Where is the sweet spot?
 

This was one of the biggest debates our team had for the design phase: what level stack is going to provide maximum scores most consistently? Not in theory, but in practice, where tall towers tumble, and take time to make that could have been spent better.

Obviously the best teams will do six with RC consistently. But is it really wise for everyone to keep trying to stack six?

Anyway, we eventually settled on three. I'm curious as to what everyone else thinks. I'd do a poll, but I don't know how.

Re: Where is the sweet spot?
 

Using some linear programming and matrix math it's pretty easy to set up an objective function to calculate what height of stacks you should make using you handling times as constraints.

Re: Where is the sweet spot?
 

I'd love to see that, and your results.

Re: Where is the sweet spot?
 

Its the number of RC's your alliance has and max stack size taking into account that number plus the time it takes to insert a noodle. Minus the time to add to co-op stack plus any time left over to score totes and that will vary every match based on your alliance partners and noodle throwing.

Re: Where is the sweet spot?
 

...

Re: Where is the sweet spot?
 

I think it's just 6. It really depends on where you're aiming IMO.
At the highest level, it has to be 6 due to the cans. The cans determine the game at the high levels in regionals and on Einstein.
If you want to win a local regional, it's probably okay to go for less than 6 IMO. It might also be fine to go for fewer if you have valuable features like can grabbing or can capping.

Re: Where is the sweet spot?
 

I'd expect that, at the regional level, a quality alliance will be able to do a four to six four stacks, and if they control most of the bins then that will be sufficient. At Champs, stacking 5 with a bin in the playoffs will be a minimum.

Re: Where is the sweet spot?
 

Can someone do a poll? I can't figure it out.

Re: Where is the sweet spot?
 

Seems to me it's pretty dependent upon your robot design. (or maybe, your robot design is dependent upon what you chose as your own "sweet spot").

Our robot can do 4 but is happier with 3. But it can cap 5 if someone else makes the stack.

Re: Where is the sweet spot?
 

To clarify: I am concerned (or rather, interested) that we are overestimating how stable sixes are, and how quickly we make them. It's a classic gambler's fallacy: I've already put X dollars into this slot machine, so I'll stay here until it pays off. Drivers will underestimate the amount of extra time they are taking gingerly placing their carefully built full stack on the platform, and will waste time that could have been better spent making a second (shorter) stack for the same point value.

It also depends on your partners in any given match. If you are partnered with a team that can stack fast, but are slow to put the stack on the platform it might pay for that quick stacker to make the stack and pass it off to another team to be placed on a platform and start making another stack. The matches are going to be interesting to say the least.
Looking forward to watching the teams this weekend in Waterbury.

Re: Where is the sweet spot?
 

It is only a waste of time if that stack is not capped with a recycle bin. If the stack is capped, it is more advantageous to have a taller stack.

Re: Where is the sweet spot?
 

I've been running strat over and over in my head because it is kind of my job...

IMO if you are on an alliance that can reliably stack recycling cans on top of stacks, and you have robots that are capable of making 6 tall stacks comfortably, then it is definitely worth it to make 6 tall stacks because you have a bot that can stack them with a RC.

Otherwise, if you have to stack the RC yourself or do not have an alliance member that can cap the stacks off, it is much quicker to make stacks of three to four and make a lot of them.

It's kind of like R-strategists and K-strategists. Do you want to make a lot of little tiny ones or do you want to make little, but big ones? It depends on the resources you have.

Re: Where is the sweet spot?
 

From what I am gathering here it seems to be the general consensus is that the best way to score is the biggest stack you can make with a recycling bin as a cycle. Make a giant stack with a recycling bin, wash, rinse, repeat.
From practice videos that is all I see.
Is anyone willing to openly admit that they plan on deviating from that?

Re: Where is the sweet spot?
 

In addition to how tall your robot can reach, it depends on how long it takes you to line up to stack, and how precise your stacks are (do they nest, or sit on top, ready to fall in if jostled). Fast, precise stackers can go six. If you're either fast or precise but not both, probably four or five. If neither, probably two or three. If you can't make nested stacks, you may want to consider stacks that completely change direction so they don't "settle" later on.

We're hoping to get enough speed and precision to score four totes, then top that with two more totes and and RC, at least for the first stack or two. Later, as the cost of a lost stack goes up, we may go down to four. Until/unless you run out of space on the scoring platforms, there's no need to make uncapped stacks tall; they're 2 points per tote at any altitude (below the top of the backstop).

Re: Where is the sweet spot?
 

Moving a stack without it falling over, and placing it without falling over, become more difficult for most robots as the stack gets taller. The normal way to prevent it falling over is to move more slowly.

Some teams figured out good ways to move and place a tall stack quickly. They'll do well.

Re: Where is the sweet spot?
 

