Longest Launch Distance for Spin Up

I wanted to calculate how far our flywheel needs to shoot in order to land a shot from the farthest reasonable shooting spot on the field. Here are my rough calculations:

The red square is the robot position, the light blue lines are the measurements. In theory, you need to shoot a disc high enough that when the disc reaches 13 feet, it is above 25 inches (the bottom of the high goal). I just thought that I would share this with everyone that is doing some early season testing on flywheels. Thoughts?


I don’t think it’s practical to shoot from that far away so you shouldn’t design around it

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Here is the shortest reasonable distance if anyone is interested

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I think there is a good chance teams will eventually need to figure out how to shoot discs in from the back of the goal, in order to fill the goal up completely. If you only shoot in from the front side, you are severely limiting the capacity of the goal. if someone figures out how to do that while nobody else can, that team will be able to fit far more discs in their goal than anyone else.


I think that shooting from different angles should be able to fill up the high goal fairly well, with discs naturally settling out when more discs land in the high goal, but I do like the idea of shooting from the back of the goal.

Why wouldn’t you shoot from inside your own low goal? Of course, you would be taking away points from yourself, but if you were behind you might have to.

You would definitely want to shoot from inside your opponent’s low goal, even if your high goal is full. Shoot backwards at your own low goal.

I totally agree that. I think the game will be like :

  1. Try to get match load until no more left
  2. Get to your low goal and try to shoot them to your high goal(much more accurate if you stay in a particular zone)
  3. last 15sec, roller
  4. last 5sec, expansion
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I think the game will be like

  1. In auton, try to get as many as possible into your high goal before the other teams can get to them.
  2. Spin the rollers for the AWP.
  3. In driver, keep running around getting as many discs in your goal as quickly as possible.
  4. In the remainder of time, shoot into the low goal, take discs out of opponents’ low goal, or encamp around rollers until endgame.
  5. Endgame expansion.
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You can create an arc with the 13 foot line, which covers the corner tile of the low goal, and I think people will probably only be shooting from that tile so that they don’t hit the opponents high goal with discs (unless it could be used to knock them out?!?!?)

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In NBN teams built for a 17ft throw (diagonal of the field perimeter). You can always dial the motors back if the distance is less and I also suspect that the goals have a reasonable amount of stopping power.


One other consideration is that robots cannot deploy their blockers (that little 2" x 6" extension) when in either low goal. So if the little blockers turn out to actually be useful (I know there are a lot of doubters, including myself) then the low goal is the safest place to shoot from.

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Don’t you have to shoot that far during auton though?

Couple of things:

a. I also had the concern initially that shooting from the front would limit the back of the goals capacity. However at the speed the frisbees are going to be going, the chain would likely just slow them down and a sizable and comparable portion of frisbees would land both in the front and back of the goal.

b. Rollers are a net 80 point swing, worth as much as one shooting 12-16 discs to compensate for losing rollers, so focusing on them at 20 seconds left can leave you in the dust and overwhelmed trying to turn the rollers and swing points. I envision that with high cycle rates and the importance of the roller in comparison to the already limited capacity of the goal, rollers will be the object of the match at 50 seconds to go. Fighting for the center of the field will be the name of the game at 20 seconds to go since that’s where you can most easily access most field tiles, or block most constructive expansion points-wise. At 10 seconds, you have to expand. Expanding late means that you will almost certainly run into more obstacles.

c. I think it will be critical to go for auton midline discs since having “control” or having already scored more discs means your opponent will be at a disadvantage. As to how much of a disadvantage; say you prioritized the 2 3-stacks on the midline, then you have 3/14 of the field discs in your “corner” at an advantage just after the auton. Thinking about it, you can score half of the field discs and your preloads just in auton, which means that your opponent won’t have as many discs in their “corner” or having already fired them into the high goal.

I think matches can be structured in these two ways, obviously more than this but this is what I think:

Auton: A team goes for as many discs as possible in the first 11 seconds and rushes back to get the rollers for AWP.

