pic: Robot Bumpers

[rjohnson]

What would be the point of building a robot with this configuration? I don't know who likes to use less space than they are given to build their robot. Going to this much trouble to add a few extra degrees for trailer movement doesn't make any sense either. Can anyone enlighten me with why this design element is so important?

Also, anybody who wants to do something like this should be careful with <R18E>, which refers to damaging the trailer tongue with bumper contact. If you REALLY wanted to make something like this, I guess you could make it rounded as long as the tangent to the bumper near the trailer is parallel to the side of the robot. It would be much more difficult to fabricate though.

Just to go along with what everyone else is talking about, I think that this configuration is illegal because of the "both sides of the corner" rule. However, I think there are other questions to ask first.

[T3_1565]

Yeah, this bumper stuff is getting to be very frustrating.

From the way the rule was written I understood it as "We don't want any part of the robot exposed because of the high speed ramming that will occur, so bumpers must be on every corner to ensure there is little damage caused to the field and other robots". This is understandable.

I do not see how ANY part of the robot shown above could make contact with another robot (that is also following the bumper rules) or the field in a way that "the bumpers must make contact first" would not apply. Yes, corner A and B are not covered on both sides of the corner, but at the same time, it is impossible to reach the uncovered side of those corners.

It seems almost like things went a little overboard when making these rules, We might as well just build our robot out of pool noodle wrapped bars, or wrap the whole robot in bubblewrap, with the way this keeps going.
2cents.

PS. to follow what seems to be what the GDC wants, I would also suggest putting bumpers on the inside corners of D and E, as both sides of those corners will also need to be protected.

EDIT: I hope that inspector manual comes out soon, so we can build our robot lol

[MikeDubreuil]

Dave, I looked carefully at it and I can see where you are coming from now.

Figure 8-2 (Blue Text added by me)

Originally Posted by <R08-J>

Corners and joints between BUMPER segments may be filled with short pieces of vertically oriented pool noodle, by wrapping the pool noodles around the corners, or by beveling the ends between adjacent segments so they form a tight and complete protective surface (see
Figure 8 – 2).

GDC Q/A Response, "both sides", "curves"

My Pro-GDC Analysis:
What you are supposed to infer from <R08-J> is that the Figure shows how to protect corners A, B, C, and D. The figure clearly demonstrates "both sides" of the corner as being protected.

My Dissent:
As a general rule of thumb- the GDC should not provide a figure as an example for a rule that violates other rules in the manual. This definitely creates confusion. The other part of the figure 8-2 which creates confusion is corners E and F. These two corners apparently are not corners and are in fact "curves." From the Q/A response, the GDC will not define a curve.

From that my friends, I may make without hesitation and purely for intellectual and kindly debate that I make this claim: In the Scott Hill Image corners A and B are not corners and are in fact "curves" making this configuration LEGAL.

[johnr]

That picture only shows techniques for mounting bumpers. Trailer hitch could just as easily go b/t a-c or b-d.

[dlavery]

Originally Posted by Scott Hill

Would you do me a huge favor and review the thread "is this corner considered protected" and point out any flaws in my attempted logical analysis of this issue?

If you would it would be greatly appreciated.

No. For the simple reason that ALL discussions and debates here are meaningless. They carry no official weight at all. If you want a determination on the legality of bumper configurations, do what has been suggested (multiple times, both publicly and via PM) and submit a particular, specific question to the FRC Q&A forums. Get your real answers there.

[Aren_Hill]

Originally Posted by dlavery

No. For the simple reason that ALL discussions and debates here are meaningless. They carry no official weight at all. If you want a determination on the legality of bumper configurations, do what has been suggested (multiple times, both publicly and via PM) and submit a particular, specific question to the FRC Q&A forums. Get your real answers there.

he's tried twice....

http://forums.usfirst.org/showthread.php?t=11361

http://forums.usfirst.org/showthread.php?t=11204

no useful answer

[Matt C]

Originally Posted by Aren_Hill

he's tried twice....

http://forums.usfirst.org/showthread.php?t=11361

http://forums.usfirst.org/showthread.php?t=11204

no useful answer

The better question to ask would indicate the exact configuration intended to be used, with illustration, and ask if it is legal per the rules.

A picture is worth 1000 words.
Without a completely clear indication of what the design is, (no ambiguity as appears on the second question posted) it would appear hard to give a definitive answer without opening up the door for discrepant designs based on that answer (to an ambiguous question).

I'm sure they would get a useful answer if they provided the illustration to the GDC that they provided to us.

[jgraber]

Originally Posted by dlavery

and submit a particular, specific question to the FRC Q&A forums. Get your real answers there.

Except that specific examples are discouraged at Q&A, they want only rules clarification rather than pre-inspection.
I'm exploring theoretical ways to use the bumper frame as 18 lbs of robot frame stiffener. There is no limit on how far inside the robot perimeter that the bumper side of the interlocking brackets can protrude, right? Only a 1" limit on how far outside the robot perimeter for bumper hard parts.
So a 28x38 piece of plywood the shape of the robot frame, with holes for wheels, etc, with bumper plywood mounted to the edges, is all considered bumper mounting hw, and as long the whole thing with foam and fabric and bolts weighs less than 18 lbs, its legal, and could be used to stiffen the frame of the robot. Sound good? To remove the bumpers, pull all the bolts, drop the bumper floor, and lift/drive the robot out of it. Has anyone weighed a 28x38" full perimeter bumper yet, to see how generous 18lbs is?

[Jared Russell]

Anyone else have a head ache?

