Defense, It's still here.

[Zyik]

Many people have been complaining about the fact that "There's no defense this year." I don't believe this, every year there has been some way of playing defense. It's true there won't be as much of the same kind of defense as Rack-and-Roll or Aim High, but they were different games. One thing 973 can do well is defense so I've put a lot of thought into this.

Isn't it still defense if you knock the opposing alliances balls off the overpass? This stops them from getting points, which is what I always understood defense to be.

Or how about "nudging" as the manual calls it, a robot trying to get into place to hurdle? Think about it, what happens if you get behind them and push them over the line? They're not allowed to turn around and go back and try again like Rack-and-Roll, if you do it right they have to go all the way around the track to try again, or at least close to that. If you really play your cards right you might even manage to get their herding points reduced. Do it suddenly so that they don't manage to get rid of the ball, if it stays in contact with the robot as it crosses the line. If you're pushing the robot you shouldn't be in contact with their trackball.

This falls under <G10> Each TRACKBALL that has CROSSED its own FINISH LINE while not in contact with a ROBOT of the same ALLIANCE will earn 2 points. A TRACKBALL that has CROSSED its own FINISH LINE which contacts ROBOTS of both ALLIANCES while CROSSING will earn 2 points.

An example of this: Lets say I have a typical six wheel kit bot and the "only" thing it can do is race around the track for points. Lets also say that one of the robots on the opposing side is a hurdling robot that operates via scissor lift and omni drive. (Nothing against scissor lifts, just an example) The hurdling robot has a Trackball in their possession and is just rounding the corner to enter their alliance zone. I should be able to use my kit bot and push the hurdling robot over their alliance line fairly easily. They won't have started to hurdle yet so G42 is not in effect. The trackball will cross the line and will have to make the rounds around the track again in order to be hurdled. If I just have my kit bot harass the hurdling bot every time they get near their scoring area I'm playing a success defense. I'm also scoring points by going around the track. Win-Win.

<G42> Protection While HURDLING – A ROBOT in the process of HURDLING shall not be subjected to overt, blatant, or aggressive contact that interferes with the HURDLING attempt. Each incident will be PENALIZED. Bumping to signal to pass (see Rule <G38>) a HURDLING ROBOT is permitted if no passing lane is open (see Rule <G43>). Incidental contact while passing the HURDLING ROBOT or otherwise engaged in normal game play is permitted.


This is in no way saying I'm going to build a kit bot, but this would be a way for a rookie team with many resources to build a good robot.

Is this un-GP in anyones mind? Any more ideas about how defense can be played in Overdrive? It's different from previous games we've seen yes, but it's still FIRST and I haven't seen a FIRST game yet that you can't find some way of playing defense in.

Part of this I posted in another thread previously, but I think that it dissevers a thread of it's own. Apologies in advance for errors, it's 5:21 am and I haven't gotten any sleep

[galewind]

or how about if you know that an opponent is good at hurdling, so instead you herd their ball slowly around the track? You're giving them two points per lap, but stopping them at getting 8!

[SuperJake]

An example of this: Lets say I have a typical six wheel kit bot and the "only" thing it can do is race around the track for points. Lets also say that one of the robots on the opposing side is a hurdling robot that operates via scissor lift and omni drive. (Nothing against scissor lifts, just an example) The hurdling robot has a Trackball in their possession and is just rounding the corner to enter their alliance zone. I should be able to use my kit bot and push the hurdling robot over their alliance line fairly easily. They won't have started to hurdle yet so G42 is not in effect. The trackball will cross the line and will have to make the rounds around the track again in order to be hurdled. If I just have my kit bot harass the hurdling bot every time they get near their scoring area I'm playing a success defense. I'm also scoring points by going around the track. Win-Win.

This seems to differ from my interpretation of the rules. Check this out: if you were to push the robot from the Hurdling position to cross the finish line, that would be a 32" push (the width of the Overpass) since one would presumably be hurdling from their own Home Stretch and the finish line is at the end of the Home Stretch. This amount of contact would not be in the spirit of <G38> as this would no longer be a "bump" but a push.


<G38>Signal To Pass – A ROBOT may indicate a desire to pass an IMPEDING ROBOT by approaching the opponent ROBOT and “bumping” the back of the opponent ROBOT (relative to the Direction of Traffic).

All “bump to pass” signals must be made with or against a STANDARD BUMPER and inside the BUMPER ZONE, or
If in POSSESSION of a TRACKBALL, the ROBOT may “bump” the IMPEDING ROBOT with the TRACKBALL outside the BUMPER ZONE, providing the contact is made exclusively with the TRACKBALL.

Signaling a desire to pass by “bumping” must still be executed within the constraints indicated in Rule <G37>. E.g. high-speed intentional ramming or using the TRACKBALL to intentionally damage or topple an opponent are still not acceptable actions, and will be penalized.

However, there could be the potential of several robots attempting to Hurdle, but not yet in the act of hurdling, that could bring <G40> into play which could penalize the hurdling robot for impeding traffic.

Another thing to note is that <G42> seems to balance the game play such that anyone that looks like they are attempting to hurdle would be given the benefit of the doubt. It will be interesting to see how the Referees decide to enforce this.

[Jeff Rodriguez]

The hurdling robot has a Trackball in their possession and is just rounding the corner to enter their alliance zone. I should be able to use my kit bot and push the hurdling robot over their alliance line fairly easily. They won't have started to hurdle yet so G42 is not in effect. The trackball will cross the line and will have to make the rounds around the track again in order to be hurdled. If I just have my kit bot harass the hurdling bot every time they get near their scoring area I'm playing a success defense. I'm also scoring points by going around the track. Win-Win.

<G42> Protection While HURDLING – A ROBOT in the process of HURDLING shall not be subjected to overt, blatant, or aggressive contact that interferes with the HURDLING attempt. Each incident will be PENALIZED. Bumping to signal to pass (see Rule <G38>) a HURDLING ROBOT is permitted if no passing lane is open (see Rule <G43>). Incidental contact while passing the HURDLING ROBOT or otherwise engaged in normal game play is permitted.



In the situation you pose, you say that the robot is not in the process of hurdling yet. I disagree. Let's look at the definition of hurdling:

HURDLING: The act of completing a HURDLE. To be considered in the process of HURDLING, the ROBOT must:
• be in its own HOME STRETCH, and
• be in POSSESSION of a TRACKBALL, and
• be moving toward the OVERPASS and/or elevating the TRACKBALL so that the top of the TRACKBALL is higher than the LANE DIVIDER.

For clarity let's say your pushing my robot. I have possession of a ball and you have just pushed me over the lane marker into my home stretch. According to the definition of hurdling I'm now in the process of doing it. My robot satisfies all three of those conditions: I'm in the Home Stretch, I have a ball and I'm moving toward the overpass (maybe because you're pushing me, but it doesn't specify that).

Now, since my robot is in the process of hurdling, <G42> is in effect and the question is are you breaking <G42>? Is a steady push considered overt, blatant, or aggressive contact that interferes with the HURDLING attempt? I don't know for sure. The push is not a signal to pass, nor is it incidental contact. I'd say it's something to be asked in the Q&A.

[Bongle]

Another defensive maneuver I saw posted yesterday:

Let's say your robot and an opposing robot are in your home stretch. The opposing robot is herding a trackball. If you bump the trackball out of your homestretch* into the previous quad (i.e. move the trackball clockwise), then you prevent them from hurdling for 8 points or herding for 2 points when they finish their current lap. They won't be able to score substantial herding or hurdling points for 6 quads of movement.