  • first 30-40 seconds is shooting discs into the high goal
  • next 10-20 seconds is blocking opponent shots into their already pretty full high goal
  • next 30 seconds is battling over the rollers, this is early so that teams get a head start in overwhelming their opponents so that they spend more time on rollers than fighting for an optimal spot for expansion, IF they don’t have a high cycle rate
  • last 20ish seconds is fighting for an optimal expansion spot. Since each tile is 3 points, dominating 20/28 tiles puts you at a 30 point advantage, enough to swing a match if you are down a roller and missed a couple of discs.

Auton: A team shoots all of their discs in the auton period, and retire their shooting mech. for the rest of the match.
Driver: The team then dominates the rollers and protects them until the last 15 seconds of the match, then gears up for expansion and gets the field tiles in one corner of the field.

The first match dynamic would be for a focus on being consistent and excellent all around, and the second match dynamic would be a partnered strategy focused on securing a quota of points no matter the opposing actions. In any case, rollers are far more important than scoring discs for a longer period.


I expect the goals will both be full at 45 seconds or so once we get to high level
matches. So for the rest of the match teams will have to make the decision to either score low discs, gain control of rollers, or keep hurling discs at the overflowing goal and hoping the discs stay in even when most of the time they fall out. I think at that stage gaining control of rollers will be key, but not in a swing way. I think the best move would
be to camp in the corner and maintain control of the two rollers close to that corner. You can’t contact both at the same time because of their spacing apart, but they’re close enough that you could probably maintain control of both, even under defense. And the corners might also be the best place to deploy expansion mechs, since you want to cover the most area without overlapping with your partner. So both bots being in the opposite corners might be the optimal expansion setup.


That’s what I’m thinking with scenario #2. But people with more robust drivebases can nudge others out of a corner, and if you get a head start on rollers it will be an overwhelming point swing since at that point the drive coach will probably be guesstimating points. You can also block corner expansions better with center field expansions.

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I think your reasoning is solid overal, but am confused by

Both alliances can cover the same tile, so by dominate 20/28 you mean what? Force opponents to not being able to expand and thus get only 4 tiles per bot? Seems unlikely.

The endgame points are going to make the matches strategic and exciting. That said, with the points not being zero-sum, getting a 30 point advantage sounds ambitious. I feel like a 9-12 point advantage is what will be at stake.


not necessarily, you can drive up to the center line

yes but the space behind the high goal is quite limited if the robot is going to be big.

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The problem with every robot trying to expand is that they will run into eachother. Sure, there will be overlap, and it’s not a zero sum game. But “dominating” field tiles rapidly and with force can quickly swing the endgame in an alliance’s favor. Additionally, not all robots will focus on expansion. You can picture a scenario where one alliance partner on blue is sitting on two tiles and can’t expand, or can only expand minimally and endeavors elsewhere. More than likely, another two robots are battling eachother and tangled up in last minute expansion efforts. Let’s say each of them gets 5-7 tiles. A strong expansion bot could then easily expand to touch 16-20 tiles, and with overlap the points total is similar to 20-8.

I think it’s important to note as I haven’t seen this mentioned anywhere - expansion will be a complex and multifaceted game dynamic as teams begin to develop counter-mechanisms and more consistent mechanisms. Expansions with more pushing force and greater speed will dominate the endgame, but not only this, mechanisms can be created such that teams block other teams from accessing tile points at all. Mechanisms can also be designed to get around obstructions created by other robots. Simply rolling out anti-slip mat simply won’t cut it against agressive and well-thought-out endgame action. This was a problem we saw in tipping point as well - how many times have we heard a commentator say that the only thing that an alliance one goal down could do to win was to score rings on the neutral branch? Instead we focused as a community on goal rushes, and built mechanisms that would shine for a second, and determine the whole outcome of a match, which was incredible but also left a lot of unexplored territory in rings.

I am going off on a tangent, but I’ll end by saying that as a community we should do more to diversify strategy, and the expansion this year is prime territory for that exploration.