[T3_1565]

lol... you have no idea... I'm trying to keep track of all this stuff for my team (they are focused on other things besides bumpers right now.. lol) and hopefully our design doesn't end up breaking some bumper rule (as of right now it doesn't but who knows?)

[Collin Fultz]

Originally Posted by jgraber

I'm exploring theoretical ways to use the bumper frame as 18 lbs of robot frame stiffener. There is no limit on how far inside the robot perimeter that the bumper side of the interlocking brackets can protrude, right? Only a 1" limit on how far outside the robot perimeter for bumper hard parts.

Except that R08-L says "The BUMPERS must be fixed to the BUMPER PERIMETER."

[dlavery]

Originally Posted by MikeDubreuil

My Dissent:
As a general rule of thumb- the GDC should not provide a figure as an example for a rule that violates other rules in the manual. This definitely creates confusion. The other part of the figure 8-2 which creates confusion is corners E and F. These two corners apparently are not corners and are in fact "curves." From the Q/A response, the GDC will not define a curve.

From that my friends, I may make without hesitation and purely for intellectual and kindly debate that I make this claim: In the Scott Hill Image corners A and B are not corners and are in fact "curves" making this configuration LEGAL.

<sigh> The Q&A forum has made this statement over and over and over again:

Figure 8-2 is solely intended to illustrate the legality of some ways in which BUMPERS could be arranged on the four indicated exterior corners (marked "OK" or "Not OK"). This is to provide insight into one particular clause of one rule. It is not intended to provide a complete example of every Robot Rule. Please do not infer any other conclusions from that example (e.g. the location of the Trailer Hitch is intentionally not shown in Figure 8-2; please do not make any assumptions about the legality/illegality of the Trailer Hitch location based on this illustration).

DO NOT READ MORE INTO THE ILLUSTRATION THAN IS SUPPORTED BY THE TEXT OF THE RULE. I don't know how that can be stated more clearly. To state that every illustration must be in complete compliance with every rule in the manual is possibly one of the most unrealistic notions ever. EVERY illustration is based on the reasonable expectation that the audience will apply a modicum of thought to understanding the illustration, and use the available context (established by the referencing text) to identify and extract the useful information supplied. There is NEVER an expectation that an illustration be anything more than an abstraction of a particular subset of all available information, included as a clarifying aide regarding a particular point.

For example, why is it that you are just focused on the presence/absence of bumper segments across the lower edge of the robot in the 8-2 illustration ("lower" in the reference frame of the illustration)? If anyone were really on their game, they would also note that upon immediate inspection the robot is also in violation of Rule <R06>, <R10>, <R11>, <R14>, <R15>, <R18>, <R19>, <R20>, <R21>, <R23>, all of the fabrication schedule rules, <R29>, <R32>, <R33>, every one of the power distribution rules (<R38> through <R49>), <R55>, <R56>, <R57>, <R58>, <R59>, <R62>, <R64>, all of the operator console rules (<R79> through <R88>), <R90>, <R91>, <R93>, and probably several other rules. The illustrated robot is also a two-dimensional figure. Two dimensional robots are not allowed in the competition (implicit effects of Rule <R55>, <R58> and <R64> wherein three-dimensional devices must be included as part of the robot). Since it is in violation of Rule <R18> it cannot haul a trailer, thus it cannot participate as a viable entry into the game. So it is in clear violation of both the letter of the rules and the intent of the game. Yet no one seems to have a problem with that.

At this point, if you have any common sense at all, you are saying "that is silly, of course the illustration of the robot in figure 8-2 doesn't need a control system included. That is not relevant to the text referencing the illustration, and it would be unnecessary - even distracting - to include all that extra information."

That is exactly the point. Neither the illustration nor the text referencing the illustration are saying anything about anything other than the four corners indicted with "OK" or "not OK." Don't assume that there is any more implied information content than that.

[Cory]

Originally Posted by Scott Hill

Abwehr,
The GDC has clearly and repeatedly stated, through the Q&A, "both sides of the corner must be protected by bumper segments". And they have stated "bumper segments must be a minimum of 6". I don't believe they have ever stated ..."all bumper perimeter corners must be protected on both sides by a bumper segment of at least 6." The statements do not mean the same thing. Also, this condition is significantly different from the concave corners discussion. I agree with you that the rules are the rules, we all just need to understand them. Go to the "is this corner considered protected" thread for a more in depth discussion.

Thanks,
scott

Scott,

I'm not sure what's unclear about "bumper segments". Segments is plural. That implies two bumper segments, which means both sides of the corner.

Originally Posted by Matt C

I'm sure they would get a useful answer if they provided the illustration to the GDC that they provided to us.

The odds of that are just about zero. The GDC has stated that they will not comment on the legality of specific designs.

[Molten]

Hill:
Ok, here's a thought. Listen to lavery. Ask the Q&A and listen to their response. I've read your posts on the Q&A and must say that they answered your question. Their answer was that it is up to the ref. Now, this means: Go ahead with the design and test your luck with the refs, or use a design that you are already 100% certain is completely allowed. How was their response not clear? They answered the question the only way they can.

[Aren_Hill]

Dave, for a discussion of figure 8-2 involving a Q and A answer see:
http://www.chiefdelphi.com/forums/sh...4&postcount=11

We're trying to take the discussion away from figure 8-2 and judge this configuration based on the original competition manual rules and pertinant team updates and Q and A responses.

Russ stated a simple way all of this could have been avoided and possibly yet be mitigated prior to competition.

We and we think many others would appreciate a Team Update that clarifies this.