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falconmaster
01-14-2010, 01:16 PM
We have worked out all scenarios we can and here is the data.
http://spreadsheets.google.com/pub?key=th6XxAedlL9Szm14-A7zlPw&gid=1
My question is what do we do when the time is negative? Look at the bottom of the chart, spread sheet. If we are doing this wrong, please help us.

Vikesrock
01-14-2010, 01:22 PM
It is probably a good question to ask the Q&A to be absolutely sure, but negative time remaining in the match will never be reached so my assumption is that a ball with a calculated negative return time will not incur a penalty even if not returned to the field.

Gdeaver
01-14-2010, 01:38 PM
The GDC is especially irritating this year.

SteveGPage
01-14-2010, 01:39 PM
We have worked out all scenarios we can and here is the data.
http://spreadsheets.google.com/pub?key=th6XxAedlL9Szm14-A7zlPw&gid=1
My question is what do we do when the time is negative? Look at the bottom of the chart, spread sheet. If we are doing this wrong, please help us.

I think that you need an additional column. When the original ball comes into the goal, there are at that time 0 "other" unexpired balls in the station. So at time = 120, the original ball must be returned at 109 seconds.

Here is the formula from the DOGMA document

T expire (x) = T score { 11 + (4 * # other unexpired balls currently in Station) }

Document is found here: http://www.usfirst.org/uploadedFiles/Community/FRC/Game_and_Season__Info/2010_Assets/DOGMA_RevA.pdf

Your main question about negative time, still applies, and while I would believe that you don't have to return a ball to the field that has a negative time associated with it - it still would be good for GDC to address through the Q&A forum.

Thanks!

Steve

EricH
01-14-2010, 01:50 PM
I was talking this over a bit elsewhere, and here's something to think on.

It's Match 3 of the Championship Finals. One alliance is up by one point when the buzzer sounds. When the final score shows, though, the other alliance wins by 1 point due to penalties. No flags were thrown, and no DOG penalties were assessed during the match. However, two balls entered in the last 11 seconds and were not returned. The system automatically assessed penalties after the match was over (over being defined in <G03>).

Do you want to be in the shoes of the GDC/scoring system designers/programmers when/if that unfolds? Neither would they. (Especially if it had happened in previous matches.)

Go ahead and ask in Q&A, but I think they've already thought of this situation and will have planned to avoid it already.

Kevin Sevcik
01-14-2010, 02:26 PM
I think the meaning of a negative result out of the formula is fairly obvious. The result of the formula is clearly stated as the time on the match countdown clock by which you need to get a ball back on the field. The countdown stops at 0, so it will never reach a negative number, so those balls don't need to be returned to the field. It's the only result that makes sense. The only other options are to force teams to return balls after the match ends, which is pointless and delaying, or to clip the formula result at 0, which means you get penalized for that last second goal you made that you literally had no time to return to the field.

So I think the smart move is to have human players hold any balls scored in the last 11 seconds of a match. Or possibly more if you've got a big backlog.

falconmaster
01-14-2010, 02:52 PM
I think the meaning of a negative result out of the formula is fairly obvious. The result of the formula is clearly stated as the time on the match countdown clock by which you need to get a ball back on the field. The countdown stops at 0, so it will never reach a negative number, so those balls don't need to be returned to the field. It's the only result that makes sense. The only other options are to force teams to return balls after the match ends, which is pointless and delaying, or to clip the formula result at 0, which means you get penalized for that last second goal you made that you literally had no time to return to the field.

So I think the smart move is to have human players hold any balls scored in the last 11 seconds of a match. Or possibly more if you've got a big backlog.

Thanks that makes sense

TomH
01-14-2010, 07:06 PM
That seems questionable in my mind, for although you can hold balls in your corral in the last 11 seconds, it still seems like if a ball comes in a the 11 or 10 second mark, you might want to attempt to still get that ball back on the feild, but have some delay so that i may get on the feild when there is little time to take ANY evasive action to attempt to score. That is a good question though. It seems that holding the balls is a good strategy, but also, look at the option that you could have an alliance member, or even your own team, that is ready to get one more ball in, although it is the finale and robots may be hanging everywhere, it is a combonation of both strategy and design weither you will attempt for 2 and hang (or 3 off another bot) or try to score 1 ball for one point. The rules of seeding are diffrent from previous games, so maybe 1 point for a 12-11 win may be more giving instead of a 13-11 match, because 1 point can make a big diffrence in a low scoring game with hge effects on the placement of your team. SO holding the balls can be a good strategy as long as you pay attention to the clock, but maybe if you have the advantage of real-time scoreing (although not always accurate, but in a game with electronic goal scoring it can) you can make a better decision that can help your overall seeding.

Kevin Sevcik
01-14-2010, 09:59 PM
Actually, come to think of it, unless you have a significant backlog, then deciding what to do with balls the few negative time balls is a moot point. I can't find the thread, but someone timed the NH ball return at 8-10 seconds after the ball was put on the rails. And atleast 5 seconds for an HP team to even get a ball on the rails. So if you get a ball in your chute in the last, say, 15 seconds of the game, there's no chance of your HPs getting the ball to the rails in time for it to drop on the field before time hits 0.

Bill_B
01-15-2010, 02:05 PM
When returning balls, especially in the last seconds, the HPs and everyone else needs to consider what could happen to the returned ball. If all your alliance 'bots are suspended or not in the midfield for some reason, the other side could score that ball. If you're leading the match, you might WANT them to score to get a higher seeding score (if you're in Q-round). If all opponents are elevated/suspended AND you're ahead, keep it. If you're behind by more than one and have no prospect of scoring it, keep it. If you could tie or win by scoring that ball, you can't get it onto the midfield soon enough! Of course, things are slightly different for the Eliminations.

Who wants to make a chart or decision table? Who'd like to see one?

Daniel_LaFleur
01-15-2010, 02:24 PM
I think the meaning of a negative result out of the formula is fairly obvious. The result of the formula is clearly stated as the time on the match countdown clock by which you need to get a ball back on the field. The countdown stops at 0, so it will never reach a negative number, so those balls don't need to be returned to the field. It's the only result that makes sense. The only other options are to force teams to return balls after the match ends, which is pointless and delaying, or to clip the formula result at 0, which means you get penalized for that last second goal you made that you literally had no time to return to the field.

So I think the smart move is to have human players hold any balls scored in the last 11 seconds of a match. Or possibly more if you've got a big backlog.

While this makes perfect sense to me, nowhere do I see any reference in the rules that state that the countdown stops at 0, hence unless there is a ruling otherwise on the FIRST forums, I'll have my human player return all the balls to the field.

It takes ~ 8+ seconds for the ball to roll down the track so most balls returned during this time will be useless.

HyperPiGuy
01-30-2010, 10:02 AM
if you score with 10 seconds left according to the DOGMA you have negative 5 seconds to get the ball back in play. so as soon as you score you get a penalty.

GaryVoshol
01-30-2010, 12:23 PM
if you score with 10 seconds left according to the DOGMA you have negative 5 seconds to get the ball back in play. so as soon as you score you get a penalty.Please read again. You would have until the clock reached -1 seconds to return the ball before PENALTY. (Or -5 seconds on the clock, if there was another unreturned ball in your end.)

Since the clock will never reach that time, does that mean you will have infinity before a PENALTY is applied? Or is the game artifically extended in order to assess the PENALTY? Or will the PENALTY apply when the clock hits 0? The GDC hasn't yet answered, maybe because it hasn't yet been asked.