Originally Posted by Armando (Post 683600)

what type of defensive moves can you do? i heard that you can knock an opponents ball out of the ring

Originally Posted by EricH (Post 683619)

Do that too often, and the refs might call it.

Originally Posted by Drwurm (Post 683622)

One thing you can do is block a hurdle if the opposing team no longer has control of the trackball being hurdled. This means that you could park a lift or an arm in front of a "shooter"-bot's trajectory and keep them from hurdling.

Originally Posted by Armando (Post 683600)

what type of defensive moves can you do? i heard that you can knock an opponents ball out of the ring

Originally Posted by jgannon (Post 683624)

Do you see something in the manual that tells you that, or is it just a gut feeling? I'm pretty sure that it's a legitimate strategy, so long as you don't take possession of the ball. Maybe not particularly worthwhile, but legit.

Originally Posted by Daniel_LaFleur (Post 683632)

Knocking the ball out of the ring is allowed, but might be considered un-GP by some refs ... so be careful with that one. Also be careful playing "keep away" with the opponents ball.

Originally Posted by M. Krass (Post 683635)

I think it'll all be about bumping with no intention to pass, rubbing, shoving and otherwise redirecting opponents as they travel around the track. I can't imagine for a second that everyone's going to play nicely as they drive around and around. There'll be as much pushing and shoving as any recent game.

Originally Posted by JesseK (Post 683656)

When you do any of the strategies that have been mentioned above, you almost inherently take yourself out of any sort of scoring position. Sure, you could pin the ball against the wall and never move, or pin a backboard against the overpass so the opponent can never hurdle -- but the opponents have other ways to score, and you do not since you're sitting still.

At best, a bot built for a defensive strategy will be able to successfully use the strategies at spur-of-the-moment oppotunities. Still, a steady-scoring opponent will consistently outscore the defensive bot. The scores for the two alliances will be low, but I'm willing to bet that the "defensive" alliance's score will be the lower of the two almost every time.

Originally Posted by JesseK (Post 683656)

When you do any of the strategies that have been mentioned above, you almost inherently take yourself out of any sort of scoring position. Sure, you could pin the ball against the wall and never move, or pin a backboard against the overpass so the opponent can never hurdle -- but the opponents have other ways to score, and you do not since you're sitting still.

At best, a bot built for a defensive strategy will be able to successfully use the strategies at spur-of-the-moment oppotunities. Still, a steady-scoring opponent will consistently outscore the defensive bot. The scores for the two alliances will be low, but I'm willing to bet that the "defensive" alliance's score will be the lower of the two almost every time.

Originally Posted by JesseK (Post 683656)

When you do any of the strategies that have been mentioned above, you almost inherently take yourself out of any sort of scoring position. Sure, you could pin the ball against the wall and never move, or pin a backboard against the overpass so the opponent can never hurdle -- but the opponents have other ways to score, and you do not since you're sitting still.

At best, a bot built for a defensive strategy will be able to successfully use the strategies at spur-of-the-moment oppotunities. Still, a steady-scoring opponent will consistently outscore the defensive bot. The scores for the two alliances will be low, but I'm willing to bet that the "defensive" alliance's score will be the lower of the two almost every time.

Originally Posted by AdamHeard (Post 683661)

All of those strategies are losing propositions; scoring is where its at this year.

Originally Posted by M. Krass (Post 683635)

I think it'll all be about bumping with no intention to pass, rubbing, shoving and otherwise redirecting opponents as they travel around the track. I can't imagine for a second that everyone's going to play nicely as they drive around and around. There'll be as much pushing and shoving as any recent game.

Originally Posted by Capt. Quirk (Post 683671)

I think teams that use that strategy will end up with to many penalty points assed to themselves.

I think there is a great deal of strategic defenses (without giving up on scoring) , but not for teams with the "A" type personalities that are going for the big points. There are to many weaknesses for those "A" type teams, that rookie teams (and the TrackBall) could easily spoil.

Originally Posted by firstbots195 (Post 683680)

This is the year for the best defense being an amazing offense. Specializing in defense is not a good idea. Defense doesn't win matches. It helps but the ideal alliance will need three amazing scorers that are not going to be interfered with much by ramming. Some NASCAR style defense will be played such as ramming and bumping corners. We might see a bump and run move for position on the field.

Originally Posted by M. Krass (Post 683677)

Penalties based upon what?

Originally Posted by Capt. Quirk (Post 683919)

<G37> "In all cases involving ROBOT-to-ROBOT contact, the TEAM may
receive a PENALTY and/or their ROBOT may be disqualified if the interaction is
inappropriate or excessive."

I believe they are try to get away from last years bumping & shoving

Originally Posted by Capt. Quirk (Post 683919)

<G37> "In all cases involving ROBOT-to-ROBOT contact, the TEAM may
receive a PENALTY and/or their ROBOT may be disqualified if the interaction is
inappropriate or excessive."