*This is legal so long as your robot itself does not cross the lane divider between your home stretch and their post-home-stretch. IIRC, you can still move clockwise within a quad, just not clockwise from quad to quad.

I'm happy about the no-defense type rules. In previous games, even those that included low cost-of-entry scoring methods like the low goals in Aim High, it was often much more profitable to abuse the opponents to prevent them from scoring than it was to attempt to do the low-point option. This game basically forces you to either be a clever defender (no pinning, no impeding, no bashing while hurdling, etc) or actually try and get points yourself. Rack 'n Roll was deathly boring because it was far, far, easier to build an effective defender than an effective offender. In Aim High, a well-designed offense robot could be effectively immune from defense since they could score from anywhere.

[Tottanka]

Another defensive maneuver I saw posted yesterday:

Let's say your robot and an opposing robot are in your home stretch. The opposing robot is herding a trackball. If you bump the trackball out of your homestretch* into the previous quad (i.e. move the trackball clockwise), then you prevent them from hurdling for 8 points or herding for 2 points when they finish their current lap. They won't be able to score substantial herding or hurdling points for 6 quads of movement.

*This is legal so long as your robot itself does not cross the lane divider between your home stretch and their post-home-stretch. IIRC, you can still move clockwise within a quad, just not clockwise from quad to quad.

Those are my thoughts exactly.
Now, question is, maybe it is worth for you to just stay in their home strech zone the whole game and dont let them score. That is deffinately defence.

[Justin M.]

While going for a defensive strategy is possible, remember that the scoring may wind up evening it's way out. By putting one robot out of commission, you are also putting your own robot out of commission scoring wise. Even if you can't herd or hurdle trackballs, you can still get that 2 points for crossing your finish line. This leaves 2 other robots to still go and score. I don't believe committing to a defensive strategy will be as beneficial as it sounds right now.

In response to your strategy, the refs may declare your pushing to be an obstruction of traffic or unsportsmanlike. You can also cancel out by simply raising your arm/trackball above the overpass once you get into your homezone. That is at least ONE of the characteristics of hurdling and that protects you under <G42>.

[Daniel_LaFleur]

I got a question.

Since they have removed the 6' height restriction in the opponents home stretch, does that mean teams can block hirdling attempts?

[Justin M.]

I got a question.

Since they have removed the 6' height restriction in the opponents home stretch, does that mean teams can block hirdling attempts?

It should have no effect on the hurdle protection rule. A hurdle attempt can only be done in your own homezone.

[Cory]

Many people have been complaining about the fact that "There's no defense this year." I don't believe this, every year there has been some way of playing defense. It's true there won't be as much of the same kind of defense as Rack-and-Roll or Aim High, but they were different games. One thing 973 can do well is defense so I've put a lot of thought into this.

Isn't it still defense if you knock the opposing alliances balls off the overpass? This stops them from getting points, which is what I always understood defense to be.

Or how about "nudging" as the manual calls it, a robot trying to get into place to hurdle? Think about it, what happens if you get behind them and push them over the line? They're not allowed to turn around and go back and try again like Rack-and-Roll, if you do it right they have to go all the way around the track to try again, or at least close to that. If you really play your cards right you might even manage to get their herding points reduced. Do it suddenly so that they don't manage to get rid of the ball, if it stays in contact with the robot as it crosses the line. If you're pushing the robot you shouldn't be in contact with their trackball.

This falls under <G10> Each TRACKBALL that has CROSSED its own FINISH LINE while not in contact with a ROBOT of the same ALLIANCE will earn 2 points. A TRACKBALL that has CROSSED its own FINISH LINE which contacts ROBOTS of both ALLIANCES while CROSSING will earn 2 points.

An example of this: Lets say I have a typical six wheel kit bot and the "only" thing it can do is race around the track for points. Lets also say that one of the robots on the opposing side is a hurdling robot that operates via scissor lift and omni drive. (Nothing against scissor lifts, just an example) The hurdling robot has a Trackball in their possession and is just rounding the corner to enter their alliance zone. I should be able to use my kit bot and push the hurdling robot over their alliance line fairly easily. They won't have started to hurdle yet so G42 is not in effect. The trackball will cross the line and will have to make the rounds around the track again in order to be hurdled. If I just have my kit bot harass the hurdling bot every time they get near their scoring area I'm playing a success defense. I'm also scoring points by going around the track. Win-Win.

<G42> Protection While HURDLING – A ROBOT in the process of HURDLING shall not be subjected to overt, blatant, or aggressive contact that interferes with the HURDLING attempt. Each incident will be PENALIZED. Bumping to signal to pass (see Rule <G38>) a HURDLING ROBOT is permitted if no passing lane is open (see Rule <G43>). Incidental contact while passing the HURDLING ROBOT or otherwise engaged in normal game play is permitted.


This is in no way saying I'm going to build a kit bot, but this would be a way for a rookie team with many resources to build a good robot.

Is this un-GP in anyones mind? Any more ideas about how defense can be played in Overdrive? It's different from previous games we've seen yes, but it's still FIRST and I haven't seen a FIRST game yet that you can't find some way of playing defense in.

Part of this I posted in another thread previously, but I think that it dissevers a thread of it's own. Apologies in advance for errors, it's 5:21 am and I haven't gotten any sleep

I think this is a blatant violation of the intent of the rules.

Any way that the rules can be read to allow defense (pushing/interaction between one robot that is trying to stop another from getting to a certain location, or from doing a certain task) seems to be complete lawyerism to me.

I think everyone is sick of seing boxes on wheels that just run around the field bashing the heck out of anyone who can score (Let's see how long it takes for Travis to come in here and tell me some people enjoy it :P). My understanding of the rules is that they are intended to keep this from happening.

I would be very disappointed if teams took to subterfuge to attempt to play defense (ie: "bumping" to pass, by pushing a team halfway across the field, etc).

[Travis Schuh]

I think everyone is sick of seeing boxes on wheels that just run around the field bashing the heck out of anyone who can score (Let's see how long it takes for Travis to come in here and tell me some people enjoy it :P). My understanding of the rules is that they are intended to keep this from happening.


I have to say, some people do enjoy defense. There is a certain skill required to do it properly, and the teams who have figured out the trick find it fun.

Also, it is always nice to have the safety net of defense to fall back on if your offense strategy doesn't work...

-Travis

[Dan Petrovic]

Or how about "nudging" as the manual calls it, a robot trying to get into place to hurdle? Think about it, what happens if you get behind them and push them over the line? They're not allowed to turn around and go back and try again like Rack-and-Roll, if you do it right they have to go all the way around the track to try again, or at least close to that. If you really play your cards right you might even manage to get their herding points reduced. Do it suddenly so that they don't manage to get rid of the ball, if it stays in contact with the robot as it crosses the line. If you're pushing the robot you shouldn't be in contact with their trackball.

The entire robot must cross the vertical plane to have been considered as CROSSING the line as per definition of CROSSING:

CROSSING: The act of a TRACKBALL or ROBOT passing through the plane defined by a line (i.e.
LANE MARKER or FINISH LINE) when it is projected vertically upwards. A TRACKBALL or
ROBOT shall have CROSSED a line when all parts of the object, while traveling in a
counterclockwise direction, have completely passed through the plane.

