Round Corner Bumpers

Hey! Our team is In process of re-making new bumpers for the upcoming regional at San Jose(SVR) since our old bumpers were not the best :o
But I was wondering how some teams get those clean round edges on their bumpers!
I’m not sure if it depends on the way you wrap the fabric around the bumpers? Or the pool noodle placement?

Teams Bumpers that caught my Attention:
254
295
973

Once piece of pool noodle, cut to the height of the bumper, put on the corner in line with the other 2 noodles, one bumper cover goes around the entire thing. It looks great!

We bent the pool noodles right around the corner

The best.

I like the placing a pool noodle on the corner idea, but we’ll have to test both to see what results we get

-Thanks Guys!

Agreed. We bend them around the corner too. Spay glue helps hold the noodles in place against the wood. Here’s the only photoI really have online of the finished product. 1-piece bumper.

This compresses the noodles in the corners, thereby reducing their shock absorbing effectiveness. If done too many times, we may see rules against it, despite how slick the result looks.

We prefer cutting the pool noodles at a 45 degree angle to give nice, crisp corners.

Why even suggest this? I have never seen one instance of any bumper constructed in this format failing or not adequately protecting the robot.

for one it doesn’t follow the letter of the bumper rules. I bet if you measured the protection of the corner you would have less that 2.5" of noodle between your wood backing and your fabric. The GDC went to great lengths to have multiple pictures of what was legal and what wasn’t. I understand that doing it this way allows for more room in the 54" cylinder. No need to bite the guys head off for suggesting something that is rather straight forward.

As far as I can tell, R27 says that the corners must be protected, but does not specify the width of pool noodle needed in the corner.

What rule are you reading? The closest that I can find is R24-C, which specifies the size of pool noodle and the maximum thickness of the bumper, but not the minimum thickness.

R24-C use a stacked pair of approximately 2 ½ in. round, petal, or hex “pool noodles” (solid or hollow) as the BUMPER cushion material (see Figure 4-4). Cushion material may extend up to 2 ½ in. beyond the end of the plywood (see Figure 4-2).

Ok, so allow me to take this to an extreme. I start off with normal pool noodles. I then compress them repeatedly so they are no longer 2.5" in diameter. I then use them to create a set of bumpers that are significantly smaller than those used by most teams. This gives me roughly one more inch of robot length than a typical competitor. In your reading of the rules this would be allowed.

regardless,

Rule r27 and diagram 4-5 is where I am seeing the issues here.

http://frc-manual.usfirst.org/upload/images/2013/1/Figure4-5a.jpg

it defines the width of bumper material as 2.5" around the corner.

What I understand from that picture is that the pool noodles need to be 2.5" in diameter on the sides, not on the corner. If they had wanted the corners to be 2.5" wide I think they would have shown a dimension from the corner of the wood backing to the outside of the corner pool noodle.

How are you getting an extra inch of robot length? The bumpers don’t enter into the robot frame size rules.

I’m sorry. I was referring to the 54" cylinder rule in this years game.

I think we need to look at the intent of the rules here? There are these bumper rules in place, correct me if I am wrong, so that the robot and frame are protected, in addition to providing a way to identifying teams, and what alliance those teams are on. The bumper wrapped fully around the corner does protect the robot, and if all of the rest of the bumper rules are followed, than it meets the three goals that of the rule.

It’s amazing how many teams fail inspection every year that have functional bumpers that fulfilled all the things you just mentioned.

A rule of thumb used for many years is to punch the corner of the bumper. If you can feel hard parts then the bumper does not meet the rule. The drawings are very specific with dimensions included.

We pull the pool noodle tight around the corner (single peice), then pull the fabric tight around that. This has been the cleanest way that we’ve encountered. There is a consistent 3.25" radius around the corner so there is no lack of protection.