Originally Posted by XXShadowXX (Post 724963)

this years defense can be played like thus, my team played defense during the semi finals in west michigan ill post the links.

http://www.thebluealliance.net/tbatv...p?matchid=8664
http://www.thebluealliance.net/tbatv...p?matchid=8711

We herded our oppents trackballs around the track (gives them 2 points, but which would you rather have them score 2 or 8 points)? Basically you play a long game of keep away, don't let your oppent caputure the trackball.
You can't see the finals which i believe that we were at our best in stopping of the oppents scoring.

Originally Posted by daf (Post 724918)

I'm glad this thread came back up. I've been wondering how defense could be played after seeing the lack of it in just about every regional I've witnessed.

It looks to me as though defense itself is not a very good strategy unless it is "on the move" such as knocking an opponent trackball clockwise etc. But the best defense which I unfortunately have yet to see is what everyone else has already brought up: just taking an opponent trackball. How much harder would it be just to pin it in a corner rather than possessing it? You accomplish the same thing without receiving a penalty. The two best alliance members could just rack up the points while the third bot can be put on the task of pinning an opponent trackball and taking it out of the game. It seems to me like shutting down your opponents opportunity to score without even getting penalized does more for your alliance than just goin around the tack does. If you could get your hands on an opponent trackball early in the match, you take out half of your opponents points. I really want to see this strategy used in Atlanta (just not against my team:D ). My only fear is that if this strategy is used to often and the game turns into one on one trackballs, the refs would do something to counteract this. I don't think this strategy is what first was aiming for when designing the game (but I do like it a lot). If it's overused, I bet a rule will be made along the lines of "you can't pin an opponent trackball for more than 6 seconds" or something like that.

Originally Posted by waialua359 (Post 725024)

that strategy is actually something that many teams have talked about and have tried doing. Doing it with success is another story.
That is what we believed all along was the "best" legal strategy!

Here's food for thought?? Has anyone seen team 224's robot?
They have the most unique way that I've seen in controlled herding of the ball. I wonder if its legal in doing the same for the opponents ball.
Once they get a ball, you cant steal it from them. Technically, they dont grab the ball at all.

I'd like to hear comments from the GDC on the legality of that. If it is, they could potentially be the best at defense at CMP, hands down!

Originally Posted by JB987 (Post 725057)

How hard would it be for an official to rule a "pinned" ball as a captured ball" and cite this?...POSSESSION: Controlling the position and movement of a TRACKBALL while the TRACKBALL is supported or captured by an ALLIANCE shall be considered POSSESSION of the TRACKBALL.
Aren't you indeed controlling the position of the ball and isn't it "captured" if your robot pins the ball between it and the wall such that another bot can not make contact with it?

Originally Posted by The Game

A TRACKBALL shall be considered “captured” by a ROBOT if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the TRACKBALL remains in approximately the same position relative to the ROBOT. Both the “supported” and “captured” conditions include the case where the TRACKBALL is also in contact with the floor.

Originally Posted by Vikesrock (Post 725059)

The rule goes on to define captured. It's definition of captured requires the ball to maintain the same position relative to the robot if the robot were to move. If you are pinning the ball against the wall it will not keep the same relative position to the robot when you move so it should not be considered possession.

Originally Posted by Cory (Post 725103)

I must admit, I find the pinned ball in the corner strategy exceedingly boring. Totally within the rules, but not at all entertaining. I don't claim to be a mind reader, but I can't imagine the GDC wished for teams to just sit there and block access to the balls for the entire match.

Originally Posted by Travis Hoffman (Post 725115)

I suggest treating a trackball as a "stack o' bins" from 2003, and protecting it thusly - by parking the trackball against the field border and patrolling an arc around it, keeping your bot between the ball and would be acquirers. Then there is no active pinning of the ball, and there can be no doubt of the legality of your defensive maneuver. If it looks as if you're going to lose perimeter integrity, poke the ball clockwise into another quadrant - preferably into the opposing homestretch. Not only do the assailants have to waste time completing a lap to get the ball, they then have to do ANOTHER lap to reestablish the trackball as a scoreable object.

Originally Posted by IndySam (Post 683649)

A defensive bot can slowly herd an opponents ball preventing them from scoring. A couple of them could play a game of keep away. Could get ugly having teams jostling fort a ball.