We’ve switched back and forth a few times and what we’ve found is that reversible bumpers are very convenient for matches with very little time between them, but generally don’t look as nice as single color bumpers. Additionally, seperate bumpers don’t really take too mich longer to switch if you use latches instead of bolts. That being said, if you do reversible bumpers right they probably would look fine(if you even care about how they look).
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There have been tons of bumper threads on CD, so all the information you could want is out there.
I made reversable bumpers 2016-2022, and we are not going back any time soon. Figure out good mounting solutions and go for the single color bumpers. Single color bumpers are easier to make, more slippery against defense (few seams to snag), easier to repair, less likely to get you disabled, and look better (this can matter in picking). The only advantage of reversable bumpers is fast color changes which is only an advantage if your mounting system is slow, but fast mounting systems are a solved problem (search this forum).
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I disagree with this. There’s a bunch of different ways to do it, but none of them is definitively the best, they often require a good deal of thought and design to implement correctly, and half the time an approach works well for one team but not others.
As a specific example, one year our team tried the 2363 quick mounting solution and they did not work well at all for us, likely because we were unable to manufacturer bumpers to the necessary precision for them to work. I’ve spent too much time reading through bumping mounting CD threads, but I still don’t know what the best turnkey solution is.
For us transporting the robot and pit contents in a single minivan, the space-saving benefits of a single pair of C-shaped reversible bumpers (versus 4 single-color Cs or even a single rectangular full bumper) has been a big plus in its favor, along with quick color changes between matches.
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My team does full, one piece bumpers. As long as your robot stays inside it’s frame perimeter easily, they are much easier to put on and take off than 2 piece bumpers.
In the current era of FRC, asking a single set of pool noodles to hold up to red and blue bumper duty for multiple events is a BIG ask.
I would make separate.
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Reversible can be great but you need a coach/mentor/parent that is good at sewing to do them well. So if you have do that, else just do a pair of colored ones.
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My team, if I remember correctly, has never done reversables. We usually tuck our battery behind our bumpers to keep it nice and safe so it comes off anyways between matches. For Rapid React we had 2 separate bumper pieces, and for Charged up we use one solid piece we lifted over the robot. I honestly love how clean they look and they don’t rip as easily as I’ve heard other teams’ have! If you’re looking for a faster pit time I don’t think it’s hugely a difference, we can still get our robot back in queue in about a minute with 3 people if I coordinate them right.
Drill a hole, drop a pin (assumes you can attach your bumpers by pushing perpendicularly against the robot frame).
2019 bumper
We had little C brackets on the bumpers, and a 1x1 extrusion bar on the frame. The pin prevented the bumper from getting pulled out. The C bracket prevented Y axis movement.
We went with latches in 2020 (as seen in 2363’s video) and i agree that there were some problems if you didn’t have the precision for it. One of our latches was misaligned by a slight bit, and required extra force to unlock.
There is not single best solution, but there are excellent solutions for lower precision mounts, over the top ring bumpers, C-shapes, single side segments, and just about every other configuration. I’m partial to captured nuts and clips personally.
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What would really be helpful for teams like mine and what I mean by “turnkey” is a resource on quick change bumpers for the kitbot that I can hand to a smart student and their parent at the beginning of the season, and then the bumpers come out good. 2363’s resources are what I’d be looking for, but their solution didn’t work for us (to emphasize again, probably because of user error). So we just use Andymark bumper mounting since that is basically turnkey.
Here’s what I said on reversibles a year ago:
Basically I think that reversibles are trading perhaps a marginal decrease in on field performance and more difficulty on the fabric-working side for slightly easier manufacturing and a little less hassle between matches. In our case this tradeoff works out well. For most teams, I would recommend non-reversibles.
OMG I thought the 2022 bot was ours for a sec.
We ran reversibles at least in 2014 and 2016, they worked but we ended up deciding to not use them again, although I don’t know specifics.
We are pretty staunchly against them now, and I am going to echo others thoughts here. The abuse bumpers sustain are already bad enough for a single color, so running one set seems a lot worse. The complexity of them also makes them a higher risk.
If you can do them, all the power too you but be ready to make repairs.
The student who we had in charge of bumpers last year is now our project management lead. I think she has bumpers scheduled to be done next week, which is pretty good since we only just decided on our chassis dimensions.
Getting them early is critical. We’ve all seen/been teams at events struggling to get their bumpers attached to their robots. The later they go, the more they interfere with “last minute” stuff that you wanted to do, driver practice, etc… AND, the less time you have to deal with any bumper issues that come out.
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We had 4 bumper pieces and they were reversible.
No. Use two sets.
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We don’t use reversible bumpers but bumper covers, where one bumper is made like normal and the other is a cover that slips over and is fastened with just Velcro hook and loop around the perimeter of the fabric.
Here’s a picture without the cover.
And with the cover
We’ve been doing this since 2013 or 2014 I think and I don’t recall that we’ve had any major issues with it. It works a bit better with 4 piece bumpers than u-shaped, as the gap is a little difficult to slide the fabric in and as you can see above makes it hard to lay flat. The benefit for us is it’s just one less thing to worry about at comp.
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I think our team is straying away from reversible bumpers as we ran full bumpers last year and were fine. However, we do notice that after a few regionals, each bumper tends to fall apart a little bit so we don’t want to put all that stress on the one bumper.
How do you combat the issue of having one set of bumpers breaking and getting so worn in. We tried reversible bumpers this year and overall, they were ok but by the end of the season, they literally had cracked the wood in two pieces. What kind of wood do you use and pool noodles?
We previously used this method, and I wouldn’t recommend it. They worked reasonably well, but had a lot of issues with the Velcro coming off the bumpers and dragging on the floor. They also took forever to make since we had to wait for a mentor to sew the cover section. They also got pretty beat up by the end of the season. This year we went with 2 sets of 2 piece bumpers, and they worked great. Even with our comparatively slow mounting system, it took 1 person under a minute to change them, and was never an issue for us. They also held up better and looked significantly nicer. Definitely will go with 2 sets again but would probably make 1 piece with quick chance latches.
If you want to use reversible bumpers, you’re probably going to want baltic birch/aircraft plywood for the wood. It’ll be much stronger and stiffer than regular plywood. I can’t speak too much for noodles, but we use solid noodles on our non-reversible bumpers and have never had any issues.
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