So at the start of last season, my team discussed a lot of possibilities about what could happen in a match, including what we wouldn’t be able to defend against…

Note the picture, which has stacks of tubes on movable goals underneath the ladder… Something we saw quite a bit of at Worlds, especially in the finals…

So my question is this: Did anybody else see this coming? How do y’all strategize, and how do you figure out what the winning teams will be doing?

Personally, I usually think about what I would do with the game objects. Regardless of a robot design, I try to think where I want all the objects to end up, (both colors) and then think about how other teams will make that happen, and how I can best keep them from scoring, while insuring that I score…

Any one else have some radical approach they wish to share?

i wonder it the game design committee predicted this!

ill post back soon with all the strategies we came up with!
it helped us win 8/9 matches with the only loss caused by a disconnected alliance :frowning:

I predicted this back in July. In fact I suggested it as a possible strategy, but I forgot about the strategy until I found the wave (we use Google Wave for team collaboration) in which I wrote it a couple months ago. Kind of a shame given that it was the winning strategy haha.

Thats a good approach. For the Gateway:

  1. I want to be the first/bottom in every circular goal, or at least a majority of goals.
  2. I want all my objects scored.
  3. I want the tallest circular goal to be mostly my objects with room for one below the top at the time for doublers.
    I haven’t thought through the end game enough.

For Roundup, I made a perl script to evaluate the score for every possible ending position of all the Red objects, and for each of those, all possible minimum positions of Blue objects that would beat that score.
It was helpful to show the relative values of hanging, and of sequestering tubes.

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I didn’t foresee goal hoarding coming into play at all. I thought the goals would be too hard to grip reliably.

I thought - and still think - that a well executed tube-hoarding strategy could have swept Worlds with a dedicated robot that had other means of scoring (i.e. it could high hang).

Are you doing it again, or is it too much coding for the benefit of knowing every possible game?

there were lots of good bucket bots (team 40) that were capable of high hanging
i think the strategy wasnt the winning strategy was because

  1. they didnt score any of their own tubes (fast enough)
  2. there’s too many tubes to collect (esp when everything is knocked down)
  3. there are counter strategies for hording (base in ladder/ reverse hoarding)

i think team 254a came up with a reverse strategy to counter green eggs
too bad it wasnt as efficient as i would have thought…

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A good basket would do this in autonomous mode.

254A had planned and experimented with their robot well before 44’s design was outed in early 2011. It was built primarily to counter the “rings under the ladder” strategy widely used at Pan-Pacific Championships (and several other tournaments as well).

While reviewing the match recording for SF1-1, we found that the deciding factor was actually autonomous mode - because 254A didn’t curl left into 1492Z’s goal (as was planned), the point swing made the difference between a 15-point Blue win (8 if 44 had descored the final blue tube) and a 5-point Red win. I would not say that “efficiency” led to those losses…losses against a tough alliance that finished undefeated while fully functional.

That’s why Alliance 2 lined up 1337 against 40B in Tech. QF3-1.

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in this new game the key is going to be being able to reach into your opponents isolation zone. getting the 2 point bonus is going to be key, and thats why i think if you can score in the opponents 20" isolation goal as well as the three circular goals in the interaction zone, and the three circular goals in your isolation zone your going to have 7 goals with the +2 bonus, while they only have 2 goals with the +2 bonus. The key is also going to be getting the most out of the bonuses this year. Such as if you put a doubler on a goal that has 1 object on it your only going to get 4 points, while if you put a doubler on a 30" goal with 5 objects your going to get 12 points. The other key getting the most our of your negatiations, i think were going to see a lot of, both robots going to the interaction zone, one getting the doubler the other getting the negatiation and getting the most out of the bonus. I think we will each see what teams think of at our first regional competition. :slight_smile:

My early season advice to my team was to follow the highest scoring opponent; and at each goal they score on, remove all rings they put on (or have on); and then put on one ring of your own, if one of your rings isn’t already on it.

It should be easier (faster) to collect small numbers of rings, than to collect large numbers; and it should be easier to remove arbitrarily large groups of rings from a goal than it was to put them on it; and it should be easier to put one ring on a goal than to put several on.

At the end of a match there should have been a trail of goals we owned leading up a one or two goals they own.

If the opponent has a strategy similar to ours, then the match is decided by other factors (who executes it best, who had the best autonomous, who has the best ally).

Whether they fully embraced my advice is another story… I think it would have held up well throughout the season.


True… As evidence, you can look at how the 12 teams swept the mid-Atlantic area with this same strategy…

And yes… If only us students could learn to listen to our mentors… How much better the world would be…

(I’m in the unique position of being both a mentor and a student, so I can make all sorts of accusations and false statements… :P)

Huh, we (1107B, 7th seed) selected 40B because of 254A. On the other hand, we didn’t know that 1337 was a base in the ladder bot at the time.

Our primary strategy for the season was something we like to call the Pinch. What happens is both teams begin the game by moving to the corner with the 2 movable bases in it. They score on these two goals, and move outwards, towards the corner with the two wall goals. They score and descore on their way there, but the primary concern is to block any robots that try to get past them into their “territory.” Your territory is the area where your tubes are scored, and if anybody gets past, they will be free to descore all of your goals. Generally what happens is at around the 1 min mark, we’ve made our way up to the top corner, and their two robots are trapped in that area. They might try to escape, but we block them at the corners of the ladder- where the field is narrowest. This won us every game we used it correctly. Our 1 qual loss at worlds was due to a connection issue in our partner. In the end, I was actually improvising strategy, especially when I helped coach our A and C teams in Science division.

