Picking up fuel from the ground vs. using hoppers/retrieval zone

[AnnaCC]

Hi everyone,

Our team is having a discussion about whether to spend the time/resources/robot space on an intake system for picking balls up off the ground or if we should just rely on the hoppers and retrieval zone. We're building a simple high goal shooter, but gears and rope climbing are our priorities.

Although running across the field to get fuel isn't ideal, we'll probably doing it anyway for gears, and if alliance partners cooperate to collect fuel from hoppers simultaneously (keeping as much off the floor as possible) we figured it wouldn't waste much more time to run across the field than run around the launchpad chasing balls.

Of course, it's easier to defend against a robot that can't pick up balls from the floor, and any missed shots become irretrievable. But we're a little more concerned about being able to do everything else well, I think.

What is your team doing about fuel? Anyone have any other insights?

[carpedav000]

Originally Posted by AnnaCC

Hi everyone,

Our team is having a discussion about whether to spend the time/resources/robot space on an intake system for picking balls up off the ground or if we should just rely on the hoppers and retrieval zone. We're building a simple high goal shooter, but gears and rope climbing are our priorities.

Although running across the field to get fuel isn't ideal, we'll probably doing it anyway for gears, and if alliance partners cooperate to collect fuel from hoppers simultaneously (keeping as much off the floor as possible) we figured it wouldn't waste much more time to run across the field than run around the launchpad chasing balls.

Of course, it's easier to defend against a robot that can't pick up balls from the floor, and any missed shots become irretrievable. But we're a little more concerned about being able to do everything else well, I think.

What is your team doing about fuel? Anyone have any other insights?

IMO, floor intake is the way to go. If designed properly, it shouldn't take up too much space (see RI3D team Indiana's robot). Also, you'd be able to collect from the floor while on your way to get gears.

[bEdhEd]

If you're going to have a robot that loads from the top from the hoppers, then you might as well make a little bit of space available for a ball intake. What ideas have your team come up with for that so far? Are there images or videos you have already found from which you can draw inspiration?

We're going for a top loading and floor intake.

[Cothron Theiss]

I think a floor intake is absolutely essential for teams that want to be successful high goal shooters. However, you've already said that Gears and climbing are your priorities, NOT high goal shooting. If you are building mechanisms to retrieve and place Gears, a climbing mechanism, a high goal shooter, and a floor intake for Fuel, you will be effectively trying to build a robot that does everything. And as we see year after year, teams that try and do everything often fail to do any of the tasks well enough to set themselves apart. I think this'll be especially true this year. Another trend that I've seen quite a bit this year is teams that come to the conclusion that Gears are worth more points than Fuel, make Gears their top priority, and then invest much more of their time, robot space, and resources into shooting high goals. The point I'm trying to make is, if you've set out to make a Gear and climbing robot, make the best Gear and climbing robot you can. Don't divest resources from your primary scoring objective to add on a tertiary or quaternary capability.

Now, if you team feels strongly that you can add on a floor intake without detracting from the performance of your primary objectives, go for it! But this is an ever-present trap in FRC, and it catches many teams every year.

[AnnaCC]

Originally Posted by bEdhEd

If you're going to have a robot that loads from the top from the hoppers, then you might as well make a little bit of space available for a ball intake. What ideas have your team come up with for that so far? Are there images or videos you have already found from which you can draw inspiration?

We're going for a top loading and floor intake.

We've been keeping up with Ri3D, and our original plan was to have a belt/elevator style intake like some of those bots. I think the issue is less a lack of ideas and more that we haven't started prototyping an intake yet. We've lost a bit of mechanical expertise over the past couple years and worried that if we spread out too thin, we could end up with an entire fuel-scoring system that doesn't work well.

Originally Posted by Cothron Theiss

I think a floor intake is absolutely essential for teams that want to be successful high goal shooters. However, you've already said that Gears and climbing are your priorities, NOT high goal shooting. If you are building mechanisms to retrieve and place Gears, a climbing mechanism, a high goal shooter, and a floor intake for Fuel, you will be effectively trying to build a robot that does everything. And as we see year after year, teams that try and do everything often fail to do any of the tasks well enough to set themselves apart. I think this'll be especially true this year. Another trend that I've seen quite a bit this year is teams that come to the conclusion that Gears are worth more points than Fuel, make Gears their top priority, and then invest much more of their time, robot space, and resources into shooting high goals. The point I'm trying to make is, if you've set out to make a Gear and climbing robot, make the best Gear and climbing robot you can. Don't divest resources from your primary scoring objective to add on a tertiary or quaternary capability.