So, if a team is nudged so that just their front wheels go over the line, they can back up and re-align themselves. In most cases, teams trying to hurdle will be clotheslined by the overpass as a result of said "nudging", so they wont cross the finish line. Also, I have a feeling you'd have to hit a hurdling robot pretty hard for their entire robot to cross the finish line, resulting in a 10 point penalty.

Thanks. I never thought of it this way, now we know how to avoid this type of defense.

[Tetraman]

Did anyone also see this half-loophole?

You don't need to circle the field. As long as you stay behind the lines you can stay in an area and play some interesting def.

[jdejoannis]

Someone is in denial.

Lets face it, there is less defense this year. Last year, harassing a star scorer was quite worthwhile if you had a decent drivetrain.

<G42> is unequivocal about not harassing hurdlers.

<G29> prohibits POSSESSION of opponents trackballs. Therefore playing keepaway will be difficult.

The best chance is to herd opponents trackballs whenever the chance presents itself. Basically, give it a shove in the wrong direction whenever you see it. This is slim pickings. It remains to be seen how the judges will view deliberately moving in front of herding robot.

/Jason

[Dan Petrovic]

Someone is in denial.

Lets face it, there is less defense this year. Last year, harassing a star scorer was quite worthwhile if you had a decent drivetrain.

<G42> is unequivocal about not harassing hurdlers.

<G29> prohibits POSSESSION of opponents trackballs. Therefore playing keepaway will be difficult.

The best chance is to herd opponents trackballs whenever the chance presents itself. Basically, give it a shove in the wrong direction whenever you see it. This is slim pickings. It remains to be seen how the judges will view deliberately moving in front of herding robot.

/Jason

The definition of POSSESSION a trackball is quite clear, as well.

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. A
TRACKBALL shall be considered “supported” by a ROBOT if in the estimation of a reasonably
astute observer the majority of the weight of the TRACKBALL is being borne by the ROBOT. 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.

So, if a team bumps a ball and it rolls away from them, they are considered HERDING and not in POSSESSION.

<G29> POSSESSING Opponent’s TRACKBALLS - ROBOTS may not be in the POSSESSION of a
TRACKBALL belonging to an opposing ALLIANCE. A PENALTY will be assigned for each
violation. HERDING of an opponent’s TRACKBALL and removing an opponent’s
TRACKBALL from the OVERPASS is permitted.

[Jonathan Norris]

I have a funny felling that this year is going to be alot like '05 where yes you could play some defense if you wanted to, but the opportunity for penalties is just too high. It really just depends on how the refs manage the game and basically outlaw any major interaction with scoring robots.

[Madison]

I think, perhaps with the sole exception of overt contact of a hurdling robot, defense is completely proper and viable.

I mentioned in another thread the potential, with <G36> absent, to erect a wall in front of or behind your opponent's overpass such that hurdling is impossible. Coupled with a drive that allowed you to move sideways, you could become very effective at blocking hurdling attempts while never contacting the opposing robots at all. I cannot imagine how at any time contact initiated by their robot could result in a penalty upon your team. That notion is ludicrous.

Further, despite rules about "bumping to pass," there are no specific prohibitions against gently escorting robots in one direction or another. I understand and appreciate that there are rules governing behavior in attempts to pass on the field, but those rules do not preclude me from having no intention to pass and acting accordingly.

I think we'll see more defense than a lot of folks think, but I don't know that there are many viable strategies that for defense that might require a robot design different than something designed to score.

[Daniel_LaFleur]

I think, perhaps with the sole exception of overt contact of a hurdling robot, defense is completely proper and viable.

I mentioned in another thread the potential, with <G36> absent, to erect a wall in front of or behind your opponent's overpass such that hurdling is impossible. Coupled with a drive that allowed you to move sideways, you could become very effective at blocking hurdling attempts while never contacting the opposing robots at all. I cannot imagine how at any time contact initiated by their robot could result in a penalty upon your team. That notion is ludicrous.

Further, despite rules about "bumping to pass," there are no specific prohibitions against gently escorting robots in one direction or another. I understand and appreciate that there are rules governing behavior in attempts to pass on the field, but those rules do not preclude me from having no intention to pass and acting accordingly.

I think we'll see more defense than a lot of folks think, but I don't know that there are many viable strategies that for defense that might require a robot design different than something designed to score.

Agreed. and this is what I was asking about.

With the removal of the 6' height restriction is it legal to block hurdling (not interfere with the hurdling robot)?

[dlavery]

I mentioned in another thread the potential, with <G36> absent, to erect a wall in front of or behind your opponent's overpass such that hurdling is impossible. Coupled with a drive that allowed you to move sideways, you could become very effective at blocking hurdling attempts while never contacting the opposing robots at all. I cannot imagine how at any time contact initiated by their robot could result in a penalty upon your team. That notion is ludicrous.
If you try this approach, you may need a few extra team members to help you count all your penalty points. There are a few rules that very effectively combine to prevent you from doing this.

-dave

[David Brinza]

I think there'll be plenty of defense, just not the "smash and crash" kind that FIRST is rightfully trying to discourage.

I can imagine alliance strategies involving "keep away" from their opponent's effective hurdling robots. Slow driving robots will challenge the driving skills of the "rabbits". Don't expect uninhibited scoring in Overdrive...it will be a lot harder grab trackballs and move quickly around the track than some might think.

[Jeff Rodriguez]

Did anyone also see this half-loophole?

You don't need to circle the field. As long as you stay behind the lines you can stay in an area and play some interesting def.

I'm pretty sure you'd be breaking <G40>. I bolded where.

IMPEDING Traffic – ROBOTS shall not intentionally IMPEDE the flow of traffic around the TRACK. A ROBOT will be considered to be IMPEDING traffic if it is preventing an opposing ROBOT from proceeding around the TRACK. A ROBOT can be found to be IMPEDING traffic if:
• the ROBOT is traveling slowly relative to the approaching ROBOT, and moving to prevent the approaching ROBOT from passing, or
• the ROBOT is stopped on the TRACK and there is no clear lane of passage for the opposing ROBOT, or
• the ROBOT pins an opposing ROBOT against an arena element, border, or another ROBOT
Note that a ROBOT is not IMPEDING traffic if:
• there is a clear “passing lane” around the ROBOT, or
• the IMPEDING ROBOT and the approaching ROBOT are from the same ALLIANCE (i.e. a ROBOT can not impede another ROBOT of the same ALLIANCE), or
• the ROBOT is in the process of HURDLING (except as noted in Rule <G43>).

[Madison]

If you try this approach, you may need a few extra team members to help you count all your penalty points. There are a few rules that very effectively combine to prevent you from doing this.

-dave


<G42> Protection While HURDLING – A ROBOT in the process of HURDLING shall not be subjected to overt, blatant, or aggressive contact that interferes with the HURDLING attempt. Each incident will be PENALIZED. Bumping to signal to pass (see Rule <G38>) a HURDLING ROBOT is permitted if no passing lane is open (see Rule <G43>). Incidental contact while passing the HURDLING ROBOT or otherwise engaged in normal game play is permitted.


Beyond this nothing else springs to mind, though I've just woken up. Again, I can't imagine that any contact by any opposing robot unto me can (or should) be considered overt, blatant or aggressive. The caveat is that any robot in possession of a trackball and in its home stretch can be considered to be "hurdling," and contact with them or their ball as such is a very bad thing.

