Correcting Mecanum Wheels with Encoders (Ether, We Summon You!)

[lcoreyl]

Originally Posted by goldenguy00

I'm trying to make things simpler by changing the orientation, but I guess I'm doing the opposite. So to drive forward, the wheels all move in the same direction.

<---- (movement from top down)

Forward (<)
[top right] [bottom right]
[top left] [bottom left]

Sliding right (^)
[<--] [-->]
[-->] [<--]

Sliding left (v)
[-->] [<--]
[<--] [-->]

The problem we are running into is that when sliding, it veers up and down. The right top and bottom output velocity values lower than those on the right top and bottom

First off, your wheel spins look to be backwards for the strafes, unless your wheel rollers are configured in an X (worm's eye view). However, you said you can turn normally, so you are likely configured correctly to be O and just have things backwards here??

Have you checked things mechanically before you go correcting things with sensors?
-can all rollers spin freely?

-what happens when you drive at 45 degree angle?

-I have seen both a bad motor and an incorrectly assembled gearbox cause problems that you can't visually see when you put the robot up on blocks and look at wheel speeds. unplugging 2 PWMs at a time can sometimes help troubleshoot this: unplug front motors then rears and drive forward/back, then sides and strafe both ways. compare how far off course you get in each case.

for that matter, can you try to quantify how far off a perfect strafe you are in the normal configuration? Of course, a VIDEO WOULD GET YOU BETTER HELP!!!