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Chris is me 21-03-2010 14:28

Re: Defense?
 
Quote:

Originally Posted by BJC (Post 940391)
I think that when it comes to defense this year teams don't want to play it because they feel their ability would be better used elsewhere.

As a result I have yet to see a robot who consistantly plays good defense in the far zone AND can clear balls to the other side of the field.

Watch 1625 in Kansas City.

BJC 21-03-2010 15:07

Re: Defense?
 
Quote:

Originally Posted by Chris is me (Post 940393)
Watch 1625 in Kansas City.

Ya, I'm sure that there are robots that do it, its just that I have yet to see them.

Anyways, I'm sure that 1625's got the right idea. ;)

However, I would like to see more teams do this.

Also, this would be really when playing against a 469 or 51 type robot.
(we're playing 469 this weekend; we'll probably end up doing something very similar to this.

NOV8R 21-03-2010 15:13

Re: Defense?
 
The winning strategy in the regional finals I've seen have bee based on the saying " the best defense is an aggressive ofense". During autonomous if an alliance can get balls downfield and score a few in the process, the far end robot leaves the zone during the start of teleoperated leaving no defender in that zone. Once in the mid-field the best herder/near zone kicker moves to the near zone ganging up on the lone defender. The mid-fielder keeps shooting and scoring balls as well. This strategy seems hard to defend against.

XaulZan11 21-03-2010 15:33

Re: Defense?
 
Quote:

Originally Posted by Chris is me (Post 940393)
Watch 1625 in Kansas City.

111 has also played mostly in the 3rd zone for a significant amount of their elimination matches in both Wisconsin and Midwest. I think it is worth noting that in 3 regionals 1625 and 111 have done this, they have yet to win and have 1 finalist. (obviously that is not a knock on them, just an observation of the strategy). Has their been a top robot play in the 3rd zone most of the time and win?

I think the key is flexibility. If you have robots that can only play in one zone or do the same strategy, you will be predictable and probably beaten.

BX HANNAH 21-03-2010 15:54

Re: Defense?
 
Quote:

Originally Posted by Alex Dinsmoor (Post 940342)
I completely agree with that!

Scouting on Saturday, it was obvious that teams were trying to show off their specialties so they could look good for picking. What I learned though, is that the best teams do what they do best for the entire competition. Take 1023 for example; they were playing amazing defense all weekend, and look at how that turned out :)

At Detroit, the effectiveness of defense in the elims was variable. There were teams who used defense to their advantage to help shut down other robots, but there were also the matches where teams would score the heck out of their goals and produce scores such as 13-13 or even 14-13.

It all depends on the alliance and who they are playing against. What we learned in the finals matches is that if someone is going up to hang before the finale to say redirect balls (51 ;) ) It would be best to play defense against them hanging rather than just trying to block goals up close.

Thank you very much! :)

kjolana1124 21-03-2010 16:00

Re: Defense?
 
Quote:

Originally Posted by NOV8R (Post 940421)
The winning strategy in the regional finals I've seen have bee based on the saying " the best defense is an aggressive ofense". During autonomous if an alliance can get balls downfield and score a few in the process, the far end robot leaves the zone during the start of teleoperated leaving no defender in that zone. Once in the mid-field the best herder/near zone kicker moves to the near zone ganging up on the lone defender. The mid-fielder keeps shooting and scoring balls as well. This strategy seems hard to defend against.


While I agree with you, I can't help but feel like it's relying a bit too much on autonomous. Having a defender in the close zone at least makes it harder to score, even if they do allow balls though. Robots who are in the mid-field will have to have to be able to boast the ability to transport balls to their scoring zone quickly and effectively in order to keep the edge on their side. Not only that, but they also have to keep balls away from the other mid player. Having a defender bot takes a way a little bit of that pressure of the mid-fielder; yes they have to get balls over the bump, but at least this way it's a little harder for the other to score.

BJC 21-03-2010 17:02

Re: Defense?
 