Now, if you team feels strongly that you can add on a floor intake without detracting from the performance of your primary objectives, go for it! But this is an ever-present trap in FRC, and it catches many teams every year.

^this. It seems likely that lots of teams will claim to prioritize gears/rope this year, decide that those mechanisms are fairly mechanically simple, focus on shooting, and then run into bugs later in the season that keep their "priorities" from working smoothly. Having to rely on hoppers or driving across the field for fuel during the match still makes me nervous, but hopefully our shooter will be able to just help us finish off the 40 kPa and score a few more match points when needed, and we won't have to rely on it as a main strategy.

[Lady-of-Fandoms]

My team has made it a priority to collect from the floor. We're planning on implementing a slash-and-burn strategy of dumping all the hoppers before anyone else could get to them, thereby starving opposing teams of balls.

[euhlmann]

Originally Posted by Lady-of-Fandoms

My team has made it a priority to collect from the floor. We're planning on implementing a slash-and-burn strategy of dumping all the hoppers before anyone else could get to them, thereby starving opposing teams of balls.

Opposing teams who didn't design a floor pickup*
I assume even the most basic strategy discussion can come to the conclusion that hoppers can't be relied on

[pmattin5459]

Originally Posted by euhlmann

Opposing teams who didn't design a floor pickup*
I assume even the most basic strategy discussion can come to the conclusion that hoppers can't be relied on

Yep. If our robot encounters any other shooters, we will dump every single hopper. It's a basic bit of defense that slows down many shooters' first pickup from a few seconds to however long it takes their floor pickup to fill their hopper (maybe around 5-10 sec?).

[g_sawchuk]

Originally Posted by pmattin5459

Yep. If our robot encounters any other shooters, we will dump every single hopper. It's a basic bit of defense that slows down many shooters' first pickup from a few seconds to however long it takes their floor pickup to fill their hopper (maybe around 5-10 sec?).

Sure, at a glance that's a fantastic strategy. However, let's look at some potential results.

If you do have a floor intake, I'll capitalize on the time you spend dumping the hoppers to squeeze in an extra gear cycle. That has the potential to make a big difference. Then, if you start scoring I will start cycling fuel in my retrieval zone, since you are feeding locations that I can load from. While you have the scoring lead, I have the gear lead (from when you were dumping hoppers).

Now, if you don't have a floor intake I'll start on gears, and just do gears continuously. I keep my one gear lead and you capitalize off of very little.

Not saying that hopper dumping (or better put, field reset's nightmare) is a bad strategy, just saying that it can be used against you.

[Siri]

I think folks are drastically overestimating how long it will take to finish a serious hopper race. In any worthwhile race, the only hopper that's "up for grabs" is centerfield (boiler side)--within a few feet and a few seconds of being on the path to a gear cycle. All the other hoppers shouldn't be a fight if the loader and defender are worth the effort--one each at least ought to be done by the end of auto. In fact the defender could decide to hit the centerfield in auto, perhaps leaving their own launchpad hoppers for their allies to hit on their way out (for a gear or what have you). The second offensive hopper should be hit by a loader's ally (upon good advice) no later than the start of teleop on their way to gear running and potentially doubling as the loader's blocker to the centerfield hopper. If the centerfield hopper is indeed still full by teleop, both parties are left to decide whether and how to race for it. But if you really can finish a significant portion of an entire gear cycle while the defender hits that button (which you have to pass approximately as well), it's probably an easy decision and you have bigger things to worry about. Like Einstein.