In circumstances, however, where we're defending from behind their finish line and, as I suspect many teams will, they've released the ball to complete the hurdle -- that team no longer satisfies the conditions of HURDLING -- and, moreso, we are really doing nothing more than HERDING at a height of 7 feet. I can't imagine how a wall, sitting innocently on one side of the overpass and bouncing balls away, is doing anything wrong. :)

Of course, we're not building this robot, so my interest in this is almost purely academic.

[chapmatr]

Isn't it still defense if you knock the opposing alliances balls off the overpass? This stops them from getting points, which is what I always understood defense to be.

Not sure if anyone else caught this, but the rules say that if the ball is knocked off of the overpass you get points. So it doesn't matter HOW they fall, so long as they do. I just want to say that defense will be much more difficult to manage than trying to score, so I'd recommend building a tough bot that can at least do laps.

[Travis Hoffman]

I think this is a blatant violation of the intent of the rules.

Any way that the rules can be read to allow defense (pushing/interaction between one robot that is trying to stop another from getting to a certain location, or from doing a certain task) seems to be complete lawyerism to me.

I think everyone is sick of seing boxes on wheels that just run around the field bashing the heck out of anyone who can score (Let's see how long it takes for Travis to come in here and tell me some people enjoy it :P).

My understanding of the rules is that they are intended to keep this from happening.

I would be very disappointed if teams took to subterfuge to attempt to play defense (ie: "bumping" to pass, by pushing a team halfway across the field, etc).

Not very long, Cory. But perhaps my response won't be as expected as you originally thought. ;)

"Defense" cannot solely be defined this year by the extensive "pushing" interaction you describe. I do believe the GDC does not want to see robots being pushed "halfway across the field" this year. It would be akin to Tony Stewart sacrificing his car to remove an opponent from the race....not that Tony Stewart would ever do such a thing....:) I would not qualify such an act as "subterfuge", either, for it should be pretty durned obvious to the referees if such an involuntary trip were occurring in front of their eyes! However, I also do not believe this was anywhere near the type of strategy Lucy was suggesting in her original post, and she and other defensive-minded individuals are entitled to this thread discussing its legality and merits, along with any other methods of defending which are brought up.

Personally, I'd certainly like to know the GDC's intent for robot interaction during the last second moments when a team is trying to put bonus balls up and another is trying to knock them down. At this point, there is no more hurdling - teams are "capping" - freezing their balls in mid hurdle, so to speak :cool: - so are their anti-defense liberties removed during these times? Is pushing in the bumper zone ok then? Is posting straight up to block capping attempts with your arm a legal manuever? And when one defending robot is actively herding an opponent's ball, playing keep away, how aggressive can the would-be offender be in trying to retrieve their scoring object? These are all seemingly legal strategies and reasonable questions - bumper zone interaction is explicitly allowed (whenever it isn't - ha) - what kind of contact does the GDC expect and approve of during such situations? I'll be looking for these to show up on the Q/A once the system opens up.


I think everyone is sick of seing boxes on wheels that just run around the field bashing the heck out of anyone who can score (Let's see how long it takes for Travis to come in here and tell me some people enjoy it :P).


I don't think anyone enjoys watching any robot get "bashed" in the most crippling of senses, whether the damage occurs by intent (unless you are the twisted transgressor), via ignorance of the rules, or via mistakes in judgement during the heat of competition. However, it seems you wish to suggest here that all forms of defense have this negative connotation. I think this does not respect those teams who on the whole work hard every year to play defense well and play it within the rules.

And yes, I DO think teams who build those "boxes on wheels" and play that D correctly very much enjoy it when their robot is able to do something productive on the field, especially when the "glitziest" of offensive game objectives may be out of their technical reach.

The offensively proficient certainly have had ample opportunities to shine and bring excitement to many an event even in the most defensive of recent seasons - 2004, 2006, and 2007. The FIRST community rightfully celebrates the accomplishments of those who have achieved such successes. I know (boy do I) how many of us believe it shouldn't be that hard for all FIRST teams to slap together some sort of rudimentary arm and off they go just because a drive base is simple and boring and they should challenge themselves to do more, but I believe the true reality is that some teams just don't have the experience, the time, the organization, or the money. They may very well have the desire, though, and seek only a little bit of assistance from those in the know to nudge them on their way toward technological improvement. Are we fortunate ones doing enough to facilitate their growth and advancement? Or would we prefer they just stay out of our way?

For those "lost" teams, I would hope we can still reserve a bit of room for praise and recognition of their achievements, relatively miniscule they may be to those of us who are used to so much more.

In 2008, I applaud the GDC in providing a much wider variety of both offensive and defensive options that are accessible to rookies and other teams who may not necessarily be as fortunate in the resource department as those of us who can be adept at scoring each year.

[Alan Anderson]

Not sure if anyone else caught this, but the rules say that if the ball is knocked off of the overpass you get points. So it doesn't matter HOW they fall, so long as they do.

Removing the ball from the overpass after the hybrid period is over does not score any points. It would be to an alliance's advantage to leave the opposing alliance's trackballs on the overpass until just before the end of the match, and remove them at the last possible moment in order to deprive the opponents of the <G14> bonus.

During the HYBRID PERIOD, each TRACKBALL that is removed from the OVERPASS (i.e. completely removed from its initial TARGET LOCATION and not in contact with any portions of the OVERPASS) at the end of the HYBRID PERIOD will earn 8 points.

When the MATCH ends, each TRACKBALL is at least partially supported by the OVERPASS and not in contact with any ROBOT of the same ALLIANCE will earn a 12 point bonus.

[Travis Hoffman]

I think we'll see more defense than a lot of folks think, but I don't know that there are many viable strategies that for defense that might require a robot design different than something designed to score.

And this is the beauty of this year's game - I always enjoy it when teams can squeeze more strategic functionality out of one robot system.

An arm can be used for offense and defense.

A stout drive can be used for stability in guiding the balls around the field, as well as dictating where you want to be on the track when it's advantageous for you to be "over there" instead of where you're at now. Say, for when there are those moments you'd rather run on the inside track to push the quick guys to the outside of the track and negate the benefits of their speed with the longer distance they'd then have to travel to make those laps.....

[GMKlenklen]

it seems the GDC has replaced the "kitbot and bumbpers = ram" defence with something more like "kitbot and bumpers = racecar" "defence". In which you can only score points, and defensive oppertunities are also penalty opertunities.

it seems to me there are really 3 viable strategies for the teleoperated period:

run around the field

run around field with Trackball

hurdel Trackball

[Molten]

If in POSSESSION of a TRACKBALL, the ROBOT may “bump” the IMPEDING ROBOT with the TRACKBALL outside the BUMPER ZONE, providing the contact is made exclusively with the TRACKBALL.

Take note of this part of the G38 rule. I think that this shows that the original strategy of this thread is allowed. Even if it is not amongst bumper to bumper pushes. It should be allowed as long as they just use a trackball to do all of the pushing. It wouldn't be that hard to design a mechanism that would pick up the ball and hold it in front of itself in a sturdy fashion. With this, it could almost make the ball a part of itself. Of course, to do this for the entire match would cause your team mates to only have one trackball to score with so it is really a mute point. I just thought I would throw this idea out there among the masses and see what you can do with it.

Also, to all of you who believe that defense is unimportant. Just imagine a football team with no defense. Really that analogy works for any sport, football just happens to be a good example.