Quote:

Originally Posted by NOV8R (Post 940421)
The winning strategy in the regional finals I've seen have bee based on the saying " the best defense is an aggressive ofense". During autonomous if an alliance can get balls downfield and score a few in the process, the far end robot leaves the zone during the start of teleoperated leaving no defender in that zone. Once in the mid-field the best herder/near zone kicker moves to the near zone ganging up on the lone defender. The mid-fielder keeps shooting and scoring balls as well. This strategy seems hard to defend against.

I have noticed this too. However, I have also noticed that because of the lack of this stratigy balls that go into the near or far zone rarly come out execpt through the ball return (scoring). Therefore, a stratigy that involves being able to clear balls from the far zone has some merit.

Have you noticed how many balls are actully down there after the auto. In elims I'd say around 4ish. If you even just clear that 4 before going to the middle thats 4 balls your opponent doesn't have that they normally would (and 4 balls you do now have;) ).

There is definatly something to this idea although I don't think you can win by just keeping the "best" robot on your alliance down there all match.

NOV8R 21-03-2010 17:12

Re: Defense?
 
BJC...I agree with you. If balls are not kicked out of the far zone in auto you'd better hang around briefly in tele to do it. Your opposition can't score balls they don't have. The mid-field is the key to the game in teleoperated. Even if you don't have a looper you need to have a mid-field robot that can aquire and kick them quickly when they come off the rail. An ample supply of balls and two robots in the near zone overwhelms the lone defender.

Chris is me 21-03-2010 18:10

Re: Defense?
 
The simplest explanation for any strategy for any alliance: Go where the balls are and fight for them. An alliance that can't effectively do this doesn't win. An alliance that locks all the balls up in the protected zone inherently wins.

BJC 21-03-2010 18:13

Re: Defense?
 
Quote:

Originally Posted by Chris is me (Post 940542)
The simplest explanation for any strategy for any alliance: Go where the balls are and fight for them. An alliance that can't effectively do this doesn't win. An alliance that locks all the balls up in the protected zone inherently wins.

Which makes the auto key for any alliance. You know where exactly half of the balls on the field are and can shoot them without being hindered. Thats more than the final score for most matches:ahh: .

RRLedford 24-03-2010 19:04

Re: Defense?
 
We were chosen to be with 111 and 1625 in the Midwest Regional.
Being a small rookie team (but at least with 4 seniors who had been on cooperative teams before), we attempted to do a way more complicated build than we had man power to handle. When our robot shipped, it had only one feature working and tested - a stellar drive. The remainder of our bot parts were all brought to competition, and many were not even fitting correctly, since we had no CAD record of the build, and measurements were spotty at best. Day1 was a nightmare of problem solving and we made no practice matches. We barely passed inspection at the end of the day, and our variable winder kicker was getting a mandatory weight reducing makeover.
At that point we still had nothing working but our short wheelbase (18') tank drive :
(2) Dual CIMed Super shifters gearboxes w/ pneumatic shift (sometimes)
(4) 8" dia. chain driven, Plaction wheels with Roughtop tread
We were also right up against the 120 lb limit.

We began the Day 2 qualification matches able to do little more than push balls poorly and defend. As our driver learned to drive, he soon found that the added weight of penumatics & kick winder toughbox has imbalanced the bot so much it no longer traversed the hump.
As we made the best of what we had, it soon became clear we had a super fast, powerful, very maneuverable, high traction tank driven bot. This allowed us to nearly even keep up with the more nimble swerves and mecanums when going for balls and position on the floor, and once we quickly arrived, we could push and disrupt pretty much all these more advanced drive bots at will.

As the day progressed we became quite good at defense, since there wasn't much else we could accomplish, but this only placed us in the high 20's (of 42) in the standings at end of 2nd Day. With two more qualifying matches to complete on AM Sat, we were not expecting to make the elimination round. We concentrated on getting our winder & ball handler ready for the upcoming Northstar Regional. So far, we had missed no qualification matches, and we made the last two on Sat AM as well, scoring enough to move up into the lower 20's in the standings.

We soon found out we had been picked to be with a 111 and 1625 alliance! How could we decline this? Clearly our defensive prowess had registered with at least these two powerhouse teams. We scrambled to eliminate any penalty producing problems and to upgrade our ball pushing accuracy. Kicker remained too risky to activate. We then squeaked into the semi-finals carried mainly by 111's autonomous kicking of 3 balls from the far zone, but all 3 alliance members started developing bot problems. Near the end of our last match of the semi's, chain issues doomed our chances, taking out both our bot, and 1625 as well.

