Corner Bumpers for Swerve

[dwita.7414]

Hello Chief Delphi! I was curious to find out your thoughts, designs, and tips for corner bumpers with swerve. Tysm for all your input!

[Jon_Stratis]

Personally, I prefer full bumpers wherever possible. With G204 not providing protection in gaps between bumpers, it’s certainly to your advantage to have a bumper there if you can. Additionally, the worst frame damage I’ve ever seen on my team’s robot was in bumper gaps. Obviously, gaps needed for intakes or other moving mechanisms are sometimes required!

[EricH]

I would suggest not using corner bumpers, regardless of drivetrain.

If you MUST use corner bumpers, you literally cannot secure them too well. Ends, corner, between ends and corner… Assume that they will be snagged by the opening and pulled away from your frame, and secure accordingly.

[coderkevin]

Another team for full bumpers whenever possible chiming in here. We had full bumpers for 2020, 2022, and 2023 and love them. So much more solid, can take a hit and won’t get knocked off. I won’t say we’ll never consider a bumper gap, but there would have to be a very compelling reason for us to do so.

[gellnick]

The more bumper, the less chance of your heavily cheeseholed 0.06" 2x1 aluminum tubing drivetrain frame getting whacked into the shape of a different robot’s bumper (true story, we quickly replaced it with .1" non cheeseholed 2x1 tubing and went on to cheesehole something else structurally significant).
In all seriousness though, I’d rather build less bumper parts. Small bumpers have a lot more issues when it comes to building them, especially getting them all to look nice together, while a single ring style or [ ] bumpers are much easier to keep looking nice (lines, not necessarily dirt or beat-up-ness). IMO, building larger bumpers is easier. I also don’t want to mount corner bumpers, seems like something that you’d need a very tough heavy solution for while I could just drop some pins in a ring bumper.
I can see the reasons you might want it, but IMO just the fact that bumpers protect the much more valuable drivetrain structure from major deformation is worth as much bumper coverage as possible.

[Patrick3357]

I’ll be another vote for not using corner bumpers. More bumper means more secure, more protection, fewer mounting points and fewer places to get caught on robots or field elements.

[Skyehawk]

A quick use of the search function is often handy for these types of questions.

Bumpers for Swerve

Corner bumpers have been a not-great option since Week 6 of 2019. (Week 5 of 2019 being the last time corner bumpers had any sort of advantage, of the “give your opponents tech fouls and cards” variety in that case.) Sure, they’re great for reuse year to year. But they need to be solidly attached. And every time you miss the angle and snag 'em, they get less solid/more shredded.

[Richard_Wallace]

If you don’t build a full wrap, one piece bumper, you’re giving up free weight, traction, structural integrity, and robustness against impact. And you’re making it much more likely that your robot will lose a bumper piece during a match, and be disabled.

Corner bumpers shouldn’t be an option. They are nothing but a sucker bet.

[BrendanManning]

I definitely agree with no corner bumpers, but two C shaped bumpers with a pretty small gap between them has been plenty for us* and it also means that you can take them off from the sides rather than needing to get the bumper over the top/bottom.

*We also had a double bumper rail the past couple years, but I don’t recall having issues with impacts my freshman year when we only had one.

[Pizzatc]

I know that everyone here keep says don’t do corner bumpers and I agree with that
But to give you some hindsight about damage even with full bumpers I would look here

Photos of Damaged Bumpers?

This thread has me thinking about our bumper construction, specifically if building in a bit of shock absorption into the bumper is desirable. Our past 2 robots have had bumpers mounted with big chunky UHMW blocks rather than aluminum. Also, our bumpers had a tiny bit of spacing off of the frame perimeter (we did it to allow for some 1/8" gussets to be attached on the outside of the 2x1). I would imagine both of these may have helped us cushion big hits, as our bumpers survived pretty well this…

Now imagine how worse it would be without full bumpers for protection

[saatb]

We ran 2 C-shaped bumpers with a gap for the first time this season after an incident during the previous season where a bumper switch led to us having to stop pushing code changes (we had to disconnect Ethernet in order to put the bumper on).

We took and dished out some very hard hits over the season and had no problem with the bumpers at all, and it was a lot easier to transport them as well. Definitely not a bad option!

[philso]

The type of teams that I typically see using corner bumpers successfully are the (perpetual) rookies that build relatively slow moving robots. They rarely become involved in “vigorous defensive robot interactions” so they can get away with using them.

[JohnV]

We ran corner bumpers this year. We didn’t have swerve. We used the gap to intake cubes on the back side of the robot. We ere constantly getting hooked in our side gaps. It would have been better to run two C bumpers as previously stated by others. Our off season bot was swerve and ran the same bumpers. It was fast and we used the corner bumpers to hook other robots when playing defense. Neither robot was slow and the bumpers constantly needed repair from impact. I do not think we will ever run corner bumpers again.

[mrnoble]

I think that every FRC competitive event (save perhaps Championship) should have a ready supply of four or five sets of corner bumpers with adhesive numbers, ready to be given/shared/loaned to teams that come without legal bumpers. This happens at least once (usually three times) at every regional I have attended since bumpers became mandatory and regulated, and it always results in those teams missing practice day and scrambling to find help to pass inspection.

So while I agree that in most cases corner bumpers aren’t a great competitive option, I think having them is crucial to the success of this program for teams that struggle. To that end my team made corner bumpers to bring to each event we attended last year, and we will do the same this year.

Mr.N

[cad321]

@mrnoble

adhesive numbers

Do you happen to have a link handy to some good material for adhesive bumpers?

Typically we iron on our numbers, which works great when we can take the time at home to do so; But at an event rushing to help a team get their bumpers in a state that passes inspection, adhesive numbers sound like a great option.

[philso]

There were a few teams in our area (like 118, 624, 1477) that are frequently stepping up to help the (perpetual) rookies get on the field. Some of them also brought pre-made corner bumpers, brckets and extra hardware for those teams that didn’t have any bumpers.

[Skyehawk]

Traditionally these are the teams that are almost exclusively running KOP drivetrains with no bandwidth to change/ trade up. Although that assumption is not valid going forward imo.