Finally, a humorous thought to part on. Just imagine if you were to fire that trackball as a projectile. They do not have restrictions on this like they did in the Aim High. Hard telling how fast you could get that ball to. I KNOW THIS DOES NOT GO WITH GP. I just thought it a funny picture to see a ball that size being launched at incredible speed and imagine the impact.

[Ze Møøse]

I think defense in this year's game is going to be pretty much limited to interaction with the opposing alliance's trackballs rather than playing defense against the robots themselves. In my opinion knocking an opponent's trackball back a quad as Bongle mentioned is probably the most viable defensive maneuver in this game.

[Jon Stratis]

Finally, a humorous thought to part on. Just imagine if you were to fire that trackball as a projectile. They do not have restrictions on this like they did in the Aim High. Hard telling how fast you could get that ball to. I KNOW THIS DOES NOT GO WITH GP. I just thought it a funny picture to see a ball that size being launched at incredible speed and imagine the impact.

But along with GP, if one team is trying to hurdle while another team is trying to block them, is it really the first teams fault if the second team incurs damage (or tips over, which would be a real possibility) if they are successful at blocking the ball?

[EricH]

Beyond this nothing else springs to mind, though I've just woken up. Again, I can't imagine that any contact by any opposing robot unto me can (or should) be considered overt, blatant or aggressive. The caveat is that any robot in possession of a trackball and in its home stretch can be considered to be "hurdling," and contact with them or their ball as such is a very bad thing.

In circumstances, however, where we're defending from behind their finish line and, as I suspect many teams will, they've released the ball to complete the hurdle -- that team no longer satisfies the conditions of HURDLING -- and, moreso, we are really doing nothing more than HERDING at a height of 7 feet. I can't imagine how a wall, sitting innocently on one side of the overpass and bouncing balls away, is doing anything wrong. :)
You did just wake up. You're IMPEDING across the entire track and have possibly exceeded the 80" cylinder. You have six seconds from the first "let me through" tap before the ref flags start coming out. (There is also the possibility of high contact penalties.)

Assuming you sat there all match, that's 120/6-1=19 possible for impeding, plus 1*#high contact, plus 1 for the 80", maybe including a disable and/or DQ. 20 penalties minimum at 10 points apiece=200 penalty points minimum, not counting high contact.

The purpose of the above math is to help ensure that no one tries this at home or at regionals.

[Madison]

You did just wake up. You're IMPEDING across the entire track and have possibly exceeded the 80" cylinder. You have six seconds from the first "let me through" tap before the ref flags start coming out. (There is also the possibility of high contact penalties.)

Assuming you sat there all match, that's 120/6-1=19 possible for impeding, plus 1*#high contact, plus 1 for the 80", maybe including a disable and/or DQ. 20 penalties minimum at 10 points apiece=200 penalty points minimum, not counting high contact.

The purpose of the above math is to help ensure that no one tries this at home or at regionals.

I'm not suggesting that you block the entire track -- only a portion of it and only above the overpass. My suggestion of a crab drive as an ideal drive train for this is precisely because you'd want to be able to strafe back and forth alongside the overpass since you cannot, obviously, block it all at once.

You are not impeding anyone so long as there's room for them to get by. Our robot's take up only 3' of the available 13', so unless there's a serious mess down below the overpass, it's exceptionally unlikely that you'll genuinely be impeding anyone from getting by. If you bump into me and the field around me is wide open, don't expect me to move anywhere.

[EricH]

I'm not suggesting that you block the entire track -- only a portion of it and only above the overpass. My suggestion of a crab drive as an ideal drive train for this is precisely because you'd want to be able to strafe back and forth alongside the overpass since you cannot, obviously, block it all at once.

You are not impeding anyone so long as there's room for them to get by. Our robot's take up only 3' of the available 13', so unless there's a serious mess down below the overpass, it's exceptionally unlikely that you'll genuinely be impeding anyone from getting by. If you bump into me and the field around me is wide open, don't expect me to move anywhere.You still get an impeding penalty because you are slower than they are and moving to block them. And you may still get high contact penalties.

[Jethr0]

but, unfortunately you can only bump a robot if it is blocking the path of yours sooooo, bumping a hurdling robot only works if they are blocking you.:(

[Madison]

You still get an impeding penalty because you are slower than they are and moving to block them. And you may still get high contact penalties.

<G40> IMPEDING Traffic – ROBOTS shall not intentionally IMPEDE the flow of traffic around the
TRACK. A ROBOT will be considered to be IMPEDING traffic if it is preventing an opposing
ROBOT from proceeding around the TRACK. A ROBOT can be found to be IMPEDING
traffic if:
• the ROBOT is traveling slowly relative to the approaching ROBOT, and moving to
prevent the approaching ROBOT from passing, or
• the ROBOT is stopped on the TRACK and there is no clear lane of passage for the
opposing ROBOT, or
• the ROBOT pins an opposing ROBOT against an arena element, border, or another
ROBOT

It's clear that if you remain stopped as you block their hurdle -- and there is a path around you -- you do not satisfy the second condition of <G40> and are not impeding anything. Moving sideways may constitute an impeding violation if you're very generous about what it means to "prevent the approaching robot from passing." Until they've bumped me, I cannot receive an impeding penalty and if they're attempting to hurdle, they will not bump me.

Again, this makes very little difference to me. There remain a number of rules which, in my opinion, are too reliant on the subjective judgement of a referee.

I can't be impeding a robot intentionally unless I know that it's trying to get by me, and I can't know that until it makes an attempt at such or "bumps to pass". A robot 20' behind me may have every intention of passing me as it catches up to me and I might be weaving back and forth in an unrelated action and there exists every opportunity for a referee to interpret that as impedence. That is unsettling.

[johnr]

as soon as that ball touches your bot ,i think that is a complete hurdle.

[Madison]

as soon as that ball touches your bot ,i think that is a complete hurdle.

Only if the ball has completely passed through the plane of the finish line. If you deflect it backward before then, it hasn't CROSSED the finish line and thus, does not meet the definition of a HURDLE.

[Daniel_LaFleur]

Only if the ball has completely passed through the plane of the finish line. If you deflect it backward before then, it hasn't CROSSED the finish line and thus, does not meet the definition of a HURDLE.

My guess is that you'll not be able to build it strong enough to withstand a strong blow from the ball (remember, some teams will shoot the trackball and it has a decent amount of mass) and if you do build it strong enough then you will be very top heavy and will likely end up on your side, blocking traffic and incurring penalties for the remainder of the match.

[flamefixed]

There isn't anything directly stating that herding your opponents trackball into the "corner" and simply sitting there, having your bot between the ball and everything else, is illegal. Right? Please correct if im wrong. There is still ample room to pass, so no impeding, and the bump rule only is in effect if you are impeding and there is no other lane to pass.

Also a simple bump of the opponents trackball backwards across a line, completely legal as long as they weren't in the process of hurdling? This should be easy due to the balls bounce-ability (yeah, we do that haha) Legal still?

Defense is subtle, but still a very good strategy if your scoring device/strategey is weaker than your TWO alliance teammates, and they are controlling the TWO balls assigned to your alliance.

Anything against the rules here? Or are we still finding decent loopholes

[EricH]

There isn't anything directly stating that herding your opponents trackball into the "corner" and simply sitting there, having your bot between the ball and everything else, is illegal. Right? Please correct if im wrong. There is still ample room to pass, so no impeding, and the bump rule only is in effect if you are impeding and there is no other lane to pass.

