pic: Robot Bumpers

[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.

[Dr Theta]

I have to agree that this is a vital issue, I would hate to see teams disqualified over this rule. I believe that this orientation is Illegal as stated within the manual in which clearly states Compliance with all rules is mandatory this orientation is not in compliance with all rules and is therefore illegal.

[dlavery]

Originally Posted by 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.

Hopefully, there are NO teams that are allowing this discussion to influence the design of their robots. If any team still has serious questions about how the rules are interpreted and/or applied, they should be going to the official FRC Q&A forums to get those questions answered. To remind everyone once again, NONE of the discussions here - no matter who the source may be - are official answers. Nothing said here will carry any weight with the inspectors or competition officials. "I got the answer on CD" does not work when trying to explain why your 167 pound robot should be allowed to compete (yes, this has happened ).

Related to that, the various responses in the Q&A forums have made it pretty clear that reviews of specific designs will not be provided. But you can expect direct questions about how a rule will be applied to be answered. So when posing your question, instead of asking "here is a picture of my design - tell me if my corner bumpers are legal," you might ask "Given rule <R08-A> and <R08-I>, does this mean that a bumper segment of at least six inches in length is required on each side of an exterior corner of the robot?" I am pretty sure that the second form of the question will be answered (actually, I am pretty sure that it has already been answered multiple times, but some here obviously remain unconvinced).

-dave


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[Madison]

Originally Posted by dlavery

Related to that, the various responses in the Q&A forums have made it pretty clear that reviews of specific designs will not be provided. But you can expect direct questions about how a rule will be applied to be answered. So when posing your question, instead of asking "here is a picture of my design - tell me if my corner bumpers are legal," you might ask "Given rule <R08-A> and <R08-I>, does this mean that a bumper segment of at least six inches in length is required on each side of an exterior corner of the robot?" I am pretty sure that the second form of the question will be answered (actually, I am pretty sure that it has already been answered multiple times, but some here obviously remain unconvinced).

-dave


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Perhaps we might ask instead if "a bumper segment of at least six inches in length is required on each side of EVERY exterior corner of the robot?"

An answer to that ought to quickly affirm whether or not the bumper arrangement surrounding A and B is legal. Or, maybe not.

[Luis28]

how far should the trailer hitch be away from the bumpers.

[EricH]

Originally Posted by Luis28

how far should the trailer hitch be away from the bumpers.

Far enough to not hit the trailer tongue on the bumpers before the trailer bumpers hit your bumpers (<R18-E>). Any more specific answer will depend on your specific design.