Separately, note that in a situation where a hopper dump tactic is worthwhile, relying on a single-gear lead countertactic necessitates both the ability to predict alliances' final gear totals and the luck that they'll end up on a rotor split. If that one gear does just barely let you finish another rotor, more power to you--but if you're so close to the edge, that usually settles the debate as to what you should be doing that match. It's also highly unlikely that the other alliance will end up one full gear cycle behind you in that case. To do so would be a mistake on their part that signifies they're really not on your level anyway--either they blew their time cushion or they should have stopped much earlier upon realizing they'll be a gear short. (The alternative case is your own alliance wondering why you ran a random extra gear that doesn't turn a rotor.)

From a strategic design perspective, a non-floor loader who poses a threat (i.e. made this as a competent strategic decision and properly executes) is more likely a fast gear runner who does fuel opportunistically from the retrieval station while grabbing a gear. They ought to be very good at the centerfield hopper race, though it's not a bad strategy try to beat them on your way past. Other than that and an autonomus load, they won't be preoccupied with hoppers in competitive matches (mostly because they really won't take long). Strategically that design decision screams high-cycle gear runner with some extra space/weight and design time. (If they're underperforming, of course, as with all defense the defender needs to reconsider pre-match whether it's worth bothering.)

[g_sawchuk]

Originally Posted by Siri

Separately, note that in a situation where a hopper dump tactic is worthwhile, relying on a single-gear lead countertactic necessitates both the ability to predict alliances' final gear totals and the luck that they'll end up on a rotor split. If that one gear does just barely let you finish another rotor, more power to you--but if you're so close to the edge, that usually settles the debate as to what you should be doing that match. It's also highly unlikely that the other alliance will end up one full gear cycle behind you in that case. To do so would be a mistake on their part that signifies they're really not on your level anyway--either they blew their time cushion or they should have stopped much earlier upon realizing they'll be a gear short. (The alternative case is your own alliance wondering why you ran a random extra gear that doesn't turn a rotor.)

I openly welcome you to risk 140 points during eliminations for the single gear that you don't complete because you wanted to dump the hoppers (or 50 for a hang that you might have not had time for as you raced to complete your 4th rotor).
I'm not quite sure as to why you think getting this one gear lead hurts you - you're working towards scoring while they're trying to counter you on a task you aren't targeting that match.
Please note that I never said if a floor intake or hopper intake was better - I think the others on this thread made that abundantly clear. Just providing insight with regard to countering hopper intakes.

We can apply plenty of levels of play to my suggestion - my thoughts are targeted towards a near-average level match up (perhaps slightly above).

[Chris is me]

Focus on your priorities. If a floor pickup takes time or resources or space away from gears and climbing, ditch it. If it doesn't, go ahead, that will have nonzero value. That's pretty much what it comes down to.

You'll be able to have some sort of ball game with human loading only. I don't think it's absolutely mandatory to floor pickup in this game.

[Siri]

Originally Posted by g_sawchuk

I openly welcome you to risk 140 points during eliminations for the single gear that you don't complete because you wanted to dump the hoppers (or 50 for a hang that you might have not had time for as you raced to complete your 4th rotor).
I'm not quite sure as to why you think getting this one gear lead hurts you - you're working towards scoring while they're trying to counter you on a task you aren't targeting that match.
Please note that I never said if a floor intake or hopper intake was better - I think the others on this thread made that abundantly clear. Just providing insight with regard to countering hopper intakes.

We can apply plenty of levels of play to my suggestion - my thoughts are targeted towards a near-average level match up (perhaps slightly above).

I expect that we mostly* agree with each other. My point was simply that people seem to be picturing one robot zooming around the edge of the field and hitting all the hoppers. A real race can't take nearly that long in reality, regardless of competition level. One robot getting to several dispersed hoppers in series at the start of teleop means by definition that either the other teams don't care enough to reach their nearby hoppers or they're broken/impaired robotically. Either way, even a defender that makes a habit of hitting every hopper they pass will reassess what they can do with their time. The point being that in matches where hopper dumping matters, the time trade-off will look much less like someone going far out of their way and more like situational defense in which someone hits me (or a hopper) while we're both working. Whether or not I choose to make that hit has a lot more to do with the specific field traffic at the time than any grand defensive or offensive philosophy.

