sides of your drive. Maybe on of your cross drive support bars is miss aligned? In other words make sure that the drive is properly squared, which does look like you did but I’d check anyways.
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Everything should be square, this is a picture from when we started building it
The Drivetrain has not been changed since we finsihed building it.
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My guess is that the larger radius of the omni-wheels compared to the traction wheels, which lifts the robot up a tiny bit, just enough to keep the traction wheels from touching the ground.
Is there any resistance when you try to move the robot left and right manually? If so, something might be wrong with your traction wheels.
After some more observation, I noticed this:
Perhaps that had less friction and your robot was perfectly on top of that.
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We put the tape there to test if both sides spun together, they don’t right side is faster. All four wheels make contact with the ground on both sides.
Pull the shafts out of the motors and spin both sides with your hands. Do you feel significantly more resistance on the slower side?
If so, try to find the problem shaft(s). I spent 3 hours just tweaking shaft cuts, spacer and washer amounts, and bearings. The result was a very low-friction intake.
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These horizontal bracing could be the problem I assume. sometimes the two wheel systems are still parallel, but those bracings aren’t perfectly perpendicular. The same problem is happening to our robot
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Has it been drifting left ever since it was finished? If so you could have a screw on one or more of your wheels that is pulling against the frame too tight which squeezes the gears and wheels too tightly and causes excess friction. I have had trouble with that sort of thing on flywheels. I have also had it with shaft collars pushing out too hard against the inside of the frame
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could be a programming issue asusming your testing of DT friction, motors wattage and motors actually being connected to the axels. also little FYI having 2 HS shafts as your cross braces isnt great. they only have 1 point of connections not 2 which allows for alot more shifiting than a pice of cchanel whcih isanchored to each other pice in 2 places.
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What if your drive starts to flex under load?
If this happens during autonomous portion, you need some sort of control code that corrects the speed of both sides, for example:
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We never tested the Drivetrain only because our field wasn’t set up.
If we decide to rebuild to try and fix the drift we will do this
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We are still trying to fix the drift and I tried some more things today but it still drifts.
I did this and when I put one axle into a motor it caused more friction so I replaced the axle and still the same then I replaced the motor, but it still drifts.
Drift video and drive spinning in slow mo
Slow Mo
Drift (Dual Stick Arcade, Left is Forward/Backward)
In future please try and consolidate all thoughts into one post, quoting previous comments as necessary.
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So i did notice in the videos that the back traction wheel on the right side of your robot seems to be not level almost bouncing up and down. Maybe check that
I will check that left middle motor today in the afternoon.
I will check this thank you.