G13, G44 and Pinching Rollers

[jamie_1930]

In my opinion you're right in this case. Although on a different note, I'd prefer we not dwell on the past seeing that competition season is officially over.

[Eugene Fang]

We had a qualification match against 148 in Archimedes. We pushed them onto the bump so that they were obviously "carrying" the ball. There was a penalty that match but it wasn't because of that. Just wanted to share.

[Cory]

I'm obviously not an impartial source but I was field side directly in front of 33 when they got called for one of those carrying penalties. They were not being interacted with by another robot and were not against a bump. I saw the ref signal it and I saw the ball come up off the ground a bit. It wasn't very blatant, it's not like it was 2" off the ground-but you could see it come up.

That said, it wouldn't surprise me if the same thing had occurred to us at some point as well and it got missed or was given a pass. Our roller system is designed so it's nearly physically impossible for this to happen, but sometimes weird stuff occurs.

It seemed like for the most part the attitude of the referee crew on Archimedes was to let the teams play unless there was a very clear violation. Overall I thought it was the best reffing I had seen at any event I've been to this year, and maybe over the last two years.

[TEE]

Originally Posted by Cory

I'm obviously not an impartial source but I was field side directly in front of 33 when they got called for one of those carrying penalties. They were not being interacted with by another robot and were not against a bump. I saw the ref signal it and I saw the ball come up off the ground a bit. It wasn't very blatant, it's not like it was 2" off the ground-but you could see it come up.

If that's the case I apologize. I remembered a lot of jostling, and I remember the bumps being the cause of the ball-carrying, and I guess I inferred subconsciously that 33 got pushed up the ramp

and when I said I was disappointed in some referees, I was referring to earlier competitions. There was an instance where our hook missed (during the finale), and ended up hanging 5 or so inches outside of our bumpers, and the refs called a penalty. Afterwards, we pointed out that robot is allowed to expand to the finale configuration (eg. go outside bumpers) during the finale, the head referee said that you could only get wider in the space above the robot O.o we then showed him the rule, and he waived the penalty. I would understand if it were in the earlier competitions, but I believe this was during the Michigan State Competition.

@ Wayne: If it was obvious, I would assume not. That said, I wouldn't put someone who's easily pushed around in that precarious position
And if you're attempting to find a way to defeat 469, I would suggest looking into what 294 did... they were amazing. Somewhere in the thread below, the driver coach (I think) for 294 described their strategy.

http://www.chiefdelphi.com/forums/sh...595#post956595

[ChristopherSD]

If I read correctly, I think you're correct. I've recorded videos of every elimination round 201 was in, so I'll look those over sometime soon.

[JVN]

I thought the reffing was fantastic on Archimedes. I have no complaints about any of the calls in our run. We got beat in two very tough matches against an incredible alliance!

[ChristopherSD]

Originally Posted by JVN

I thought the reffing was fantastic on Archimedes. I have no complaints about any of the calls in our run. We got beat in two very tough matches against an incredible alliance!

The reffing was indeed excellent during the elimination rounds. They did scare me after that first match of the eliminations when we thought we had lost. I was relieved when they corrected it.

[Ether]

Originally Posted by jamie_1930

I'd prefer we not dwell on the past seeing that competition season is officially over.

"Dwell on the past" has a negative connotation that doesn't seem to reflect the tone of the original post.

Provided the discussion is civil, it is productive and useful to have such a dialog. Some good may come of it.


~

[jspatz1]

I see the use of pinching rollers this year as a high-risk, high-reward gamble for those that chose to employ them, and was sort of the elephant in the room all season. Some had the flexibility or verticle freedom to leave the ball in contact with the ground when the robot experienced small bumps or elevations. Some did not. If you chose to grip the ball, you were making a judgement that the benefits of doing so outweighed the risks of incurring penalties when your robot experienced motions that caused the ball to come out of contact with the carpet momentarily. For those that had no flexibility in their gripper, it was almost a given that at some moment in the match they would experience some motion that would cause them to technically carry the ball when bumped by another robot, when going over a small lip or bump (such as the lip in front of the bumps), when tilting slightly through their own movements, or when pushing a ball into a goal. The real question was whether the referees would catch these momentary lifts, or whether they would interpret them to be penalized lifts. In my opinion, incurring a penalty because another robot bumped you when you were gripping a ball is not the kind of situation that is being refered to in the "one robot cannot cause a penatly for another robot" rule. Significant contact between robots is expected and part of the game. If it was the nature of your gripper that such robot contact caused you to lift the ball, then that was a vulnerablility of your design and a risk you chose to take. In our case, we interpreted the carry rule as absolute, and chose to capture the ball against the carpet so that is was impossible to inadvertantly carry. But we recognize that a pinching roller was an effective and worthwhile tactic for those that did it well.