Also a simple bump of the opponents trackball backwards across a line, completely legal as long as they weren't in the process of hurdling? This should be easy due to the balls bounce-ability (yeah, we do that haha) Legal still?

Defense is subtle, but still a very good strategy if your scoring device/strategey is weaker than your TWO alliance teammates, and they are controlling the TWO balls assigned to your alliance.

Anything against the rules here? Or are we still finding decent loopholesNothing illegal that I see (though the GDC might make it so, but I can't see them doing that).

[Zyik]

blocking traffic and incurring penalties for the remainder of the match.


<G37> ROBOT to ROBOT Interaction
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.

What I'm getting from this is that if M. Krass's proposed robot did tip for whatever reason, we could gently nudge it out of the way as much as we could, I don't know if you'd be able to help it up again, but gently pushing it to the side appears to be allowed without penalty.

I'm not saying that this rule allows you to continue racing, getting off scott-free if you tore through the toppled robot, but it looks like FIRST knows that a toppled robot is a major hazard to a game like Overdrive.

[Drwurm]

I don't doubt there will be a bit of strategic defense this year. But I dont think it will be anywhere near as satisfying as pushing another team sideways into a wall.

Also, I'd advise against bets with Adam Heard. He tends to pick his battles well.

[AdamHeard]

I don't doubt there will be a bit of strategic defense this year. But I dont think it will be anywhere near as satisfying as pushing another team sideways into a wall.

Also, I'd advise against bets with Adam Heard. He tends to pick his battles well.

Lol, thank you for the compliment.




As for the thread, there obviously won't be the hard hitting and pushing that occured last year, but there will be plenty of incidental contact with 6 robots going around the track that would favor the same kind of drivetrain that is a good defensive robot.

So, no direct defense; but plenty of interaction.

[mateus]

Lol, thank you for the compliment.




As for the thread, there obviously won't be the hard hitting and pushing that occured last year, but there will be plenty of incidental contact with 6 robots going around the track that would favor the same kind of drivetrain that is a good defensive robot.

So, no direct defense; but plenty of interaction.

And there will be more interactions if you think that most of time the robots have only half of the area we used to have...
I believe this year game will benefit intelligent defense, as building a robot only to push others won't be so successfull...

The game is clearing in my mind, and I believe that it will be much better than we expect... All we need to do is think smart... and there will be many different strategies to attack or defense, that you might use without break any rule...

[Branden Ghena]

I didn't get to read this whole thread, so sorry if this has been mentioned.

A simple defense in hybrid mode should be very possible for all teams. They could just place their robot the farthest to the left it can be as a starting position, and then in hybrid mode just drive forward about 5 feet. They would then be blocking the middle of the lanes in perfect placement to stop autonomously controlled robots from continuing around the course.

[Sunshine]

There will be defense but it will be centered around the ball more than the opposing robot. It would be more like soccer, where you should be going after the ball to be legal.

I hope that those working on catapulting are NOT working at aiming those balls at other robots as they hurdle. I hope that FIRST puts a rule in indicating that blatant aiming at robots will be a DQ.

A question for those of you that discuss "strategic defense". Is there any other kind?

[octothorpe]

There remain a number of rules which, in my opinion, are too reliant on the subjective judgement of a referee.

I can't be impeding a robot intentionally unless I know that it's trying to get by me, and I can't know that until it makes an attempt at such or "bumps to pass". A robot 20' behind me may have every intention of passing me as it catches up to me and I might be weaving back and forth in an unrelated action and there exists every opportunity for a referee to interpret that as impedence. That is unsettling.

I have to say that <G40> does seem written to prevent all but either the most original or best-disguised forms of defense. Perhaps this will simply force defensive robots to get more creative; I certainly hope it doesn't eliminate their role. Non-destructive defense is a perfectly legitimate part of the FRC challenge, and as several people have pointed out, just because scoring tends to be more glamorous shouldn't mean that it's the only viable strategy. Besides, one of the characteristics of a good offensive robot should be the versatility necessary to evade and overcome defensive attempts.

[Alan Anderson]

A question for those of you that discuss "strategic defense". Is there any other kind?

The other kind is "tactical defense".

[ScottM]

It might be better to refer to defense as "active" and "passive".

Active defense would involve your robot agressively trying to stop your opponent's offensive moves through some sort of robot to robot interaction that you initiate. The GDC has effectively eliminated most avenues of this type of defense in the rules. (Defense on the trackballs being one exception)

Passive defense would involve trying to stop your opponents by being in their way, without actively initiating robot to robot contact. The rules allow you to be standing still anywhere on the field, as long as you aren't moving and there is a clear lane around you.

One strategy of using a passive defense would be to position your robot in front of your alliance's trackball on the opposing alliance's overpass, which could hinder attempts by your opponents to dislodge it. This is perfectly legal within the current rules, as long as you are not moving to impede the opposing robots.

Personally, due to the nature of this year's game, I would not discount the possibility of a successful passive defensive strategy.

[ALIBI]

There will be defense but it will be centered around the ball more than the opposing robot. It would be more like soccer, where you should be going after the ball to be legal.

I hope that those working on catapulting are NOT working at aiming those balls at other robots as they hurdle. I hope that FIRST puts a rule in indicating that blatant aiming at robots will be a DQ.

A question for those of you that discuss "strategic defense". Is there any other kind?

The manual indicates that you should design your robot to withstand hits from Trackballs! Intentionally trying to damage or tip an opposing alliances robot is a no no. If a hurdler obviously moves their robot/hurdling mechanism back and forth to aim at another robot it would probably be a rules violation. A new rule is probably not needed, however, an interpretation of the applicable rules will either be asked about in the Q and A or be a topic of discussion during the drivers meeting with the Head Ref. A hurdler should not have to look down the field to see what may be in the way of the Trackball once he hurdles it. My advice, if you see a a Trackball coming, get out of the way! Even if it is a rules violation it would not be worthwhile to be tipped over or worse damaged just to have the opposing alliance get a penalty.

[65_Xero_Huskie]

Trust me, If you think that there will be no defense this year, you are mistaken.
THis game is designed so that defense is going to be played at the same time as offense. Robots the are just boxes on wheels are going to be effective and i figure that they will be able to make or break a match in qualifying. There are teams that will make a strategy to play defense and be VERY effective.

[Zyik]

Trust me, If you think that there will be no defense this year, you are mistaken.
THis game is designed so that defense is going to be played at the same time as offense. Robots the are just boxes on wheels are going to be effective and i figure that they will be able to make or break a match in qualifying. There are teams that will make a strategy to play defense and be VERY effective.

Thankfully FIRST made it so that this year a box on wheels can still score. This should encourage rookie teams who don't have the know-how/experience/resources to build a more complex robot.

If you have a robot that takes a while to pick up a trackball an opposing robot, say... a box on wheels... could "bump to pass" just enough to make them have to realign themselves again, while the box on wheels keeps going around the track, scoring points. Hopefully the robot doesn't take to long to position them selves and grab the trackball or the box on wheels could keep this up the whole match, while scoring points for their alliance.

[Sunshine]

Defense now becomes much more challenging after Update 2

[IbleedPink233]

Defense now becomes much more challenging after Update 2
I don't see how it is harder, unless you planned on aggressively attacking your opponents' Trackball while they were Hurdling.

