Any thougts on velcro bumpers or the best bumpers for swerve drive?
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By velcro bumpers, I assume you mean “double sided bumpers with velcro to secure the flap”
They have a long history of coming undone on the field, which will get your robot disabled. The best bumpers for swerve drive are the same as the best bumpers for everything else - the simplest ones.
Using two C-shaped pieces gives you a small number of things you have to make (as opposed to corner bumpers), while still being easy to install and remove (as opposed to single-piece full round bumpers).
Using separate red and blue sets will keep you from having to deal with the complication of double-sided bumpers.
Full coverage (or as full as possible) will minimize the possibility of damage to your robot.
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we had our Velcro come undone many times and we never got disabled. I think it depends what event you are at and how strict they are about that. They most times, just tell you to make sure the Velcro is properly secured.
I think Velcro/Hook and Loop tape bumpers are a mistake. While the possibility of having only one bumper that will never be taken off and can be easily switched may seem appealing, it’s not a good practice. Having one piece bumpers with rounded corners, like @BordomBeThyName said is the best move.
Having velcro bumpers makes your robot more unreliable due to the possibility of being disabled, and with a high contact game like 2022 or even this year, along with maybe being put on a defense role, they’re not worth it. The best bumpers for swerve are durable and have 0 chance of breaking or coming off. Your bumpers are the only thing keeping your robot in play, and are just as important as your battery or your robot itself.
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We’ve used them for the last 2 years (although not with swerve). Haven’t had any issues of them coming undone. You just have to use the industrial strength stuff.
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Then your HR was being nice and violating the rules for your benefit.
G104: Keep your BUMPERS together.
BUMPERS may not fail such that a segment completely
detaches, any corner (as defined in R401) of a ROBOT’S FRAME PERIMETER is exposed, or the
team number or ALLIANCE color are indeterminate.
Violation: DISABLED.
Regional registration costs $4000 and you can get as few as 9 matches in large Regional events. That means that each match costs upwards of $400 to play. Intentionally putting a part on your robot that you know could get you disabled isn’t just completely bonkers, it’s disrespectful of the time, effort, and cost of your alliance partners.
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I agree with everything here, but I have inspected velcro bumper covers that did not come undone on the field. (When asked, one team said they used that design all the time and had never had any trouble with it.) Also, although G104 clearly anticipates disabling the robot if the “ALLIANCE color [is] indeterminate”, while I have certainly seen robots dragging velcro covers, I cannot recall seeing one disabled for it. Does anyone keep a list of robots being disabled in competition?
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Cons: losing matches
Pros: maybe you want to rank low?
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Our VELCRO bumpers never came undone throughout the season. The reason why, we think, is because our bumpers had a FULL strip of hook-and-loop tape on both sides, not like some teams where it was the 3 smaller ones on the left, middle, and right. We also put the opposite side hook-and-loop tape on the underside of the robot to prevent the velcro from catching on the floor and getting us “disabled”.
If you do it right, you’ll be fine.
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My team used reversible bumpers last year and switched to individual full coverage bumpers this year, and I have to say, individual bumpers are a whole lot easier to maintain, they look cleaner, and it’s easier to remove them than to individually rip off the velcro and stuff it on another side. Plus we had one of our flaps get damaged at roboticon last year because it got caught and it dragged the flap under our drivetrain.
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Could you explain how your bumpers are attached? My team currently uses
some form of bolt (positioned vertically) to connect the bumper to the
frame, but we are looking for a more reliable and faster solution.
We also tried with the double sided bumpers but had an issue where they
would come undone and the lose fabric would get pulled into our swerve
module gears.
Not that I’m aware of. FMSField Management System maybe but it won’t say why.
I’ve seen robots dragging velcro get disabled, BUT there’s two ways the velcro can fail and one of them doesn’t affect color (when the flap’s hanging already and the underneath velcro cuts loose).
Sure thing!
Around the perimeter of the robot we have some vertical plates with a slot and a counterbore.
The bumpers each have threaded studs coming off of them, so you lower the bumpers down into the slots, and then tighten a nut into the counterbore to secure them. I don’t have any great pictures, but I circled a few of them here. We used the same system for our 2022 robot, and you can check out the CAD here.
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It happened only a few times driving up the charge station and we fixed the shortly after during comp. Next years bumpers will have tighter clothe to the bumpers so the Velcro doesn’t get undone. I think your making it out to be a bigger issue than it is.
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Thanks! This is exactly what we were looking for.
How are those bolts attached to the bumper? It looks like a weld from those photos.
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Same with us. We’ve run reversible bumpers with velcro and never had a problem with them at competitions. We use full length velcro and make sure the loop side faces the carpet.
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I’ll throw my hat into the (apparently unpopular) “Pro - Double Sided Velcro Bumpers” camp.
In the at least 8 years my team(s) have done double-sided Velcro bumpers, I’ve never once had the Velcro fail to the point where it merited disabling the robot. You might get a corner that flaps around in a match or two here and there, but you just pull out the staple gun between matches and fix the Velcro (or just add more Velcro), it’s not that big of a deal.
Actually making double-sided bumpers can be a pain, which is why we always just get them made at RoboPromo which simplifies the process substantially and seems to be more reliable than doing it ourselves.
As for the benefits of using double-sided bumpers, I’ll point out the obvious ones:
- Switching alliance colors takes just a few seconds
- You’re only required to take them off once per competition (not including any maintenance)
- You can make the attachment method much more robust and simple (since it doesn’t need to be “quick release” or anything fancy like that)
- You don’t need to carry around a 2nd set of bumpers with you everywhere, saving a lot of room in your pit and/or robot cart (particularly if you have large single-piece bumpers).
It’s definitely not something I would recommend for a novice to try on their own sewing machine, but if you have someone skilled enough to make them (or you just buy them premade), double-sided Velcro bumpers can be a great option for teams. To be honest the only, even somewhat convincing argument I’ve heard against them is “they don’t look as nice”.
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Thank you for responses! Appreciate the feedback! 
We have used color-changeable bumpers held with hook and loop for about 6 years and had no trouble. The drive and pit teams really appreciate being able to swap colors in about 15 seconds while rushing to queue. But the design can affect how well the fabric stays and, as others have said, use the good hook and loop.
I agree with this.