The value of getting ahead of the opposition in gear cycling is a lot like other years, being chiefly determined by (A) your rotor predictions and (B) your time opportunity cost. Take a common competitive match situation in which we expect to be evenly matched with the opposition on rotors and climbing but may lag on shooting--it doesn't matter if it's Einstein or a regional qual. We can weigh this likelihood pre-match (with the final decision often based on autonomous scores); it's even arguably easier than in previous years given the massive time difference between finished rotors. So going a few seconds out of my way at the start of teleop in order to rapidly fill my hopper or prevent someone else from doing so may be a risk I decide is worth it. Perhaps I'll be wrong and have needed that time for a final gear that finishes a rotor. (This is why I said if you're close to your time cushion on finishing a rotor, the decision to gear is much clearer.) On the other hand, perhaps I decide not to hit the hopper, I still finish my last gear as expected, but then I can't get the last X balls that I need to beat their fuel score before the climbs. Or maybe I do win--or lose--comfortably, but I come up just a little under a 40kPa RP I really needed. In either latter case, hitting the hopper is a risk I should've taken and could've foreseen two minutes ago.

This is essentially like situational defense every year: sticking purely to offensive scoring at first--not detouring to hit a robot or a hopper--can feel like the conservative strategy, until it's late in the match and you realize you really needed to have made hit X while you were scoring in location Y thirty seconds ago in order to get/keep your winning margin. These situations go on and on every year, and they're among the most difficult jobs coaches have. The crux is that 2 seconds at time/location N do not have the same value as 2 seconds at time/location M.


*I will disagree on one point that, if one robot is in a position to want to go anywhere and dump (plural) hoppers in teleop of a what would be a competitive 4-rotor elim match, numerous people have already done something spectacularly wrong. A match like that (top-tier competitive and caring about hoppers) should have at maximum of one hopper any real distance away by the start of teleop, and that distance should be at maximum a few robot lengths off-course from someone who wants it. I may well decide to hit it if, as above, I expect to both need the 140 points and need that kind of fuel score. At an Einstein level nail-biter like that, trust me, you're not aiming for second place. It's very much go big or go home.

[snoman]

Originally Posted by AnnaCC

Hi everyone,

Our team is having a discussion about whether to spend the time/resources/robot space on an intake system for picking balls up off the ground or if we should just rely on the hoppers and retrieval zone. We're building a simple high goal shooter, but gears and rope climbing are our priorities.

Although running across the field to get fuel isn't ideal, we'll probably doing it anyway for gears, and if alliance partners cooperate to collect fuel from hoppers simultaneously (keeping as much off the floor as possible) we figured it wouldn't waste much more time to run across the field than run around the launchpad chasing balls.

Of course, it's easier to defend against a robot that can't pick up balls from the floor, and any missed shots become irretrievable. But we're a little more concerned about being able to do everything else well, I think.

What is your team doing about fuel? Anyone have any other insights?

If our teams meet a team like you are suggesting ( hopper feeder ) our teams will spill all the hoppers first thing..

[pntbll1313]

Originally Posted by AnnaCC

Although running across the field to get fuel isn't ideal, we'll probably doing it anyway for gears, and if alliance partners cooperate to collect fuel from hoppers simultaneously (keeping as much off the floor as possible) we figured it wouldn't waste much more time to run across the field than run around the launchpad chasing balls.

I recommend you think about your strategy for each stage of the competition. If you don't attend highly competitive regionals you should assume qualification matches will not have much FUEL being scored in the BOILER. That means there will not be much FUEL available after the start of teleop for you to use. If you face a strategic team they will dump all hoppers in the first 15 seconds of the match and make you try to outscore them at their game (I know teams in my area are already going to do this). In other words your great shooter may have about 1 hopper of benefit.

A very good High Efficiency GOAL scoring robot will be hard to build. If you are devoting that much into a great high goal scoring robot I would not want to only be fed by a HOPPER. Even at the Championship level I think winning alliances may have 2 GEAR focused robots. That means you would need to be the only shooter and after the first 20-30 seconds all you can contribute are the FUEL that has already been made and cycled back by the opposing alliance. So if you shoot 100% of their made shots you kept up.

Again this all depends on your team's goals. Think about what those goals are and the best robot to get you there