Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

This definitely highlights the reliable autonomous over the high risk-high reward. Especially in Rebound Rumble where there was only a 1pt difference between the high and middle goals, I was surprised to see fewer teams go for the middle when the top accuracy just wasn't there.

After Friday at Sacramento, 971 was not nearly reliable enough in the high goal, so we switched to a mid-goal shot in auto, and went from <30% going in to >75% accuracy. We kept this through Sacramento and SVR.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Some of the better auto modes in 2012 were ones that shamelessly drove straight to the middle goal and vomited the balls, but the elite few could obviously hit >3 in the top goal almost every time.

However, some could easily argue that the targets resting on a plane perpendicular to the ground like 2006 and 2013 is easier than shooting into ones parallel from the ground. It's up to teams who test and collect their own data.
But isn't it always?

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Yup ;)

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

So, we wanted to take some time to get to know some of the awesome teams out there, thanks @Team3313 for being awesome http://twentyfour.ewcp.org/post/4136...3-mechatronics

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

This was awesome! Thank you to TwentyFour and Andrew for inviting our team to be interviewed.

The TwentyFour blog has been a constant discussion piece for our team this year and we genuinely appreciate the advice and statistical analysis of it.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

When you have a hammer all problems look like a nail, when you have a plow ramming looks good… Play smart defense! http://twentyfour.ewcp.org/post/4195...ce-an-anecdote

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Great blog, guys -- I hadn't seen it before!

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Defense is a terribly underserved, underdiscussed, and underdeveloped strategy. I would like to see further discussion on the merits and types of defense more than "it's not just ramming."

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

I have to say your info on the 2006 finals is quite wrong.

Although 25 had a low shooter you have to look at where the ball actually exited their frame perimeter. The trajectory was hard to block without a full 60" tall robot.

Also on the Newton alliance that year 25 was the decoy. 968 was actually the high scoring robot through out elims. If you took them out of play 25s cross field loading time limited the damage they could do against 2 or three solid shooters. For a good example of what I'm talking about watch the Newton vs. Galileo match 1 (Einstien QF1-1). That was unfortunately the only of the 3 matches in that series where we had 3 functional robots for the full match.

Also when it comes to undefeated streaks I believe that the only team to win the championship while undefeated at the championship event was 111 in 2009. Prior to that no team had made it past 14-0 before drawing a loss.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Playing piece denial, area denial, drawing penalties... There's a lot more to defense than just pushing and ramming, though some years it's well harder (and harder to parse) than others!

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Thanks Peter, I doubt anyone can tell it better than someone that was there! We'll append/edit it as soon as one of us gets a chance. I still think 2006 is a great lesson in bad defense, as a halfway decent rampcamper the only team that just sat under the goal and rendered us completely useless was 67. We had plenty of people ramming us once we were already under the goal and firing though...

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

I think 2006 can also be a lesson in great defense. It just all depends on the teams involved. I recall more than one occassion where strong defensive play determined the course of a match. In fact, it was strong defense (and a preference towards human loading) that caused 1114, 1503, and 1680 to re-evaluate their loading strategies before IRI. Many of the more adept defenders were successful at trapping teams like 25 and the triplets into the corners beside the ramp while they human loaded. 25's freakish drivetrain and aggressive driving would help them get free of the trap, but it would eat plenty of time off the clock. The Simbots began loading up from the corner of the ramp, to give them an escape route, at IRI.

With ever changing games, defense is an ever changing subject. Different strategies and tactics work in each game, and even change dramatically based on what robots are involved. In some games, ramming can be particularly effective (if often was in 2006, assuming you weren't playing against a triplet). In others, it's pratically useless. Some games, "starvation" strategies can crush an opposing alliances' score (2009 being the best example). In 2006, on the other hand, it was essentially impossible to starve the other alliance of balls and still win the match.

As a general rule of thumb, getting to where the offensive robot needs to be before they get there is usually a pretty good defensive strategy.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

I have thought a lot about defense, particularly in contrast with other sports where in order to field a full team, you must perform on the offensive and defensive side of the ball.

The problem is FIRST games aren't always designed to allow for heavy defense. Low scoring matches are just plain boring. Penalties are assessed for egregious behavior, and defense tends to aggravate students that spent 6 weeks to see their robot throw a frisbee in the goal. You can say "they should have designed for that," but really, should they have to? (PM me if you would like to speak on this in particular). I think that's why the last two years have had "safety zones" to shoot from.

The article still makes a valid point, which is that when defense is played, it is often played pretty poorly, with penalties galore. Just get between your opponent and their destination, even with mecanums. Time is the enemy, and having to push your robot out of the way is the best way to prevent points from being scored.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

Oddly enough, a well driven mecanum can play very effective defense. (Oh Chris is gonna hate me for saying that) High caliber drivers often have a flow to their driving. If you can force them to break that flow, even for a second or two, you've reduced their performance. The practical impact of this is difficult to measure due to there being more variables but the goal should be breaking flow and pattern. The best defense is disruptive and forces your opponents to change their game plan while executing it.

Re: [EWCP] Presents TwentyFour -- An FRC Statistics Blog
 

A defense discussion is definitely merited here. Pushing is often not super effective defense, but what is?

Lets break it down to functional goals. What is the point of defense? To prevent the other team from doing the action that it wants to do (usually scoring). Sometimes this means keeping them away from a certain part of the field, sometimes it means preventing them from lining up. So lets turn that goal around to "What do we want them to be doing", and the answer pops out quite plainly: Anything else. Any time that they spend not doing what they want to be doing is wasted time. Any way that you can get them to do this is good defense.

A great example is from Einstein Semifinals in 2007. 190 was assigned to try to score a few tubes and then play defense on RAGE 173, leaving 987 as our primary tube scorer. At one point, RAGE and 190 both have a tube in their grippers, and RAGE turns away from the rack and pushes 190 halfway across the field. 190 chose not to push back, because our goal was to prevent them from scoring. Any time they chose to spend pushing us around was just as good as getting in their way.

Andrew is spot on that a well driven mecanum can easily be a great defense robot, simply by getting in the way or being disruptive. High speed is also very helpful when defending, often more-so than pushing power. If you can get there before they do, then you have the advantage.Team 71 at Smokey Mountain Regional finals in 2011 drive their fast swerve in one of the best defensive performances I have ever seen, almost single-handedly shutting down their opponents.