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EricH 31-01-2014 22:35

Re: Non-level bumpers
 
Quote:

Originally Posted by Jared (Post 1335584)
In 2013, since there was nothing in the rules about angled bumpers, we showed our inspector at CMP the Q and A answer. He brought it to the LRI, who said that the rules permitted our bumpers (and the bumpers of 1114 and 67).
Or, if magnets is right, and the meaning of the sentence has changed because they are now providing an interpretation of this sentence instead of just giving us a vague sentence, this means that the correct interpretation for this year (not legal) contradicts what they wanted teams to get out of it last year (angled bumpers are legal), which again, doesn't make too much sense.

I think they should address this in a team update.

Or... the LRI made a mistake. Key volunteers do occasionally make a mistake--they're human, after all.

I agree--this needs to be either a team update, or a "better" Q&A. That said, I would advise any team considering angled bumpers to have a backup plan in case Q&A continues to disallow and no update addresses the issue. (BTW, I'm still waiting for someone to follow up on the "wheels are frame perimeter if they stick out from the frame" ambiguity.)

magnets 31-01-2014 22:38

Re: Non-level bumpers
 
Quote:

Originally Posted by EricH (Post 1335602)
Or... the LRI made a mistake. Key volunteers do occasionally make a mistake--they're human, after all.

I agree--this needs to be either a team update, or a "better" Q&A. That said, I would advise any team considering angled bumpers to have a backup plan in case Q&A continues to disallow and no update addresses the issue. (BTW, I'm still waiting for someone to follow up on the "wheels are frame perimeter if they stick out from the frame" ambiguity.)

Before the championship, the LRI/all the inspectors have a conference call with FIRST, and they go over what's legal and not legal. That's how the robot inspectors knew that 118 was illegal in 2012. With the three robots (1114, 67, and 236), I'd be willing to bet the GDC must have seen a picture of one of them at least, and if the bumpers were illegal, they'd let the CMP/Michigan championship inspectors know they were no good.

EricH 31-01-2014 23:24

Re: Non-level bumpers
 
Quote:

Originally Posted by magnets (Post 1335603)
Before the championship, the LRI/all the inspectors have a conference call with FIRST, and they go over what's legal and not legal. That's how the robot inspectors knew that 118 was illegal in 2012. With the three robots (1114, 67, and 236), I'd be willing to bet the GDC must have seen a picture of one of them at least, and if the bumpers were illegal, they'd let the CMP/Michigan championship inspectors know they were no good.

And there still could have been a mistake made. Trust me. I've seen a situation where someone who should have been on all the conference calls and been at all the trainings and all that made a mistake--and just about everybody knew it was a mistake, except this one person--and it was pretty blatantly obvious from the Manual that it was a mistake. The mess created by the aftermath of that one resulted in three extra teams at Champs that year from that event. Stuff happens.

Besides the fact that the GDC does not rule on specific designs, only provides input to the people that do make those rulings when asked...


Either way, I think this needs clarification. I don't have Q&A access as anything more than an observer; anybody who does want to ask? Q268, I see as angled with respect to "we want our bumpers to slant towards the robot"; Q199 (the first part) appears to be "we would like our bumpers to go from 10" down to 7, is this legal" or some equivalent, and thus addressed by the blue box. That's the one to follow up on--but don't bring 2013 into it, because that'll simply get a "last year's rules have no effect on this year" response from the GDC and we'll get no other clarification.

FrankJ 31-01-2014 23:48

Re: Non-level bumpers
 
Fig 4-8 shows the bumpers being perpendicular to the floor. You really can't tell if they are parallel from the figure despite what the blue box says. I have always interpreted that rule to mean you cannot have "cow catcher" bumpers. We have never had a reason to mount one end of bumper lower than the other or have anything other than rectangular bumper so we never tested the exact meaning.

Currently you can have several bumper segments on on a side each one slightly higher. having the net effect of an angled bumper. Now as dX approaches 0....

magnets 05-02-2014 08:03

Re: Non-level bumpers
 
Well, I thought I'd bring this back. Our team would really like angled bumpers (not like a cow catcher, but like 1114/67 in 2013), and we've been having quite an argument about the interpretation of the rule, and we were wondering what you guys thought.

There are currently three interpretations.

1.) The question and answer interprets the the blue box as saying no, so this year, the sentence in the blue box means the opposite as what it did last year, and angled bumpers are no good.

2.) The question and answer says that the blue box says no, and that sentence (which is a little ambiguous), means no, and 1114, 67, and 236 were all really illegal in 2013, but since the GDC never gave a clear response that year, no inspector could call them on it. (this is what I think)

3.) The q and a and game manual are in contradiction of each other.

Now, we may try some bumpers where the distance of each parallel segment is about 0.5" to get the same effect as angled bumpers.