However, in the elimination matches, we knew that we would be facing 254A in the first semifinal, so we couldn’t use our strategy. They would drive under the ladder and start descoring our stuff anyways, so we had to change our plan. We chose 40B for their bucket bot hanger, and it was very close to winning us the match. Good game, you guys, it was more exciting than the finals.

For Gateway, I’ve pretty much divided the game into 3 main categories:

  1. Score 1st in as many goals as possible.
  2. Score more game objects than the other team.
  3. Use your doubler and negation barrel to full effect.
    Teams will probably be doing the 1st step for autonomous mode and maybe up to 30s in driver control, the 2nd step for until 30-20s left, and using the negation/doubler barrels for the last part of the game. Of course, the main question is how to best do each of these, and prevent the other team from doing the same. One last note is that the isolation zones have 3 goals each, but the entire interaction zone only has 3. I think that some games will be decided by who owns more of those 3 goals in the interaction zone.
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Maybe an alliance that can load up the isolation zone goals? While protecting them from negation barrels? While putting the doubling barrel into a really big one?

Here’s an idea: What can you do to get the opposing alliance’s doubling barrel? hmmmmmmmmmmmmmm…

well at the beginning of the year, you WILL have fail-bots that places the doubler barrel on the ground and fails to grab it

but by worlds, all the competitive robots will almost definitely have it loaded into their manipulator
the only way to stop them is to manually defend :confused:

Maybe a robot with an arm that will grab the doubler barrel?

Now THAT would be a good robot… One that goes around stealing barrels from other robots… hmmmmmmmmmmmm

I was trying to evaluate the relative merits of leaving room at the top for a doubler, but realized that it also left room and very good reason for the opponent to concentrate their efforts towards a negation piece. For all the time/effort spent in filling up a high goal (6+ game pieces), it seems reasonably prudent to simply level it off with a “normal” piece of your color. This would preclude doubling, but would more importantly prevent negating of a large amount of points (assuming your robot was able to dominate that specific goal).

In my opinion, a good strategy focuses on the idea of “securing” your points ensuring the prevention of point swings in the game that benefit your opponent. For example: the scoring of the green balls in the high goals in Clean Sweep and the low goals in the tower stratedgy for Round Up. It seems that fast paced Vex games with constant point swings caused by descoring and scoring require such strategy. The most important thing I believe that makes a good robot for any game is its ability to win in 1v2 matches (GER), especially at worlds. Your robot needs to be able to win matches without any help.

This years game seems much different and its obvious that scoring your alliances game piece first in each goal will definitely give you the upperhand. Getting that first game piece in each goal espcially one of your opponent’s goals (20 inch goal across the fence) would really turn the tide of the game.

A unique idea that I thought up for this years game would be to shove the doubler barrel in between the two 20 inch goals (the pegs) so that you double your points for both of those goals. As long as part of the game piece fits inside the goal, its considered scored. So its possible to score 8 points just on those two goals if you can be the first to score and get the doubler barrel on…

There is interaction between strategy, execution, and robot design.
It is not automatically clear to me why it is more important to prevent negating than allow for doubling; can you lay it out for me? Isn’t the point swing the same in either case?

If you find you are unable to execute a double faster than other team can do a negation, then filling to top would be wise. Counter strategy: if you can’t negate before they can double, then top their nearly full goal with your own piece to prevent either.

After the first spot in every goal is filled, evenly dividing your pieces between the other goals seems like a robust strategy to minimize the effects of doubler/negation.

Another similar d/n minimization strategy (or is it a tactic at this point), is to match opponent piece for piece in each goal. This also leads to higher quality points than the following D/N maximization strategy.

D/N maximization strategy is to double your own full goals, while negating their full goals. Its riskier, because they can aim to do the same to you.

For round up we witnessed that controlling the opposing alliances tubes was a contributing strategy.
This year their are 22 game pieces per alliance. So harvesting may be an option that comes up (although the game pieces are a lot larger than Round Up). From the isolation zone building a 4 bar robot could definitely enable you to score on 4 if not 5 goals. So during autonomous it might not be a bad idea at all to hit the opposing alliances isolation zone 20" goal first, to get the bonus before they do then continue onto your own isolation zone goals since its proves a much greater challenge for opposing alliances to score. What we also witnessed that early on at competitions such as Pan Pacific and even into worlds teams were moving game pieces to places the opposing alliance couldn’t touch them such as the ladder. What we may see this year are robots that gather up game all the game pieces from the interaction zone and feed them to the gated isolation zone. That way they can keep game pieces (9 from the interaction zone) from the opposing alliance to use as well as feed game pieces to a scoring robot that can hit 4 or 5 goals from the isolation zone. This strategy can lead to controlling 4 fully scored goals and half the opposing alliances pieces. I think the fastest, most efficient, intakes will have the upper hand in this competition.

2011 Design Award
2011 Future Award