pic: Is this corner considered protected?

[Mike8519]

I will also have to say that this configuration is illegal due to the requirement of both sides requiring protection and that protection required to be 6" long BUMPERS.

[Al Skierkiewicz]

Scott,
In looking at the picture and visualizing certain field elements, I think it is entirely possible for an unprotected/non bumper portion of the robot to contact a field element or another robot. Certainly, the angle of the trailer tongue shown in the photo would allow a wide variety of possiblities, my robot included. In my mind, the rule that states in part...
R08 The BUMPER location and design have been specified so that ROBOTS will make BUMPER-to-BUMPER contact during any collisions. If implemented as intended, a ROBOT that is driven into a vertical wall in any normal PLAYING CONFIGURATION will always have the BUMPER be the first thing to contact the wall.
I would be hard pressed, from this photo, to be able to prove to myself that your robot design would be able to meet this specification.

[Kyler]

curiously enough, the GDC never actually says in http://forums.usfirst.org/showthread.php?t=11600 that the configuration is illegal, only that figure 8-2 is meant to be an example. Just to point that out.

[dlavery]

Originally Posted by Kyler

curiously enough, the GDC never actually says in http://forums.usfirst.org/showthread.php?t=11600 that the configuration is illegal, only that figure 8-2 is meant to be an example. Just to point that out.

The question in that Q&A post never asked if the configuration on their robot was illegal or not. So of course they did not get a determination of the legality of the configuration.


.

[Joe Ross]

Originally Posted by dlavery

The question in that Q&A post never asked if the configuration on their robot was illegal or not. So of course they did not get a determination of the legality of the configuration.

Had they asked about that specific robot, they would have been referred to team update 6 and still not get the answer they wanted.

[5n1p3r]

technically you only need to cover 3 sides lol, im jk but really i would consider this well over the range of legal. The trailer aint bumpin so it seems perfectly fine lol

[Mike8519]

Originally Posted by 5n1p3r

technically you only need to cover 3 sides lol, im jk but really i would consider this well over the range of legal. The trailer aint bumpin so it seems perfectly fine lol

But the rear corner is not protected on both sides

[Mike Martus]

As a Lead Inspector in many Michigan Events I can see a headache in the making. I hope many of the bumper issues stated here are not typical.... bottom line is.... the rules rule!

[Scott Hill]

the drawing shows a ROBOT BUMPER PERIMETER with BUMPERS (blue) and corner fillers (red) which I think reasonably represents the ROBOT and CORNER in question.

The BUMPER PERIMETER is a polygon. The polygon has 6 corners; A,B,C,D,E,F. 2 of the corners, D,E, have right angles. 4 of the corners, A,B,C,F, have obtuse oblique angles. The polygon has 6 sides; AB,BC,CD,DE,EF,FA.

The corner in question with respect to this thread is corner A. There are 2 sides "of corner A", side AB and side FA.

Each side of the corner, side AB and side FA, is protected by BUMPERS. Each sides protection clearly meets the intent of <R08> ..."If implemented as intended, a ROBOT that is driven into a vertical wall in any normal PLAYING CONFIGURATION will always have the BUMPER be the first thing to contact the wall."... . Side AB has no BUMPERS on it yet the BUMPER configuration clearly meets the intent of the rule, which is clearly stated.

EricH, I enjoy reading your may posts in these fora. I think you do a lot to contribute positively with your comments. However I must take issue with your position on this question. What I believe are the relative sentences from your referenced sources follow, with my comments appended:

Reference #1: "Both sides of the corner must be protected." Comment: they are, see above.

Reference #2: "Both sides of the corner must be protected by BUMPER segments." Comment: they are, see above. "Rule <R08-i> requires BUMPER protection on every corner of the BUMPER PERIMETER." There is obviously BUMPER protection on every corner of the BUMPER PERIMETER, see above drawing.

Reference #3: This reference is not on point because the answer is given with respect to a rectangular ROBOT BUMPER PERIMETER, not the BUMPER PERIMETER in question.

Reference #4: "The interpretation that "both sides of an exterior corner must be protected with segments of bumpers, and the bumper segments must be a minimum of 6 inches" is correct." Comment: both sides of the corner are protected, see above, and the bumper segments in the example can be easily made to meet the 6" minimum dimension requirement.

Mike8519: You state ..."those corners must be protected by 6" of bumper on each side"..... I think if you read carefully the requirements typically state ..."both sides of the corner must be protected"... not, corners must be protected on each side. They do not mean the same thing.

Thanks to all for contributing to the discussion,

Scott

[EricH]

Originally Posted by Scott Hill

[edited for brevity]

Reference #2: "Both sides of the corner must be protected by BUMPER segments." Comment: they are, see above. "Rule <R08-i> requires BUMPER protection on every corner of the BUMPER PERIMETER." There is obviously BUMPER protection on every corner of the BUMPER PERIMETER, see above drawing.

Please note the plural form. The GDC has been quite clear on this. There is bumper protection, yes. It is protected by a bumper segment. I'm nit-picking here, but it seems that this would be illegal.

Reference #4: "The interpretation that "both sides of an exterior corner must be protected with segments of bumpers, and the bumper segments must be a minimum of 6 inches" is correct." Comment: both sides of the corner are protected, see above, and the bumper segments in the example can be easily made to meet the 6" minimum dimension requirement.

Again, plural form is used.

Mike8519: You state ..."those corners must be protected by 6" of bumper on each side"..... I think if you read carefully the requirements typically state ..."both sides of the corner must be protected"... not, corners must be protected on each side. They do not mean the same thing.