I am willing to bet all my rep points ("just dots", of course) that most teams are way overestimating the value of the tallest stack in terms of their actual capability. That includes most of CD, from what I've read for the past four weeks or so. I think the winners of many regionals will include robots that stack for three or four with RC. And that many robots that can stack higher will start to stack lower on purpose.

Maybe I'm wrong, but I am very interested on how this plays out. I just think that I see too much optimism out there currently.

Re: Where is the sweet spot?
 

The answer comes back as 5. over time.

Re: Where is the sweet spot?
 

It's not "too much" optimism; it's the right amount.

I agree with you that most teams still hope to do better than they will actually achieve. My team just happens to be one of the very few exceptions;). This is closely tied in with what the FIRST Robotics Competition is all about. In a competitive venue, safe designs constitute "playing not to lose"; bold, innovative, (and therefore risky) designs are "playing to win". If you don't push your limits, you're really just imposing your own limits.

Re: Where is the sweet spot?
 

Playing to win means a correct and solid analysis of the game. I admired teams that built 30 point climbers in 2013, but they were not "winners" in the sense that they didn't win the game (and teams like 118 abandoned their climber, even though it worked). My favorite robot of 2008 was 1583's little RC car, because they correctly understood that the field would be clogged, and a simple design that drove around in circles could win points. Deciding that building a robot based on the simplest math of the game is the way to win is usually foolish.

Re: Where is the sweet spot?
 

I agree with this. While there are exceptions, I very highly doubt the teams on Einstein are going to be making 3-tote stacks. If you can't make it to Einstein, then the point is moot anyway and you can go on making 3-tote stacks.
It comes down to how much you want a working robot with no risks versus a probably working robot that has potentially higher scores.
You do have to be consistent though.

Re: Where is the sweet spot?
 

Did you think the Einstein finals in 2013 would have 30 point climbing?

Re: Where is the sweet spot?
 

That's like rebutting a statement that the coach must train football players so they are fast and strong and skilled with a statement about the importance of game strategy and clock control. They're complementary, not exclusive.

If everyone on team 3946 decided that we would never be able to stack more than six game pieces in a match, we would have stopped programming last week and had limited driver practice and certainly be right. If we strive for 30, we'll keep getting better right up to (and into) competition. If we actually average 15 per match as a result, was that "too much" optimism?

Re: Where is the sweet spot?
 

I am certainly a fan of teams making their own goals for each year's game. If a team decides that their goal is to build a robot that is exceptionally beautiful, or elegant, or that achieves the most difficult task in the game, or that pushes the team's capability in programming, or manufacturing, or whatever, that is fine. But those are all different goals from building a robot that wins.

Re: Where is the sweet spot?
 

Apples and axe murderers. In 2013 you could score points by climbing and by throwing frisbees. This year, everybody stacks, so it's a matter of stability.
The vast majority of 30-point climbs were slow; the only really fast one I saw was 254 (of course there are probably others that I didn't see). It's the speed that matters, and even teams like 118 had a pretty slow 30-pointer. I didn't see a robot scoring 30 points in 7 seconds to compete with 254. Their elimination basically meant the end of a good 30-pointer on Einstein.

This year you can see tons of teams making 6-stacks really fast. 118, Shockwave, 148, and most likely other top teams as well like 254 and 1678.
5-tote stack maybe. But almost certainly 6-tote stacks. Thet're just worth so many more points when topped with a RC- which is what limits the big teams in this game.
There are only 7 RCs max for each team. In an even match, there are 5. Look at Shockwave's reveal video. A 6-stack in around 30 seconds. Multiply by 3 robots and assume that they are not outshining everybody by a lot.
5 RCs means 6-tote stacks. After the RCs are used up do what you will.

EDIT: I don't think I'll reply to this thread again. I see your point, you see mine, not a lot of reason to just rehash. :)

Re: Where is the sweet spot?
 

I expected some, but am not greatly surprised. In 2013, if the alliances at the top level had generally been able to score all 60-odd discs they had available to them in 150 seconds in their highest-scoring goals (also leaving few/none for the other alliance to sweep up), being able to climbing high as well would have been critical.

This year is a bit swapped around from 2013. I expect top teams, and quite a few medium-level teams, to get a tote stack or 3 RCs (or both) to the auto zone. Once you have a tote stack, you only need to spend a few more seconds on coopertition, provided that the center aisle to the step is clear. The RC is the highest-value game piece, and apart from the yellow totes, the scarcest. Further, its point value is directly proportional to its altitude. This means that getting RCs and scoring them high will be the most important things in teleop. Best scoring of noodles is next, finally followed by scoring any remaining totes (including the ones on the step). Uncapped totes do not need to be in such tall stacks, though you have to be careful not to run out of room on the scoring platforms before you run out of totes. As processing litter is only 1 point per piece for so few pieces, and usually requires a different mechanism, I would be surprised if many robots, including on Einstein, had noodle manipulators at all. I expect even fewer with noodle manipulators that aren't either serendipitous or about as complex as a plow blade.