Our team has discussed defense and I think that the rules have been laid out to encourage teamwork (sharing balls with your allies) and discourage heavy defense (an improvement over last year, where slamming a robot into the Rack, often entangling it, was just fine - I never saw it called).
Defnitely, the defense this year will be way more creative this year than last year, where the push-the-robot-halfway-across-the-field-and-never-stop strategy was the one that was the only truely effective one (at least, the only widely used effective one).
In my brief experience as a base driver during off-seasons, it is way more fun to play effective defense than it is to score because it is a mental challenge between you and your opponent.
We will have to see how the game turns out - as it could be in any number of ways, but I definitely foresee a copious amount of defense (you have to have at least one ally without a Trackball do something) even if it is not really intense. A lot also rests in the hands of the Referees, of course.

[AdamHeard]

If you try this approach, you may need a few extra team members to help you count all your penalty points. There are a few rules that very effectively combine to prevent you from doing this.

-dave


Just curious, as this confused me, what rules does it break? I can't seem to find any that are violated, but you are Dave Lavery after all; I kind of trust you :cool: .

[hipsterjr]

I think it would be wise to watch some NASCAR races. There is more than just "turning left" going on there. If alliance partners work closely together, they can effectively create a three (or just two) wide moving wall. While opponents can keep moving, they are seriously slowed down/aggravated, and getting TB's becomes a nightmare. This strategy, employed with "the dance" (mentioned by others as a offense strategy) would throw a beautiful defense/offense combo into the mix:D

In summary, this year, good defense will come from team work. Not just one or two ambling bash and run bots.

[thefro526]

I think it would be wise to watch some NASCAR races. There is more than just "turning left" going on there. If alliance partners work closely together, they can effectively create a three (or just two) wide moving wall. While opponents can keep moving, they are seriously slowed down/aggravated, and getting TB's becomes a nightmare. This strategy, employed with "the dance" (mentioned by others as a offense strategy) would throw a beautiful defense/offense combo into the mix

In summary, this year, good defense will come from team work. Not just one or two ambling bash and run bots.

I think this would be a very interesting strategy. It would be especially useful for an alliance of non-hurdlers to use against hurdlers. Over time many drivers would become frustrated and more inclined to mess up.

[Spiders]

heres a semi-stupid question :P are you allowed to pick up the opposing teams ball and launch it backwards?:ahh:

[EricH]

heres a semi-stupid question :P are you allowed to pick up the opposing teams ball and launch it backwards?:ahh:That's possession, so no.

You may, however, simply knock it backwards.

[bduddy]

My guess is that you'll not be able to build it strong enough to withstand a strong blow from the ball (remember, some teams will shoot the trackball and it has a decent amount of mass) and if you do build it strong enough then you will be very top heavy and will likely end up on your side, blocking traffic and incurring penalties for the remainder of the match. Remember that if you end up on your side, you can disable your robot and then not incur any penalties... hmm... is anyone planning that? :eek:

(note: I know it's not GP and we're certainly not planning it... don't do it... bad...)

[Steve W]

I believe that I saw some of the best defence played this week at FLR. The team that did a fantastic job happened to be on the winning alliance. Team 2053 played the part perfectly shutting down some great robots on the way to victory. They were so good that their opponents got penalties trying to play around them. If and when videos become available watch the elimination rounds and especially the matches that Moe played against 2053.

Defence is not only alive but is thriving.

[Jeff Rodriguez]

I believe that I saw some of the best defence played this week at FLR. The team that did a fantastic job happened to be on the winning alliance. Team 2053 played the part perfectly shutting down some great robots on the way to victory. They were so good that their opponents got penalties trying to play around them. If and when videos become available watch the elimination rounds and especially the matches that Moe played against 2053.

Defence is not only alive but is thriving.

For those of us who haven't seen matches from FLR,could we get an explanation of what they did and why it worked so well?

[David Brinza]

Starting Friday afternoon in San Diego, we employed some stiff defense. We were warned by the head ref that some teams felt we were being too aggressive. We made a very conscious effort to avoid contacting robots in the act of hurdling, we would move within 4 seconds of impeding and secured our gripper arms so they could not make contact outside of an opponent's bumper zone.

We were correctly issued a "yellow card" for a high-speed ram against our friends (Team 968) in our final qualification match - our driver was simply too late in backing off the stick. Otherwise, we had no penalties associated with playing some rather tenacious defense.

Without defense, this game will become an exhibition and will lose a lot of the excitement.

[s_forbes]

Carl Hayden (842) played some amazing defense on the almost unbeatable 39 robot in AZ. It was a combination of depriving them of the ball and 'irritating' them on their way around the track. They almost beat them in the first semi final match, but the 39/60/1165 combination was able to pull off a win.

[tennispro9911]

Defense is going to be a huge part of the game. I'm the driver for 2053 and we basically took away one of the balls for the other team by preventing them from getting to it. We frustrated MOE and some other very very good teams. MOE was consistently getting 5 or 6 hurdles each match and I fully expect them to win a regional and be a force at Championships.

[hipsterjr]

At Florida, in a few matches we played heavy defense (getting in between balls, pushing bots they were not hurdling, impeding for less than 5 sec) and it worked great. The only problem is that the refs frowned heavily on this. We were warned several times that "overdrive is and offense game." Was it like this at other regionals?

[Madison]

At Florida, in a few matches we played heavy defense (getting in between balls, pushing bots they were not hurdling, impeding for less than 5 sec) and it worked great. The only problem is that the refs frowned heavily on this. We were warned several times that "overdrive is and offense game." Was it like this at other regionals?

Who was it that "warned" you, out of curiousity?

[Travis Hoffman]

At Florida, in a few matches we played heavy defense (getting in between balls, pushing bots they were not hurdling, impeding for less than 5 sec) and it worked great. The only problem is that the refs frowned heavily on this. We were warned several times that "overdrive is and offense game." Was it like this at other regionals?

In the future, I would show any who possess such mentality the following GDC response:

http://forums.usfirst.org/showthread.php?t=9019

"FIRST Overdrive has never been defined as an "all-offense, no-defense game." Defensive strategies, used appropriately, are perfectly acceptable."

Straight from the horses' mouths. If you play it within the rules, especially the opponent trackball manipulation, then go for it.

[EricH]

At Florida, in a few matches we played heavy defense (getting in between balls, pushing bots they were not hurdling, impeding for less than 5 sec) and it worked great. The only problem is that the refs frowned heavily on this. We were warned several times that "overdrive is and offense game." Was it like this at other regionals?Somebody tell team 8 that! In SVR finals, they played legal (mostly) defense.

[danshaffer]

Somebody tell team 8 that! In SVR finals, they played legal (mostly) defense.

"Ball denial" (as we're calling it now) was discussed at length between our drivers and rule lawyers and the head ref at SVR. Some of the illegal contact (for which we were penalized) occurred because it was behind the glass and so our drivers could not see where our robot or other robots were. The head ref understood this issue, but merely suggested that we send our robocoach to the other end of the field to mitigate this issue... not exactly an ideal solution.

[octothorpe]

they played legal (mostly) defense.

Mostly is right. I like the defensive action in this year's game and I think Paly did a great job of taking that on, but during the second match of the SVR finals in particular I definitely saw some uncalled possession of the opposing alliance's trackball (i.e. trackball resting on their robot's arm).

[Josh Fox]

Defense is definitely alive and well in Overdrive. Just because it's not as obvious as in previous years, a good defensive player can truly alter the outcome of a game.

