Can we use this part on our robot?

My students submitted a remote skills video and there was some discussion about them using an element from last year on their robot. The consensus was that it for sure was not legal with the rim on due to the thickness of it, so we cut the rim off. They then questioned whether the part was legal at all. They suggest I ask on here. So, tell me what you think.
image (3)

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As far as I know, if it does not exceed the plastic/lexan limit set by the GDC, it’s ok to use during the Changeup Game. Please include the mesurements so we can determine if it’s legal.

(edit): sorry I forgot about the thickness rule, the TT cups were way to thick as to qualify as legal lexan on a robot.

As far as I know, it’s okay. I believe that with the exception of the rims, those are within the right width. Neat design, by the way.

Every question about using a part on a robot can be answered by the Game Manual and Official Q&A.

R10 says a limited amount of custom plastic is allowed, specifically non-shattering plastic.

If the material for the towers is included in that list of non-shattering plastic, and it meets all the other specifications of R10, then it should be legal.

I’m not sure what material the tower cups are made of.

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I believe that most field elements are going to be plastic that meets the material requirements, if not the size, similar to how to flags are legal to use.

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The answer to this question lies in the interpretation of R10 in the game manual, and the specific wording “as cut from a sheet”. Removing the rim of the cup essentially negated the “red box” below R6e about using past field elements (turning point flags were easy, as they were just pieces of already legal plastic according to R10). The problem is that the remaining portion of the cup is not a “sheet”, but rather an injection molded shape. I don’t think anyone would argue that thin walled tubing would not be legal according to R10, even if it was legal material of legal thickness, because it is clearly not a sheet. But as neither a tube (illegal) or a sheet (legal), this may be one of the few cases where a Q&A would be justified for clarification, although I would expect the GDC to rule “not legal” by the definition of a sheet.

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That would not be legal for multiple reasons.

  1. it’s not the legal thickness, I’m sure the TT towers were much thinker than the legal tolerance.
  2. you could not have cut this from a single sheet, as the rule specifies. A molded cup definitely does not qualify as a sheet.
  3. It might not be the right material. I don’t know what the towers were made of, but they could very well not be one of the legal “non-shattering plastics” the manual specifies you can use.
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From the image, it looks like the cups are not one piece, since the tread is going through it.

why would this matter?
r10 states:

Robots may use non-shattering plastic from the
following list; polycarbonate (Lexan), acetal monopolymer (Delrin), acetal copolymer (Acetron GP), POM
(acetal), ABS, PEEK, PET, HDPE, LDPE, Nylon (all grades), Polypropylene, FEP; as cut from a single 12” x
24” sheet up to 0.070” thick

A piece of plastic thicker than 0.07", cut not from a sheet but a molded cup, that may or may not be made of legal plastic (I couldn’t find the material of towers) definitely is not legal.

the legality of turning point flags has nothing to do with their status as former game peices, but because they also happen to be a sheet of legal plastic smaller than 24x12" that is of legal thickness.

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If they have been cut in half, the same result could have been reached by bending a normal sheet and screwing it in to the sides.

sure, but the manual says explicitly “as cut from a single 12"x24” sheet".
don’t think a molded cup qualifies as a single 12"x24" sheet.

and anyways, the other two clauses of this rule would also deem it illegal, as it’s thicker than 0.07", and it could be made of a non-legal plastic.

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Let’s look up the rules:

Does the tower takeover goal look like it is cut out of a single sheet of lexan? no


Thickness = (outside - inside)/2
= (7.8 - 7.75) / 2
= 0.025”
But is the plastic used within the respected thickness range? yes

But personally,
What I believe to be the confusing aspect is this ‘backplate’ seen here formed by the bottom of the TT tower cup:
image
I do not believe it is remotely possible to imitate this backplate with a single sheet of lexan. Even if you come close, you will not have the same result without having additional weight or sacrificed structure. And if you decide to melt a sheet of lexan to achieve such a structure in this image, you will be reshaping the lexan structure with heat which is not legal (you can only use heat to assist in bending lexan).

That being said, I personally believe this would not be legal to use as it may give an unfair advantage.

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I don’t notice that before. Now there’s no question that it’s illegal.

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A TT Tower Cup (276-6089-011) is not legal for use on a VRC robot.

Along with the reasons that others have brought up, the thickness is not 0.025" (0.625mm). That image from Appendix A is measuring two different parts of the cup. The walls are actually angled, and those two dimensions are nearly 4" apart.

The real thickness of the cup is 0.118" (3mm) which is very much not in the acceptable thickness range.

Though, this is not an official ruling. As always if there is debate around something being illegal, it should be asked on the official Q&A.
https://www.robotevents.com/VRC/2020-2021/QA

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