I want to do odom for my autonomous program but I don’t know whether I should use 2" or 2.75" wheels. The smaller the wheels the more accurate the tracking is but I was playing around with the 2" wheels and they seem to kinda get stuck from moving side to side in the corners. I was wondering if this is a problem or not. Thanks.
Any wheel works as long as it fits. Make sure you rubberband the wheel down so it has contact.
What do you mean by this? But yes, that would be a problem, as if the wheel gets stuck at anytime that will significantly mess up your odometry readings. If you’re having problems with the 2’’ omni-wheels, I would recommend you use the 2.75’’ wheels.
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I want someone to confirm this but
in this photo I have circled the points that the wheel gets stuck in moving sideways.
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Can you describe what the wheels are getting stuck on?
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Since the rollers are so big for a small wheel the area @spaghettoid circled is where the rollers barely make contact with the floor. So basically the wheel is just dragged.
And it getting stuck really isn’t a problem because it isn’t likely you will be pushed exactly sideways and even if you were, the wheels still work, they just have a bit of friction in that exact position.
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I see.
In that case maybe just transition to 2.75inch omni wheels. The dragging problem doesn’t really seem very fixable in a good way.
is it possibly to fix this by using two 2" wheels that are rotated slightly
Sure it is a bit of friction but can this just be avoided by using 2.75 inch wheels also if you use a gear ratio then they arent even less precise. You can also put a gear ratio on 2" but they are small enough to make that kinda hard and them being that small limits the size of the gear
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honestly I don’t really think it would be a really big problem but if the friction gets crazy high then you could cut the edges of each roller abit
X drive
Another option is to use VEX parts to make your own omni wheels. Ill try and find an image now.
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You are right about it being avoided using the 2.75" wheels. I have just had the problem of finding a nice spot to mount them since they are larger. I also like how the 2" wheels fit it a 2 wide c-channel.
Idk if it has been mentioned already, but the 2 in wheels having the small gap because the rollers are too big causes another problem in that when its pushed to the side it will actually slightly offset the wheel, which can mess up the Odom’s tracking.
Another solution to the 2" wheels could be having 2 per wheel rotated differently. I know it isn’t that good to have a wider odom wheel but if the small diameter is really needed it could work. (I believe the 2" wheels weren’t designed to be used as one. That is why the axel holes are rotated at an offset.)
that it is what I meant. I dont think i made that obvious with how i worded the question. Sorry