Sorry about the Round Bumper thread

I did not intend to start trouble and get people upset.


It’s not your fault that this is a terrible website.


Saying anything on chief leads to trouble. You should be greatly sorry.


Guess I will try a different hopefully less controversial one


Wasn’t you who started on the plywood kick.
Perfectly good question to ask.


I’m ok with it. After gleaning though the commotion, I think I know how I would do rounded corners. Still not sure how I would do a totally round robot again but that’s ok. The round robot really sucked from a useful space standpoint.

As far as all the ruckus, It’s just words. Right now there are 32 responses on the other thread I haven’t read yet. I probably will because I’m dying of curiosity.

I learned a little about the high level process (GDC to LRI stuff which frankly I knew nothing about) and went through the 5 stages of grief over the legality of some bumpers we built 6 years ago.

I also learned to appreciate the LRIs who volunteer to be the messengers here and take a lot of abuse for it. It’s got to be tough sometimes.

Things will settle down as usual and hopefully whoever writes the 2020 rules will see this and consider maybe some wording change.

I certainly could use some memes from Matt right now



The conversations in that thread are just going around in circles at the this point. Did you catch that, I made a funny right their.


Yes! All problems are solved by puns!

Well CD gave me the “nice topic” award for this lol and yes it seems to go in circles and IDK what GDC and LRI stand for and as to making a round robot - well I’d 3d print it of course. We are currently working on a conical shaped one that will be used for promotional purposes runs off or a PI or easy robot or whatever else lies around and works and will be used as a test platform first test will be what I think is called and X drive with 4 omnis which lend themselves to a round robot. But for now I guess scratch the bumpers lol or as its not competition we can make the backing out of fiberglass- plenty strong but I know not matching the rule but then its going to be a promotional gig.


Well, might as well turn this thread into a heated debate about whether ‘apology threads’ are acceptable on CD.

GDC - Game Design Committee
LRI - Lead Robot Inspector

Is there a list of all TLAs (Three Letter Acronyms) somewhere? :slight_smile:

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No, wait, here you go:

:smile: That one made my “Funny” folder.

Thanks for all the explanations or TFATE? Well I go back and see if the new sun for my HarmoPlanetary works. Would like to get that done before school starts so I can get the kids on working on a production version. That and how to properly design a HypoCycloid in inventor. I got to know how to do that stuff first before I teach the kids and yeah building a CNC - well never thought being retired is that busy.

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Well, you could always ask about R31c:
“approximately 2½ in. (nominal) round, petal, or hex “pool noodles” (solid or hollow)” :grinning:

I was going to do that last night, but the thread took such a serious turn…

No need to apologize. It is fun and educational to figure out these kinds of “what ifs” on (late) summer CD. This one just dusted off a valid ongoing issue with official / unofficial interpretations of fuzzily written rules. It happens.

Sometimes you learn things about questions you didn’t think you were asking.

I would still build the bumpers. Its a great opportunity to learn about the power of lamination.
I’d point to a couple of real examples:
The Spruce goose
The DeHaviland Mosquito
Most rural Catholic church roof beams
Garage door headers

Here’s the part where I get to boast how we made our bumpers to suggest how to make the plywood:

We cut a bunch of cresents out of 2x4s and deck screwed them down to a table. This is the jig. When done, it looked like a medieval wagon wheel.
Line it with cellophane.
Cut 3 strips 8ft long out of 5mm lauan.
Wet them down with a spray bottle of water to soften them up.
Apply the glue and lay the wood together. We used Gorilla glue, it likes the wetness.
Wrap it around the jig and use ratchet straps to cinch it down. You may need to come up with a way to keep the wood from sliding up the jig.
Let it dry.

This is more than strong enough but if you feel the need to get up to 3/4". add an 1/8" layer of hobby plywood…Done

We made 4 of these layups since 96" wasn’t long enough for 1 bumper and pieced them together to make a whole round. These bumpers (and the remnants) are still floating around the shop and are by far the strongest, well built bumpers we’ve ever made.


That is kinda what I envisioned only difference was that it was 2 half circles as then its also easier to put them on. Only reason I got that Idea is as we are working on that conical promoting robot and theoretical a circle has the biggest area of any shape in relation to its circumference. Besides if you know me I am into spheres. Still looking for the shape of the circumference of the surface of a sphere. surface of a sphere is 4 pi r2 so the circumference of that is 8 pi r if I replace r with t and divide by C4 I got einsteins cosmic constant. So if i take a particle and rotate it around a center it is in balance if i do that I get a minimum of 3 dimension the 2 of the circle and the rotational axis is the 3rd dimension so its in balance and the minimum number of dimensions necessary to rotate something around a center while being in balance is 3 so how do I rotate that particle and around how many axis to describe a figure whose length is 8 pi r (part of the cosmic constant). Now if I spin too fast the R grows if too slow the r decreases but its always in balance satisfying Newton with for every action is an equal and oposing reaction and satisfying time which requires change (movement) Hence in our universe everything moves in an orbit around some center. Asked my teache in 8th grade about that and was told not to ask questions outside the curriculum. So been working on that since then so just to say I like circles twisted and rotated in all kind of shapes. Now there are many mathematical solutions simplest is to just pick a major circle and go around 4x but the question is why and which circle if it is that simple.

Sorry that was not a FIRST related question unless this years task is to build an n-spherical rotating robot lol

When building the promotional circle robot, beware of door sizes. The 2014 robot that we built would not fit through a standard door with out some tilting side ways through the door techniques, commonly used for moving furniture.

One plus to a round robot, is that one person can move it around with ease. This is done by tilting it on its side and rolling it around like a giant cheese wheel.