We currently have a team that has only a solid 16 in by 16 in drive base that has 4 mecanum wheels each connected to a motor. The code and wheel formation is correct but it rotates slowly. I have been wondering if it is a weight issue as the only weight currently from the v5 screen,the radio,and battery. Base has been tested on many surfaces and has been double checked for resistance but none found. Does anyone else with more experience have any ideas?
you must be moving your wheels incorrectly. send a picture of your base for anyone to be able to help you.
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added a picture of the robot with electronics stripped as the team decided to move on and go ahead and moment a cascade already built on it. They are in the thoughts it will balance the weight
your wheels need to move either move away from each other, or towards each other, I imagine you have one side of wheels. moving correctly but the other side is turning the same direction
so you need to make the back left wheel spin forward, the front left wheel spin backwards, the back right motor spin backwards, and the front right motor spin forwards to make it strafe (either left or right, idk) and then just reverse all the directions to strafe the other way.
When strafing:
left front and right back motors spin one direction
left back and right front motors spin the other direction
Also, you might want to check your config file. Maybe one side’s motor rotation direction is set to false
So then the wheels don’t spin with one side spinning inwards and the other going outwards to strafe?
There’s also lots of great videos on youtube about the subject, from how to properly install the wheels, to a code outline on the algorithm that mechanum drive needs. Hopefully this helps😄
@Ben_Vandeburg, Mecanum wheels come in complimentary pairs: left and right. It makes difference how you mount them. Wheels on your base need to be flipped.
The pattern should look like X from the top and like <> when looking from the bottom.
This is the expected top view:
Also, you may want to switch from 6T sprockets to the larger size. See this topic: Sprocket size for 1:1 gearing ratio - #11 by kmmohn
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is there a specific reason for using a cascade lift? wont it be easier to just build a dbr4?
the cascade lift uses less space thus allowing you to hold more cubes in your robot
also ben, our team didnt go with mecanum wheels for the base drive we plan on useing an H drive (4 omni wheels going forward and one omni wheel perpendicular to the other 4)
ok that was our second option and possible the better one as it would savea v5 motor as v5 motors you only get 8 and by using 4 you use half of them
@technik3kthanks so much that is definitely helpful. I had been trying to figure it out from online but every single source went against the second
The other advantage to cascade lift is it goes straight up and down unlike other lifts that have an arce to them such as a 6 bar etc. the field at least in my opinion is going to be tight space wise and having a lift with arce is going to slow you down.
The DRB4 with correct geometry does deal with this issue as well.