[Wayne TenBrink]

Originally Posted by jspatz1

In my opinion, incurring a penalty because another robot bumped you when you were gripping a ball is not the kind of situation that is being refered to in the "one robot cannot cause a penatly for another robot" rule. Significant contact between robots is expected and part of the game. If it was the nature of your gripper that such robot contact caused you to lift the ball, then that was a vulnerablility of your design and a risk you chose to take.

Pardon me for veering off the original topic, but I have a related question and comment.

The question: If a "red" robot was parked on top of the bump next to the "blue" home zone, would/should they be penalized if a red robot pushed them off the bump and into the blue zone, making them the 2nd red bot in the blue zone? Is that part of normal contact or is that forcing a penalty? (For example, if my alliance is playing against 469 at the MARC and we put a robot on the bump right next to them, would we get a red card if somebody pushed that bot off the bump?)

The comment: There has been a lot of discussion about robots that are inherently capable of violating rules which are difficult for the referees to judge (2010: 3" incursion, active mechanisms above the bumper, multiple ball possession, pinching roller; 2007/2008: envelope violations, etc.). In my opinion, unless a feature or capability is specifically forbidden by either the robot rules (inspector's call) or game rules (referee's call), teams have the right to risk penalty in exchange for enhanced capability - as long as there is a legitimate/legal use for that capability. However, I think these teams should expect that referees will rule against them in the case of a close call. (For example, a robot with a wide ball collector that is posessing one ball while it "herds" another with the same device does not deserve the benefit of the doubt.)

[jspatz1]

Originally Posted by Wayne TenBrink

In my opinion, unless a feature or capability is specifically forbidden by either the robot rules (inspector's call) or game rules (referee's call), teams have the right to risk penalty in exchange for enhanced capability - as long as there is a legitimate/legal use for that capability. However, I think these teams should expect that referees will rule against them in the case of a close call.

Absolutely right. Everyone has the right to push the envelope, that is what sometimes separates the good robots from the great. Any penalty-capable feature is a calculated risk. You can be sure there were many momentary lifts by pinch rollers this year that were not caught by referees. Judging how far you can push a rule is a design decision we face with almost every game. Just one aspect of predicting what the gameplay will really be like.

[Wayne TenBrink]

Originally Posted by jspatz1

Absolutely right. Everyone has the right to push the envelope, that is what sometimes separates the good robots from the great. Any penalty-capable feature is a calculated risk. You can be sure there were many momentary lifts by pinch rollers this year that were not caught by referees. Judging how far you can push a rule is a design decision we face with almost every game. Just one aspect of predicting what the gameplay will really be like.

I don't advocate pushing the rules in hopes of slipping something past the referees. I just wouldn't write off a good idea because it introduced he possibility of a penalty. Many pinching roller ball collectors didn't compensate for irregularities in the floor and "carried" balls for brief periods. I think they deserved to get called for carrying whenever they did it, and the referees didn't owe them the benefit of the doubt on a close call. Nevertheless, a functional ball collector that collects an occasional penalty is better than no ball collector at all. 469 may have gotten called for active mechanism above the bumper once or twice, but that doesn't mean their ball deflector switch was a liability. 1918's wide ball collector was physically capable possessing more than one ball at a time, but the ease of ball acquisition outweighed the risk of penalties and the occasional hassle of having to take evasive action.

[jspatz1]

Originally Posted by Wayne TenBrink

a functional ball collector that collects an occasional penalty is better than no ball collector at all. 469 may have gotten called for active mechanism above the bumper once or twice, but that doesn't mean their ball deflector switch was a liability. 1918's wide ball collector was physically capable possessing more than one ball at a time, but the ease of ball acquisition outweighed the risk of penalties and the occasional hassle of having to take evasive action.

Yes this is exactly what I meant by a calculated risk/reward. We also had and extra-wide ball magnet that could easily possess more than one ball, but its extreme effectiveness in easy acquisition made it more than worth the risk. I don't believe we ever recieved a multiple possession call, although I can't claim for sure that it never inadvertently happened.

[Joe Ross]

Originally Posted by Wayne TenBrink

The question: If a "red" robot was parked on top of the bump next to the "blue" home zone, would/should they be penalized if a red robot pushed them off the bump and into the blue zone, making them the 2nd red bot in the blue zone? Is that part of normal contact or is that forcing a penalty? (For example, if my alliance is playing against 469 at the MARC and we put a robot on the bump right next to them, would we get a red card if somebody pushed that bot off the bump?)

My gut feel is that getting pushed in would be be considered forcing a penalty and not called. However, if the team that got pushed in did not try to immediately get out, it would then be a penalty. Getting pushed in isn't an excuse for having 2 robots playing defense in the opponents home zone.