Things like movement of an opponent's ball, and even pausing for a second while in front of a team's robot can usually take their score down by at least a hurdle due to the time it takes to control these giant trackballs, and by the amount of time you can delay a team. Sure, you may not be blocking a ringer, but it's all of the subtle delays that can truly impact this year's game.

In my opinion anyway.:cool:

[David Brinza]

It seems some teams have an adverse reaction to those teams that choose to employ defensive tactics. Right up until alliance selection occurs when they rather have those defensive teams with their alliance rather than against!

I've said this before and still believe it to be true: without defense, FRC becomes an robot exhibition rather than a game. Effective defense places a premium on robot speed & maneuverability, driver skill, situational awareness, scouting and coordination with alliance partners. BTW, defensive robots can still rack up scores for their alliance: knocking down balls and crossing lines in hybrid mode; clicking off a few laps and herding/feeding Trackballs to hurdling partners during tele-operated play.

[hipsterjr]

Who was it that "warned" you, out of curiousity?

the refs

[Guy Davidson]

Mostly is right. I like the defensive action in this year's game and I think Paly did a great job of taking that on, but during the second match of the SVR finals in particular I definitely saw some uncalled possession of the opposing alliance's trackball (i.e. trackball resting on their robot's arm).

The referees were only calling it when it was clearly intentional. If not, then I would be confused as to how it wasn't called during match number three, or its replay, where a blue trackball was sitting on their robot.

Regardless, we played defense as allowed be the rules as the refs were calling them. Our ball denial strategy was deemed perfectly legal by ourselves and the referees (assuming, of course, there is a lane around us, otherwise we're impeding). We believe Overdrive to be just like any other FIRST challenge from recent years: there are rules. Whatever you can do, that is legal according to the rules, is fair game. We play hard, but we play fair.

[The Lucas]

The referees were only calling it when it was clearly intentional.

If you are intentionally playing defense on a ball and you posses it, even if it is accidental, it should be a penalty. <G29> doesn't specify intent. The only time it shouldn't be a penalty is when it is when it is caused by an opponent as per <G23> (like when a hurdled ball fall into a shooter bot).

I am not talking about any specific match example but just the rule in general. Trackball defense is legal and a good strategy in many cases. However, if the unintended side effects of a team's trackball defense is trackball possession then it is clearly a penalty and that team is responsible.

[XaulZan11]

After watching a fair amount of the regionals, I'm disapointed with the lack of 'traditional' defense found in the past two years. Instead of pushing the opposing alliance, teams are trying to get too cute with ball defense and thus not as effective. I think many teams are under the impression that 'defense is illegal', while its clearly not. Yes, there are some stricter rules (such as no defense on a robot in the act of hurdling--but how is that different from playing defense in the opponents homezone like last year?), but teams can still do many of the strategies and tactics that were super effective the past two years.

For example, why don't more teams push the opposing alliance while they are picking up the ball or moving around the track (not in thier homestrech)? Or, why don't more teams pin the other teams against the wall for 5 seconds (again, not while they are attempting to hurdler)? According to <G41>, "When a ROBOT has received a signal to pass (see Rule <G38>), or when the REFEREE signals that a ROBOT is pinning an opponent in place, the ROBOT shall have 6 seconds to move out of the way and create a “passing lane” to allow the opposing ROBOT through." I don't see why a team couldn't pin a team against the wall for 5 seconds, let them pass and move to the next quadrent, pin them again, and so on.

I know some may feel this is 'against the intent of the rules'. I feel that as long as the rules don't prohibit the action, its a viable strategy. Unless you are part of the game creators, you cannont know the full intent of the rules.

[Rick TYler]

why don't more teams pin the other teams against the wall for 5 seconds (again, not while they are attempting to hurdler)? According to <G41>, "When a ROBOT has received a signal to pass (see Rule <G38>), or when the REFEREE signals that a ROBOT is pinning an opponent in place, the ROBOT shall have 6 seconds to move out of the way and create a “passing lane” to allow the opposing ROBOT through."

I don't think you can do repeated pinning this year. You didn't quote all of that rule:

<G41> Permitting To Pass - When a ROBOT has received a signal to pass (see Rule <G38>), or when the REFEREE signals that a ROBOT is pinning an opponent in place, the ROBOT shall have 6 seconds to move out of the way and create a “passing lane” to allow the opposing ROBOT through. ROBOTS that fail to do so within 6 seconds after the “signal to pass” shall receive a PENALTY. Repeated infractions will result in a YELLOW CARD being issued to the ROBOT.

It looks to me like if you keep pinning OR refusing to give way you can be yellow carded and ultimately DQ'd. That's a pretty big risk just to slow someone down.

[XaulZan11]

I don't think you can do repeated pinning this year.

It looks to me like if you keep pinning OR refusing to give way you can be yellow carded and ultimately DQ'd. That's a pretty big risk just to slow someone down.

Yes, I see what you mean, but I think what it means by 'repeat infractions' is repeat penalities, NOT repeat pinnings. Thus, you can pin someone for 5 seconds, not get a penalty and repeat. Anyone else agree with me or am I just reading the rules the wrong way?

[Rick TYler]

Yes, I see what you mean, but I think what it means by 'repeat infractions' is repeat penalities, NOT repeat pinnings. Thus, you can pin someone for 5 seconds, not get a penalty and repeat. Anyone else agree with me or am I just reading the rules the wrong way?

Ah, now I understand. You pin, then watch the ref counting, and just before they get to "6" you let the pinned robot go. So, you never commit a penalty at all. It could work, but you would need to have really good control to not step over that six second barrier. I think you are right now that I've thought about what you meant.

[Alan Anderson]

...Thus, you can pin someone for 5 seconds, not get a penalty and repeat. Anyone else agree with me or am I just reading the rules the wrong way?

I think you're reading the rules the wrong way. Specifically look at this phrase: ...the ROBOT shall have 6 seconds to move out of the way and create a “passing lane” to allow the opposing ROBOT through.
If you move out of the way for just a moment and then repeat the pin, you haven't satisfied the requirement that you "allow the opposing ROBOT through."

[Joe Ross]

The following new Q/A answer has some important insight: http://forums.usfirst.org/showthread.php?p=16357#post16357

[XaulZan11]

If you move out of the way for just a moment and then repeat the pin, you haven't satisfied the requirement that you "allow the opposing ROBOT through."

You may be right. I was thinking of something like pinning the robot right after they hurdler and cross the finish line for five seconds, let them pass, then pin them for five more seconds in the next quadrent.

I'm not sure if this is the same as the example in the Q&A. In that example, the robot is not given the chance to use the passing lane and progress around the track. In my example, however, the pinning robot lets them move foward to the next quadrent or a good portion of the track before the next pin takes place.

[brentmcjunkin]

whoever said there is no defence this year is stupid there are actually some good defecive teams out there

[SL8]

whoever said there is no defence this year is stupid there are actually some good defecive teams out there

Please do not insult or attack people in your post. The"whoever said there is no defence this year is stupid " was completely unnecesary. And Good syntax does help convey your message.

Yes, there are good "defective" robots out there, but then, they are no longer so defective.

[jayjaywalker3]

Did anyone see the defense in the elimination rounds at the NYC regional? The semifinal matches in particular (the ones with team 694). They were amazingly aggressive and were not flagged at all in the first match and not very much in the third match.