I believe they are try to get away from last years bumping & shoving

Originally Posted by GDC

<G37> ROBOT to ROBOT Interaction - Strategies aimed solely at the destruction, damage, tipping
over, or entanglement of ROBOTS are not in the spirit of the FIRST Robotics Competition
and are not allowed. In all cases involving ROBOT-to-ROBOT contact, the TEAM may
receive a PENALTY and/or their ROBOT may be disqualified if the interaction is
inappropriate or excessive. However, it is noted that FIRST Overdrive is a highly interactive
game. Robust construction of ROBOTS will be very important in this high-speed
competition. ROBOTS should be designed to withstand the high-speed contact that will
occur during the MATCH. Appropriate contact is allowed under the following guidelines:
a. High speed accidental collisions are likely to occur during the MATCH, and are an
expected part of the game. However, high-speed intentional ramming is not acceptable
and will be penalized.
b. Contact within the BUMPER ZONE is generally acceptable.
c. Contact outside of the BUMPER ZONE is generally not acceptable, and will result in a
PENALTY. The offending ROBOT may be disqualified from the MATCH if the offense is
particularly egregious or if it results in substantial damage to another ROBOT. However,
incidental contact outside of the BUMPER ZONE will not be penalized.
d. If a ROBOT extends outside of the perimeter of the STANDARD BUMPERS (the
perimeter of the bumpers is the polygon defined by the outermost corners of each
STANDARD BUMPER segment), it is responsible for the extension's contact with other
ROBOTS. The ROBOT must not use the extension to contact other ROBOTS outside of
the BUMPER ZONE. Likewise, other ROBOTS will not be responsible for contact with
the extension outside of the BUMPER ZONE. Again, incidental contact will not be
penalized.
e. Extension to extension contact between two ROBOTS with appendages outside the
ROBOT perimeter of the STANDARD BUMPERS will generally not be penalized.
f. Contact with a tilted ROBOT outside the BUMPER ZONE (particularly if resulting from
contact within the BUMPER ZONE) will generally be considered incidental contact.
g. A ROBOT may not attach to and/or climb onto a ROBOT on an opposing ALLIANCE
(doing so will be interpreted as an attempt to damage an opposing ROBOT, and will be
penalized as such).
h. Use of any sloped or angled feature of the ROBOT as a wedge to overturn an opposing
ROBOT is explicitly prohibited, and will be assessed as a violation of Rule <R19>.

Originally Posted by Capt. Quirk (Post 684005)

I sincerly hope it won't be all about pushing and shoving, there isn't a central goal like the last two years. So there no reason to try and push some one away. They seemed to give the Hurdling robots adequate penalty protection in the rules.

If it does come down to that, I believe that it's a counter-productive strategy for both alliances.

Originally Posted by Swampdude (Post 683701)

I think defense as well as offense will be a part of every lap you make. If my alliance knows team x can hurdle, then that team can expect a poke at the ball thier trying to collect each time one of my alliance partners passes them, which is 3. Not to mention, they have 2 alliance partners going by, and 4 balls. So hopefully you can all imagine how hard it's going to be to get one of those balls up off the ground to hurdle it. Herding, and "de-herding" quickly is the trick.

Originally Posted by Rick TYler (Post 724779)

I was surprised not to see this in any of the Regionals I've witnessed:

Setting: Red alliance has two great hurdlers and a speedy lapper. Blue has two hurdlers and a third bot that can herd and descore, but has a marginally useful arm that might be able to hurdle once a match if no one nudges them.

Why wouldn't blue have their third robot simply POSSESS a red ball for the entire match? The way the rules are written, this would cost blue a single 10-point penalty, but would deprive red of 30-50 hurdling points. Seems like a no-brainer role for a weak third bot in an alliance -- the red hurdlers play with only one ball between them, but the blues get two. What am I missing?

Originally Posted by Cowmankoza (Post 724782)

The idea that your missing is that continually violating a rule can earn your team a yellow card or potentially a DQ

Originally Posted by Rick TYler (Post 724812)

There are six rules that specifically state that repeated violations can lead to disqualification. G29 is not one of them.

Interestingly, in "The Game" rules, rev G, the term "YELLOW CARD" is used in <G41> but not in any other rule. The YELLOW CARD and RED CARD rules appear in <T05>: "The Head Referee may assign a YELLOW CARD as a warning of egregious ROBOT or team member behavior." There is no definition of "egregious" but I would argue that violation of a game rule is not in and of itself egregious. Several robots in Seattle committed at least a dozen G22 errors (one robot managed four in a single match), and not one of them was yellow-carded. In the rules, only <G41> is specifically eligible for a yellow card for repeated violations. If the GDC took time to single out <G41>, why wouldn't they mention other rules?