If the GDC had put a rule in the original manual "bumpers must be parallel", then we wouldn't have had our sponsor waterjet an intake plate that only works with an angled bumper, or build a frame with an angled bumper, or build angled bumpers, or waste hours correcting the mistake. [/rant on bumper rules]

kmusa 05-02-2014 08:24

Re: Non-level bumpers
 
Quote:

Originally Posted by magnets (Post 1335568)
... Can the GDC get any more unclear?

Here's hoping that the GDC doesn't take this on as a challenge. ;)

-Karlis

Al Skierkiewicz 05-02-2014 09:08

Re: Non-level bumpers
 
WOW! Let me explain all of this for you guys.
1. Angled means strictly the horizontal orientation as described by the lower edge of the bumper system. If the bottom of the bumper is higher at one end than the other the Q&A has responded it is illegal this year to date(as of Feb 5, 2014).
2. Bumpers must be completely vertical because they mount on the FRAME PERIMETER which is series of vertical planes described by the outer dimensions of the robot. So that means no plows, no angles that help you pick up the ball, no wedges.
3. The Q&A contains answers to specific questions as answered by the GDC and other individuals. When these answers seem to contradict the rules, they become the rule and should be followed up with a Team Update to insure the maximum number of teams/team members are alerted to the change.
4. Horizontally angled bumpers were allowed last year as long as the entire bumper system remained in the 2" to 10" above the floor dimension. This allowed different bumper sections to be mounted at different heights around the perimeter of the robot.
5. The Blue Box in R22 was added this year. That is the reference made in the 2014 Q&A you are discussing.
6. Inspectors will inspect as directed by the rules or the Q&A whichever is most recent. We are after all, an extension of the GDC and are expected to perform as such to keep inspections consistent across the world.
7. Please remember that some of the rules are written to give you a challenge that you would not normally have. This make the contest more interesting and challenging. It is the way this competition has operated from the very beginning.
8. Yes, we do make mistakes from time to time, even me. I hope when I do make an error it is in your favor.

magnets 05-02-2014 11:43

Re: Non-level bumpers
 
Quote:

Originally Posted by Al Skierkiewicz (Post 1337901)
WOW! Let me explain all of this for you guys.
1. Angled means strictly the horizontal orientation as described by the lower edge of the bumper system. If the bottom of the bumper is higher at one end than the other the Q&A has responded it is illegal this year to date(as of Feb 5, 2014).
2. Bumpers must be completely vertical because they mount on the FRAME PERIMETER which is series of vertical planes described by the outer dimensions of the robot. So that means no plows, no angles that help you pick up the ball, no wedges.
3. The Q&A contains answers to specific questions as answered by the GDC and other individuals. When these answers seem to contradict the rules, they become the rule and should be followed up with a Team Update to insure the maximum number of teams/team members are alerted to the change.
4. Horizontally angled bumpers were allowed last year as long as the entire bumper system remained in the 2" to 10" above the floor dimension. This allowed different bumper sections to be mounted at different heights around the perimeter of the robot.
5. The Blue Box in R22 was added this year. That is the reference made in the 2014 Q&A you are discussing.
6. Inspectors will inspect as directed by the rules or the Q&A whichever is most recent. We are after all, an extension of the GDC and are expected to perform as such to keep inspections consistent across the world.
7. Please remember that some of the rules are written to give you a challenge that you would not normally have. This make the contest more interesting and challenging. It is the way this competition has operated from the very beginning.
8. Yes, we do make mistakes from time to time, even me. I hope when I do make an error it is in your favor.

Thanks for the clarification, but it's still not clear and really does need to be in a team update.

You stated that angled bumpers are legal in 2013. Go check the 2013 question and answer and look at question 42. They use the exact same sentence as what's in the blue box in the 2014 manual to allow angled bumpers for 2013. Now, this year, the same sentence is used again, but this time to disallow angled bumpers. So either angled bumpers weren't allowed in either 2013 or 2014, or angled bumpers were allowed in 2013, but not 2014, and the manual/q and a contradict each other.

Or, the definition of the words "overtly deviate" has changed.

Jon Stratis 05-02-2014 11:55

Re: Non-level bumpers
 
Quote:

Originally Posted by magnets (Post 1337957)
Thanks for the clarification, but it's still not clear and really does need to be in a team update.

You stated that angled bumpers are legal in 2013. Go check the 2013 question and answer and look at question 42. They use the exact same sentence as what's in the blue box in the 2014 manual to allow angled bumpers for 2013. Now, this year, the same sentence is used again, but this time to disallow angled bumpers. So either angled bumpers weren't allowed in either 2013 or 2014, or angled bumpers were allowed in 2013, but not 2014, and the manual/q and a contradict each other.