While the words don't mean the same thing, the first is a subcase of the second. The first is also what the GDC seems to be saying.

I know how we can settle this once and for all. Submit the picture to Q&A. Ask: "Are corners A and B adequately protected under <R08>? If not, why not?" If they don't refer you back to the rule, they will hopefully give a straight answer.

The other option is that they say, "we cannot comment on specific robot designs", in which case I would advise having a more conservative route available at the event or just plain installed on the robot.

[Scott Hill]

EricH,

Thanks for your comments.

Question: If the plural is required as you say and "protected by a bumper segment" would not be legal, as you suggest, is a robot side legally protected if it is covered completely by only one bumper segment?

I think it would be.

I also don't see how you can consider the first of the two statements as you list them as a subcase of the second. I have never seen the GDC say the first, and I have quite often seen them specifically say the second.

Scott

[EricH]

Originally Posted by Scott Hill

EricH,

Thanks for your comments.

Question: If the plural is required as you say and "protected by a bumper segment" would not be legal, as you suggest, is a robot side legally protected if it is covered completely by only one bumper segment?

I think it would be.

We aren't considering sides, are we? We are considering corners, which are a junction of two sides.

I also don't see how you can consider the first of the two statements as you list them as a subcase of the second. I have never seen the GDC say the first, and I have quite often seen them specifically say the second.

Scott

On this, I have reviewed. If the corners must be protected on by six inches of bumpers on both sides, then by definition, both sides are protected. So the second is a subcase of the first, but may also stand alone. I stand corrected.

However, I now have some more things to consider. Several teams have recently asked, "will bending 1 6+" bumper segment around a corner be legal if we don't have backing in the corner and we have less than 6" on one side?" or something to that effect. The GDC has answered no to all cases like this. But if you had a 13" piece of bumper, broken into 2 6" segments and a filled, I'm pretty sure that would be legal. Just some food for thought.

[Scott Hill]

EricH,

I believe the statements you included were referencing the sides of the corner.

Thanks,

Scott

[Tristan Lall]

Originally Posted by Scott Hill

Each side of the corner, side AB and side FA, is protected by BUMPERS. Each sides protection clearly meets the intent of <R08> ..."If implemented as intended, a ROBOT that is driven into a vertical wall in any normal PLAYING CONFIGURATION will always have the BUMPER be the first thing to contact the wall."... . Side AB has no BUMPERS on it yet the BUMPER configuration clearly meets the intent of the rule, which is clearly stated.

It looks like you're suggesting that any bumper design that satisfies the condition in the intent statement offers the required protection. That's not unreasonable, but I don't think that's the way that the GDC understands it.

As a test case for your theory, consider a robot similar to the one you posted above. Move the trailer hitch out of the way (put it in the gap on DE). Delete the section AB. Extend the segments FA and BC to their intersection, and call it G (but leave the bumpers as-is). Delete points A and B, leaving us with rigid segments GC and FG. Now, if we perform those operations on the picture above, we end up with a big sharp corner (at G) that clearly extends beyond the bumpers. This contravenes the condition in the intent statement, and is not protected by segments. But what if we made the angle at G something large, like 170°? There is still a corner (a discontinuity in the radius of curvature), but now the thickness of the existing bumpers allows it to pass the intent statement's condition (the corner doesn't stick out past the outermost edges of the bumpers anymore).

Is it your contention that even though the 170° corner at G is not abutted by any bumper segments, all necessary conditions are met (because the bumper hits first), and it would therefore be legal? If that's the case, then the amount of protrusion (inward or outward) past the edge of the bumpers is the most critical factor in determining protection (under your theory).

Apparently, the GDC considers the condition in the intent statement and the corner protection requirement to be separate, necessary conditions. Furthermore, it looks like they understand corner protection to mean a design with a legal bumper segment on each side of the corner.

Assuming that the function of the Q&A is to guide the interpretation of rules, but not to impose additional constraints*—that being the function of the rules and updates—the GDC's responses regarding corners have been mutually consistent and legal under the rules—so following them precisely ought to be acceptable at any event. (That's your best course of action.)

There might be some room for your interpretation, however: the GDC is describing a legal way to meet an existing requirement (protection of corners per <R08>, part I), but there's nothing in a rule or update that says that this is the only possible way to protect a robot's corners—in fact, to say that there is only one legal mode of protection (without some sort of explicit definition in the rules) is a bit of a stretch of the principle that the Q&A shouldn't be defining new constraints. (Yet, I think that that's implied here.) So as I understand it, you're relying on the fact that the next best thing to a direct definition of protection is the intent statement, and that because your proposed design passes that test, your corners are protected.

Like I said, it's not unreasonable...but you're taking a big risk that the inspectors at any given event will be open to considering that logic, and will arrive at the same conclusion as you, and that FIRST won't clarify things once and for all in an update (ruling against you).

*FIRST has not stated this directly for a couple of years, but that was formerly the rule of precedence. Maybe they made the statements in the 2009 Q&A binding, but neglected to tell anybody....

[waialua359]

Originally Posted by Mike Martus

As a Lead Inspector in many Michigan Events I can see a headache in the making. I hope many of the bumper issues stated here are not typical.... bottom line is.... the rules rule!

I agree with this one. There will be many headaches for inspectors and some very unhappy campers on both sides.

The most simplest solution, while it may not allow teams to be as creative as they wanted to be, is to have a frame, that is unquestionably, legal.

From past experience the last several years, I dont want those headaches again as much as possible.