So, I advise all teams out there whose abilities are mainly in the defensive column, sharpen them up and go with them. They can carry you further than you might expect. We will continue to wreak some defensive havoc in Minneapolis, and even with a working full field kicking winder clearing 3 balls in autonomous, plus some decent ball handling, we will still keep focused our defense all the way to the finals there. BTW, we did win the Rookie All Star award at Midwest Regional.
-Dick Ledford

45Auto 25-03-2010 08:18

Re: Defense?
 
Quote:

Originally Posted by RRLedford
When our robot shipped, it had only one feature working and tested - a stellar drive. The remainder of our bot parts were all brought to competition, and many were not even fitting correctly, since we had no CAD record of the build, and measurements were spotty at best. Day1 was a nightmare of problem solving and we made no practice matches. We barely passed inspection at the end of the day, and our variable winder kicker was getting a mandatory weight reducing makeover.
At that point we still had nothing working but our short wheelbase (18') tank drive

Quote:

Originally Posted by RRLedford (on a different thread)
Even though we had considered loopers to be an ultimate strategy, and one we were capable of implementing effectively

You really think it would be easier to build a looper than a simple kicker? Sounds like it was a good thing you guys didn't try to build a looper, given all the problems you had with the kicking bot.

Glad it all worked out for you in the end!

RRLedford 25-03-2010 15:06

Re: Defense?
 
Quote:

Originally Posted by 45Auto (Post 943013)
Sounds like it was a good thing you guys didn't try to build a looper, given all the problems you had with the basic simple kicking bot.

Glad it all worked out for you in the end!

A Gravity fed ball chute scheme with a pneumatic left-right flipper would have been much easier for us to handle combined with tower latching. We may not have reached the 469 level of loopiness, but it would have been looping balls on Day 2.
Our variable kick winder was well designed and built mechanically (except in the weight category), but a combination of going overweight, two encoder failures, and two pneumatic valve failures did us in with it at our first regional. Though we could operate enough for a basic kick by the semifinals, with it being untested in match play at that stage, we had no practice and no confidence that we could avoid a nasty penalty of protruding past frame for more than two seconds. So, we didn't fire, but, thanks to having the two powerhouse partners of 111 and 1625, we did reach our best scoring at 3 push-them-in goals with no penalties, while playing some serious defense too..
By the end of Northstar qualifications, we are expecting to have accomplished our design goal of autonomous 3-ball kicking from far zone to goal area => on the fly.
-Dick Ledford

Bjenks548 25-03-2010 19:01

Re: Defense?
 
I have a different strategy that I think is the best solution to elimination matches. First is the alliance captain, from what I've seen this tends to be a mid zone robot that can traverse the bump and score consistently from the mid zone. The first pick should be a loop bot (if there are any left), the loop bot will hopefully be one that can score. In my opinion, most robots can play in the front zone and score. The second pick should be the strongest front zone robot left, however there is also one huge quality that I think will come to play in this next week to look for in the third alliance choose. Blocking a loop bot. Chances are that the alliance will have to play against another loop bot. If your alliance has a robot that can block this or play first zone fairly well, you are prepared for both situations. I’m sure that many more loop bots will start appearing but there will also be a lot more loop blockers. So in this, the only defense that should be played in eliminations is to block a loop bot.

Terror Drone 27-03-2010 19:45

Re: Defense?
 
We have also centered on defense for the Waterloo regional. As much as their were a few teams that were defensive, we had a good center of gravity and many other factors that contributed to it. But the main factor besides that is you can take out a major scoring advantage for the other team with defense, it got us noticed and gave us good rankings. That finished in us becoming an alliance Capitan, so if your alliance has 2 bots that are not specific on stopping scoring attempts defense is defiantly vital to keep the other alliance's score down. Along with being able to get any balls out of the other alliance's zone when available, to avoid them having so many balls that the defense is unable to stop them.


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