Breaking 4 in Vexpro omins

We broke 3 during this weekend at CIR, all just like this one. It appears to happen in auto when we strafe into the hopper trigger plate that’s not under the carpet. The good news is that we didn’t see any difference while driving the rest of the match. The bad is that we’re out the $17.99 per wheel…

Has anybody else seen this with their wheels?

Yup. Same exact issue, the hopper plate. Although we broke them while practicing, never really tried to hit the hopper plates in competition.

I’m assuming when the wheel contacts the hopper plate it’s doing so from the side, rather than head-on? If so you might be able to build a simple guard or skid plate adjacent to the wheel that would protect it from such impacts without affecting drive performance.

These kinds of wheels really aren’t meant for taking direct side impacts, they’re strong in their direction of rotation due to the support from the other rollers, but from the side it’s easy enough to just snap one of the plastic connectors with enough force as you’ve seen already. You might also consider slowing down the speed of your strafe in autonomous (if you have enough time) so that when the wheel does make contact there isn’t as strong of an impact.

You should consider contacting VEX if you haven’t already, they like to hear about new kinds of failure modes with their stuff (helps improve future products). In fact I wouldn’t be surprised if you don’t see someone from VEX drop by this thread.

If there isn’t enough space/weight for protective plates, perhaps cut out some adhesive-backed craft foam to absorb the blow? You could even buy foam that matches your team colors! :smiley:

What am I missing?

Your bumper prevents direct contact with hopper. What is contacting your omni rollers to cause this?

I assume its the plate that is Velcro-ed to the floor right in front of the hopper

They are strafing into a plate that is above the carpet. In can be seen on the left in one of 1678’s photos here.

I see the problem now, thanks. Depending on your design you will need to switch to more robust wheels, I suggest either of the 4" offerings from AndyMark.

Your best bet is the dura-omni as it has a roller that will more likely roll up on the plate. If you don’t have the horizontal room for that wheel, the aluminum FTC offering should be an improvement to lateral stress over your current wheel. You will just need to broach it to fit a hex.

If you ask really-really nice, Andymark may broach it out for you.