Or, the definition of the words "overtly deviate" has changed.

What part of Q199 is not clear?

Quote:

Q: If we construct the bumper as per the rules, can we angle the bumper so that one end is higher than the other?
A: No. Please see the Blue Box below R22.
I didn't know the meaning of the word "No" needed clarification.

Abhishek R 05-02-2014 12:13

Re: Non-level bumpers
 
Quote:

Originally Posted by Jon Stratis (Post 1337963)
What part of Q199 is not clear?



I didn't know the meaning of the word "No" needed clarification.

Right, so the answer is no. Maybe the reference is unclear when you compare it to 2013, but that's in the past so it doesn't matter.

magnets 05-02-2014 12:15

Re: Non-level bumpers
 
Quote:

Originally Posted by Jon Stratis (Post 1337963)
What part of Q199 is not clear?



I didn't know the meaning of the word "No" needed clarification.

The No part is very clear. I understand very well that we are not allowed to use angled bumpers. The same sentence used this year to disallow angled bumpers was used last year to allow angled bumpers, which is the bad part.

Most teams don't read every single q and a response. When they see the blue box below r22 that has the sentence used to allow angled bumpers in 2013 (in q42 of the 2013 q and a), they will assume that angled bumpers will be allowed again. However, the meaning of the words "overtly deviate" has changed, and it would be nice to let teams know that this definition has changed so that they can design around the new meaning, as opposed to the 2013 version.

I'm not trying to contest the fact that the definition of a very, very vague sentence has changed from one year to another. r22's blue box is pretty ambiguous, and the q and a clarifies it. I just really feel that it's not going to be clear to a team who reads the manual, but not every q and a response. But I guess that's their problem, just like it was our problem that we didn't ask a q and a, and assumed the 2013 interpretation would stay.

Steven Donow 05-02-2014 12:20

Re: Non-level bumpers
 
Quote:

Originally Posted by magnets (Post 1337972)
The No part is very clear. I understand very well that we are not allowed to use angled bumpers. The same sentence used this year to disallow angled bumpers was used last year to allow angled bumpers, which is the bad part.

Most teams don't read every single q and a response. When they see the blue box below r22 that has the sentence used to allow angled bumpers in 2013 (in q42 of the 2013 q and a), they will assume that angled bumpers will be allowed again. However, the meaning of the words "overtly deviate" has changed, and it would be nice to let teams know that this definition has changed so that they can design around the new meaning, as opposed to the 2013 version.

I'm not trying to contest the fact that the definition of a very, very vague sentence has changed from one year to another. r22's blue box is pretty ambiguous, and the q and a clarifies it. I just really feel that it's not going to be clear to a team who reads the manual, but not every q and a response. But I guess that's their problem, just like it was our problem that we didn't ask a q and a, and assumed the 2013 interpretation would stay.

Then isn't it that team's fault for not reading the Q&A for clarification on (what you see as) an ambiguous subject?

magnets 05-02-2014 12:26

Re: Non-level bumpers
 
Quote:

Originally Posted by DevenStonow (Post 1337979)
Then isn't it that team's fault for not reading the Q&A for clarification on (what you see as) an ambiguous subject?

Sure, but (I hope) the point of the q and a and updates isn't to confuse teams and make it harder for them to pass inspection (though historically, it seems that this may be true).

When the GDC changes the definition of words in the manual, it would be really nice to see them outlined in an update(of the first draft of the manual). Would you be happy if you turned up to your competition and discovered that the type of tread used on your wheel was suddenly considered a traction device and was illegal? If nobody had asked the bumper question, then teams would have shown up to competition with angled bumpers, and would have been unable to use their intake mechanism that relied on angled bumpers.

Joe Ross 05-02-2014 12:34

Re: Non-level bumpers
 
Now you understand 118's pain in 2012. Their solution was legal using the definition of Grapple from 2011, and there were no changes to the rule in 2012, and yet their robot was ruled illegal.

Quote:

Originally Posted by magnets (Post 1335603)
Before the championship, the LRI/all the inspectors have a conference call with FIRST, and they go over what's legal and not legal. That's how the robot inspectors knew that 118 was illegal in 2012. With the three robots (1114, 67, and 236), I'd be willing to bet the GDC must have seen a picture of one of them at least, and if the bumpers were illegal, they'd let the CMP/Michigan championship inspectors know they were no good.

118's robot passed inspection as it was not illegal from inspection standpoint. The Head Ref is the person who enforces the game rules and the definition of Grapple.

Al Skierkiewicz 05-02-2014 13:31

Re: Non-level bumpers
 
Magnets,
It is irrelevant at this point that the interpretation was different last year. It is this year's Q&A that has answered the question as it applies on Feb 5, 2014 to 2014 robots.


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