pic: Robot Bumpers

[dlavery]

Originally Posted by MikeDubreuil

<edit> Do you think the GDC and FIRST actually expect every team to read every Q/A response to be sure they are in compliance with a new rule? </edit>

Yes, actually, they do. That is why the Q&A system is explicitly called out in the "Communications" Section of the Manual (Section 1.6), and highlighted as one of the important responsibilities of the team "Game Rules Monitor" position on the team (described in Section 2.6 of the Manual).

Originally Posted by MikeDubreuil

We're on the 6th revision of the robot manual if "corners must be protected on both sides" was actually a rule the GDC would put it into the competition manual.

It is already there, and has always been there since the Manual was released. So no change to the rule is necessary.

If you don't understand what the rule means, then ask a question in the official Q&A system and have the rule explained. Nothing here is official, and in the context of the competition, nothing discussed here matters. Submit it as a formal question to the Q&A system and get an official determination on the question. I am sure that the folks that answer the Q&A questions will be happy to respond with exactly the same answer that has already been provided multiple times, and let you know that the illustrated bumper configuration will not pass inspection.


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[MrForbes]

Apparently the GDC feels it's obvious that

R08-I. BUMPERS must protect all exterior corners of the BUMPER PERIMETER (see Figure 8 - 2).

means that there must be bumpers on both sides of every corner of the bumper perimeter, even though the referenced figure shows otherwise, by having unprotected corners on either side of the trailer hitch.

Unfortunately, the folks designing and building robots don't all see it as obvious.

What to do?

[Elgin Clock]

Originally Posted by squirrel

What to do?

Avoid a week one regional this year at ALL costs until examples of robots are passed through inspection & we can see what inspectors & the GDC really meant as far as "outside the box" designs that aren't rolling rectangles!

I hate to sound harsh, but apparently there are a lot of loopholes in this rule that the GDC & teams do not see as cut & dry.

Week one will be interesting to say the least.
(Even moreso with bumpers... let alone problems undoubtedly associated with the new control system.)


And a note to teams. Be nice to your inspectors. This year especially!

[Russ Beavis]

It's becoming obvious that I need to officially release the inspector training materials ASAP. The new materials will include a set of "good"/"bad" diagrams that should, I hope, ensure regional-to-regional inspection consistency. Please check the website with the FIRST manuals often for the inspection materials (I'm sure that a Team Update will probably indicate when the docs are available as well).

After you read the inspection materials, do NOT be surprised if your robot inspector deems the above bumper configuration to be ILLEGAL. The Section 8 Robot Rules and various GDC Q&A responses have always required 6" bumper segments on both sides of every "exterior corner". The diagram at the top of this thread does not have the required 6" segments at every corner ("corner" being EVERY vertex in the Bumper Perimeter).

From my perspective, I think that R08 would be more painfully clear if the word "exterior" were removed from "exterior corners" and figures 8-2 and 8-3 were updated to either officially declare the unlabeled features to be "NOT OK" or fix them so that they are "OK".

Russ Beavis
Chief Inspector

[Russ Beavis]

I'd also recommend that the wording of Robot Rule R08-i be modified with wording from related Q&A responses to say something like "BUMPERS must protect all corners of the BUMPER PERIMETER with BUMPERS on both adjoining perimeter segments".

More clear? "Protect" isn't very easy to quantify but it's obvious (at least to me) that the GDC Q&A responses are requiring 6"+ bumpers on both sides that meet in a "corner".

Russ

[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 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.

[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.

[Matt C]

Originally Posted by MikeDubreuil

In the Scott Hill Image corners A and B are not corners and are in fact "curves" making this configuration LEGAL.

I believe that if it looks like a corner, acts as a corner, and feels like a corner, it's a corner.

If the point of tangency (of the change in direction) can't easily/quickly be identified, it's probably a curve.

I personally think A and B in the picture are to be considered corners, thus not being a legal configuration.
If they had a much broader radius (lets say >8 in.), I'd start to consider them more a curve than a corner.

[Jared Russell]

In my mind, a legal curve's minimum radius is functionally defined by your ability to bend a solid piece of 3/4" plywood around it without causing your bumper to break any rules (e.g. it must be backed all the way around by frame and remain rigid and strong).

This limit arguably excludes an even larger class of curves than the "I know a curve when I see it" test...

[dlavery]

Originally Posted by Abwehr

In my mind, a legal curve's minimum radius is functionally defined by your ability to bend a solid piece of 3/4" plywood around it without causing your bumper to break any rules (e.g. it must be backed all the way around by frame and remain rigid and strong).

This limit arguably excludes an even larger class of curves than the "I know a curve when I see it" test...

And how is that test applied when you steam the piece of plywood and bend it around a 1/4-inch radius? (yes, it can be done)

You see, the arguments are not as simple as they might first appear.


-dave



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[Gdeaver]

This thread is an_l retentive. Get on with it. Week 4 is half shot. There have got to be other issues with the robot than your robot's rear end. Square it up and move on. The design does not allow picking up from the floor so you got 7 balls to make count. The drivers need allot of practice to make each one of them count. Our team learned from aim high that the human loading of balls requires great skill. With the strategy you have chosen practice and perfection are more important than the robots but. Let this thread die.

[Dr Theta]

Here's a purely hypothetical situation. Let's say that a team designs a chassis in which there are no sharp angles, only rounded ones so their bot isn't actually a polygon, nor does it actually have any corners... Say using a bent-pipe frame rather than straight-pipe? Just curious.

[Aren_Hill]

this debate effects other robot orientations than just the one being shown, so it should kinda be resolved before the regionals begin, so dont let the thread die please. This also is not talking specifically about the robot mentioned in the other thread.