Seeking Help with Drive Train Wheel Modification

[SuhJae]

Hello VEX Community,

Our team has recently completed the assembly of our robot’s drive train, and we’ve written the control code for it. In our autonomous tests, we noticed our robot slipping sideways, which, we believe, is due to the omni wheels we’ve implemented to enhance maneuverability. Currently, our robot uses 3.25-inch omni wheels, but we have a 2.75-inch traction wheel positioned in the middle to provide push when going over barriers. We’re contemplating changing the setup, so the traction wheel is always in contact with the ground.

However, we’re facing some constraints:

1. Shipping Delays: As we’re based in Korea, ordering new parts would take at least one to two months for delivery. We’ve already placed an order for the 3.25-inch traction wheel but are waiting for a restocking in Korea.
2. Competition Deadline: Our robot needs to be competition-ready in just two weeks for a local event.

Given these constraints, we’re looking at using the flex wheels we have on hand as an alternative. We have 1.625”, 2”, 3”, and 4” flex wheels. We’re hoping there’s a feasible way to use or modify these for our needs.

What we’re seeking:

1. Drive Configuration Suggestions: If anyone has ideas on drive configurations that would ensure the traction wheel (or a modified flex wheel) remains in contact with the ground, we’d appreciate hearing them.
2. Flex Wheel Modifications: Ideas on how to modify one of our flex wheels to either increase its size or improve its traction characteristics.

Thank you for your time, and we look forward to hearing your insights and suggestions!

[VexTeamZ]

Thanks for the well written post, it gives us a lot of detail about your issue, which helps us help you.

There are a few options I can think of:

• adjust your gearing and use a free-spinning traction wheel. You might be able to change your gearing some, perhaps raising a middle idler gear, and use a 2.75" traction wheel on the lower holes of the c-channel, lowering them to the same level as the 3.25s.
• try modifying your flex wheels, doing something like this:
  3.25” vs 4” wheel traction - #9 by Xenon27
  Obviously not exactly like this, as you don’t have 3.25 tractions, but it should get you thinking about similar ways. Maybe 72t gears…