Re: Where is the sweet spot?
 

I wish I'd said that!

Re: Where is the sweet spot?
 

And I wish neither of you had, since what I have wanted to know from the get-go is, where do you think the average team should be aiming to maximize their own scoring, not what will win Einstein. But I guess I can safely put you both down for "six".

Re: Where is the sweet spot?
 

My thought is that if your goal is to do well at a regional stacks of 4 would work well if you are fast in transporting them to the scoring area, and maybe stacks of 5 if you are slower. Both of these assume you have a robot on your alliance that can cap some of them.

Re: Where is the sweet spot?
 

Did you put a stopwatch on how long it took to build those 6 stacks? Those videos put the robots in best light.

Re: Where is the sweet spot?
 

If you're figuring just what your team can accomplish in 2:15 minutes, you can break it down to points vs time.

For every tote you have 2pts
For every tote with a bin on top you get 6pts (This works across the board. If you get 6 bins, you could stack 6 single level totes with a bin on top for 36pts. Or a 6 level tote stack with bin for 36pts)

Now a sample equation can be:
135s = T +

Never mind I just put it into a spreadsheet to make it easier. I gave everyone "edit" access, so play with it or make a copy.
https://docs.google.com/spreadsheets...it?usp=sharing

Re: Where is the sweet spot?
 

Emphasis mine:
As for aiming, yes, six, unless your design prohibits it. As for finding your actual sweet spot for execution, practice, practice, practice. Scout yourself while doing it. Find out what your sweet spot is, preferably on the practice field and not in the arena.

I anticipate the median sweet spot for execution at regional seeding to be 3, or perhaps 4; un-nested stacks get unstable quickly above 3.

Re: Where is the sweet spot?
 

In my opinion, teams that can do stacks of 6 will take their time to create those stacks, even in early weeks, because of the large points involved. While they are doing the larger stacks, the "support" teams will be making quicker stacks of 2 or 3 and getting them on the scoring platform and then coming back to add to them later.

Totes are worthless unless they are on the scoring platform, so IMO teams are better off making quick stacks and getting them on the platform asap, even if they are "stacks" of 1.

Re: Where is the sweet spot?
 

We thought that the sweet spot is 6, and I think the actual sweet spot will be apparent when we get into the competition. What I am concerned about for some teams is that they became convinced that 3 or 4 is the sweet spot, but if it really does turn out to be 6 then they are in trouble. We can do 6, or 5, or 4, or any number we want, so when the sweet spot becomes clear we will be able to do it. This is about building your robot to be able to perform whatever strategy is revealed to be the best, rather than trying to guess the best strategy from the beginning.

Re: Where is the sweet spot?
 

Remember that a stack is nearly worthless without a bin. Not that it won't give you points, but that pushing 4 totes on the platform in the last 10 sec is worth the same as a 4 tote stack that takes 30 sec.

Re: Where is the sweet spot?
 

Keep in mind that one stack of 6 with a RC and a noodle is worth less than two stacks of 3 with a RC and noodle. So if your robot is capable of making one 6 stack or two 3 stacks, the 3 stacks are worth more to you.

This will be different for everyone so I recommend during your practice you time how long it takes to do different variations of stacking to find your teams "sweet spot."

It could be anything like four stacks of 2, up to a stack of 6 and a stack of 5. But find your limits and play to them. Also don't forget the co-op! I predict it will make up over half of most teams average scores.

Re: Where is the sweet spot?
 

Good idea! I wonder if we can compile enough scouting data to execute this for the whole alliance, not just our team.
This covers the case where time is the most limited resource well. Another thing to consider is that quite a few alliances are going to run out of RCs, either because they have no grabber and are limited to the three in the staging area, or they're awesome and used all seven, or somewhere in between. When RCs are the limiting factor, it may be worth taking the extra seconds to make a capped stack taller as opposed to stacking more uncapped totes; as you noted, a capped tote is worth thee times as much as an uncapped one, assuming a single stack of upright or inverted totes.

Oooh - I wonder if making our top stacks sit on two bottom stacks rather than one would be more stable? (We plan to stack and score four totes, then cap with a stack of two more totes and a vertical RC, noodle optional.)

Sour spot
 

Don't ignore the possibility of a "sour spot" for some robots. Because of the vertical range and style of our lift, four is likely to be a sour spot for us. What I mean by this is that we may need more margin time to get from 2 to 3 and from 3 to 4 totes in a capped stack than to get from 4 to 5 and from 5 to 6.

Our uncapped stack timing should be closer to linear; the sweet spot will be risk-based.

Re: Where is the sweet spot?
 

Teams are often overly optimistic. Take a look at the poll results for how many people will be doing a 30pt climb in 2013: http://www.chiefdelphi.com/forums/sh...ght=climb+poll

46.6%? That didn't happen.