Anyone got photos of bumpers that suffered damage this year? External or internal.
I think the hits this year might have been the hardest we’ve ever seen. Looking for the evidence.
Mr.N
I dont have a picture but our bumpers defintely were far more damaged than they were in previous seasons. We took a hard collision at TT that ended up damaging them so much that we had to use our red bumpers with blue gophers tape for the finals. What happened was a corner with wood screws tor apart through the wood
Maybe this lines up with what you’re interested in?
I don’t have much context besides that this happened at SoCal Showdown, I believe we had similar bending issues (maybe different root causes) at Houston, and our frames are 1/16" Aluminum. Not sure about bumpers.
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I think I found the root cause right there.
You CAN get away with 1/16" aluminum, given some bends and possibly some extra bracing. But using it in the drivetrain scares me pretty bad. Even with bumpers, I vastly prefer 1/8" wall tube at drivetrain level–1/16" is IMO best used farther up the robot.
It wouldn’t surprise me in the slightest if this sort of damage is also a contributing factor to the “no more than 4 motors driving the robot” rule for next season.
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We haven’t analyzed this situation to my knowledge yet.
But from what I’ve heard, buckling and wall thickness is playing a part. We’ve used 1/8" for the past couple of years (disregarding this one) but I don’t remember why we changed that.
We’re you guys using standard 2x1x1/16 or were you using the kind from Rev
No, it should be standard 2x1x1/16" that were custom drilled.
Again, we didn’t analyze this one yet so I’m not fully sure what happened here not do I have all the facts on hand, but yeah.
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Why the 1/16? Weight down low is good, especially this year.
I am pretty sure 3357 has had to rebuild bumpers in the past, at least I think @Patrick3357 mentioned it.
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@Cirrusx do you have photos of your B team’s bumpers splitting in half from Bordie? Definitely was something to be witnessing field side.
@AndreSanchez955 I feel like there was a moment you guys sustained some pretty heavy bumper damage from Sundome, please correct me if I’m wrong- do you have photos if you guys did?
Yeah we broke the corner joints on our bumpers before MSC I don’t actually have any pictures of the damage. The bumpers would actually stay in place just fine and did not appear damaged when installed, they just didn’t provide the structure we wanted anymore. If fact we ran most of MSC with broken bumpers, before I could get replacements made for CMP. We used a mix of 1/16”, .040” and heavily pocketed 1/8” tubing in our drivebase are relied on the bumpers to provide strength.
The thin plywood Ls broke and the glue joint failed between the main pieces, but the main plywood pieces were completely undamaged.
@banjogates has the bumpers and might be able to get a picture if he’s still checking Delphi.
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Do y’all agree with me that the recent trend has been toward higher speed impacts and a need for better bumpers? We broke or tore several sets this year
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Yes. At our first competitions, we didn’t have a bottom support plate on our swerve. We cracked our bumpers and bent a swerve module top plate down to the point where the tread was almost touching our bellypan.
I’d say 2023 seemed to be particularly tough on bumpers, but part of that was a particularly aggressive driver. I can see a general trend, but not a massive one, and I think that comes down to faster more powerful drivetrains more than game design.
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I went back and reviewed video footage of the fastest games I can remember, especially 2014, with the wide open field, and compared it to the pace of 2022 and 2023. At Einstein 2014 it looks like the fastest robots are going at about 1/3 the speed of the robots in the finals at Chezy Champs 2023. In fact Chezy looks to my eyes like the footage must be sped up for comedic effect everyone is moving so fast.
This and a few decades of lessons learned about robot design and how to drive.
Yeah, 2014 was a wide open full contact game, but just from a different technical era. I bet if we played 2014 again with modern technology it would be worse for collisions than 2023.
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I’ve got some photos! My team had to replace a chassis rail and rebuild bumpers multiple times this season. I think the hits were harder this year than in any other year I’ve been around. For us, I don’t know if it was our aggressive driver, playing more matches, being a more likely target for defense than in the past, the steel belly-pan in the bot… or some combination alongside access to brushless motors and the game design. We even made a video about it. These photos are mostly from after our 2nd regional or the July off-season event we played. Photos were taken while dissecting the bumpers.
Here’s assembled bumpers installed on robot. We felt pretty good about our bumper assembly going into competition. We are plan on making some changes to how we assemble/reinforce chassis rails and bumpers in 2024.
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We had a lot of tears in the fabric this year. Prior to this year we had 0 tears. Not really sure what it was from. Will edit post with images later.
We mostly suffered from tears in the corners. We had to fill in our bumpers with more foam prior to a match at Detroit. Most of the tears I suspect were from running along the charge station.
While I like Rev Products, from what I have seen and read about with their extrusion material I don’t see it being suitable for chassis frames. Its obvious that while its convenient for robot assembly the thinness of 1/6th inch material along with the impact forces that a chassis takes I would not use this material for a chassis. I would stick with 2X1x1/8th. From the pictures I see the failure points are all along the extruded and machined surfaces. There are too many stress and weaknesses points in this material. The extrusions should be used elsewhere on the robot where impact is limited. These failure points as can be seen in the photos right along the holes, groves and non-braced/re-enforced areas.
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