As it turns out, I'd be in favor of adding <G29> to the "yellow card" rules with <G41>, but the question here was, has anyone tried it?

Originally Posted by M. Krass (Post 724819)

There're all sorts of situations wherein one may intentionally violate the rules and draw a penalty but come out ahead. I have not seen this sort of behavior receive a yellow card.

In Seattle, we intentionally violated G22 one and almost again a second time.

Originally Posted by M. Krass (Post 724819)

In Seattle, we intentionally violated G22 once and almost again a second time.

Originally Posted by EricH (Post 724829)

Was a partner stuck on the overpass?

Originally Posted by Rick TYler (Post 724779)

Why wouldn't blue have their third robot simply POSSESS a red ball for the entire match? The way the rules are written, this would cost blue a single 10-point penalty, but would deprive red of 30-50 hurdling points. Seems like a no-brainer role for a weak third bot in an alliance -- the red hurdlers play with only one ball between them, but the blues get two. What am I missing?

Originally Posted by d.courtney (Post 724864)

Why not block the other ball from play while your at it? I honestly would love to see the refs reaction to someone in procession of an opponents ball while blocking the teams from getting the other one which is in a corner, though thats just asking to be yellow carded.

Originally Posted by Rick TYler (Post 724779)

I was surprised not to see this in any of the Regionals I've witnessed:

Setting: Red alliance has two great hurdlers and a speedy lapper. Blue has two hurdlers and a third bot that can herd and descore, but has a marginally useful arm that might be able to hurdle once a match if no one nudges them.

Why wouldn't blue have their third robot simply POSSESS a red ball for the entire match? The way the rules are written, this would cost blue a single 10-point penalty, but would deprive red of 30-50 hurdling points. Seems like a no-brainer role for a weak third bot in an alliance -- the red hurdlers play with only one ball between them, but the blues get two. What am I missing?

Originally Posted by dtengineering (Post 724896)

Interestingly our team DID take possession of an opponent's trackball in Portland, entirely by mistake. The rest of the drive team was yelling at our (normally very calm and collected and "on the ball") driver... "NO NO WRONG COLOUR" but he grabbed the ball anyway.

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.

Originally Posted by Qbranch (Post 725143)

We've seen that one, especially at buckeye. All you have to do is cut them off new-yorker style... (aka get just a little in front of them and make a hard right into their path)... and you get your ball back. :D

-q

Originally Posted by NOV8R (Post 725206)

This discussion reminds me of one of my favorite cartoons where there are two settlers under indian attack crouched under a wagon with a burning arrow in the side. The caption on the cartoon is one settler asking the other "Are they (the indians) allowed to do that?" Good defense is not boring to those of us who like to come up with innovative ways to do it.

Originally Posted by NOV8R (Post 725206)

This discussion reminds me of one of my favorite cartoons where there are two settlers under indian attack crouched under a wagon with a burning arrow in the side. The caption on the cartoon is one settler asking the other "Are they (the indians) allowed to do that?" Good defense is not boring to those of us who like to come up with innovative ways to do it.

Originally Posted by Qbranch (Post 725650)

... go around the other side of the rack and knock it off from that side...

-q

Originally Posted by NOV8R (Post 725028)

Our robot was designed from the begining to pin the opposition's ball against the wall. By designed I mean special vertical aluminum tubes (24 inch high) that pin the ball against the wall. We also have a way of descoring the ball during hybird and the end of the game, but our primary strategy is keeping the ball from good opposition hurdlers. As regionals have progressed we're more encouraged we have a viable way of playing defense. So how well has it worked for us? We'll tell you this weekend. Our regional (Denver) is this week.

Originally Posted by NOV8R (Post 725332)

How the ball is pinned can be innovative. That's just one part of our overall strategy and play book. We can also take the ball off the overpass on the move and make 2-3 lines during hybird. Depending on the opposition we can just run laps and herd as well in teleoperated. One thing for sure we won't do is roll over and let the opposition hurdle at will. If you want to see those kind of matches lobby the GDC to only have one robot on the field at a time. In addition to a retired engineer I'm also an ex Air Force fighter pilot and learned a long time ago the value of playing assertive (not agressive) defense.

Originally Posted by Cory (Post 725103)

I must admit, I find the pinned ball in the corner strategy exceedingly boring.

Originally Posted by Rick TYler (Post 727780)

I'm still willing to pay up to six Krispy Kreme donuts to the first team that picks up and possesses an opponent's track ball for an entire match. I want to see how referees would rule on this...

(Maybe someone could try it during practice at New York this week just to get a ruling?)

Originally Posted by Rick TYler (Post 727780)

I'm still willing to pay up to six Krispy Kreme donuts to the first team that picks up and possesses an opponent's track ball for an entire match. I want to see how referees would rule on this...

(Maybe someone could try it during practice at New York this week just to get a ruling?)