Low Bar

[Boltman]

Originally Posted by Joe G.

I'm pretty surprised, and just a little worried, by how many teams are responding "yes" to this poll. I say all this as part of a team that, after much deliberation, decided to go for it, but I'm worried that there are a lot of teams out there who are not fully thinking through the rather dramatic implications of designing for the low bar, and the actual strategic value of it to the average team.

I think that there are a lot of FRC game tasks, or even just general robot characteristics, which teams do not attempt or prioritize every year simply because somebody told them "trying to do everything is bad, simple is good" rather than out of a tangible, well thought out reason that it's going to be difficult for the team to pull off, or because of a valid trade-off which improves performance elsewhere. Shifters, for example. I have a hard time seeing how choosing one bulletproof, battle-proven COTs gearbox over another bulletproof, battle-proven COTs gearbox makes a robot appreciably simpler, or quicker to put together. Last year, the classic case was canburglers. The vast majority of FIRST teams dismissed this task as "too hard," only to have teams that didn't see it this way rapidly retrofit their robots to steal cans during lunch. This year, I expect to see teams fail to meet their potential in this way in regards to scaling. It's an easy task to dismiss, but also an easy thing to add after the fact (look at the WCP MCC, for example). The common thread is, it can be achieved through an "auxiliary" mechanism, something that can just be slapped on top of a robot without affecting the rest of it that much. And it's pretty close to a "binary" task; unlike something like shooting where there will be a huge spectrum of performance with gains to be made by optimization at every level, you either scale or you don't, and there isn't much to be gained by spending a huge amount of time optimizing how quickly you can do it. I would argue that some of the defenses also fall under the category of tasks more teams will avoid based on philosophy than sound engineering analysis.

The low bar is not one of these tasks. It is the opposite of these tasks.

The ability to do the low bar is immensely integral to a robot's design. It affects every single element of it, and disqualifies a number of otherwise viable designs and approaches.

The low bar takes practically every archetypical design from the previous game to which you could effectively say "build team XYZ's robot from that year," Rebound Rumble, and throws them out the window.

The low bar will make your electronics team cry.

The low bar has a direct and dramatic impact on the effectiveness of every single subsystem of your robot. Instead of releasing boulders from four feet up, you're either releasing them from one foot, or adding in systems you didn't need without the low bar to make up the difference. Same with hanging, your reach distance changed dramatically.

The low bar also has its advantages. It's one more defense that you're guaranteed to be able to breach, taking the number of other defenses to design for down from 8 to 6, and possibly eliminating some of the ones which require dedicated mechanisms to achieve. It's also the most direct path to/from the secret passage, probably the fastest defense to cross, and provides you with an optimal cycle time.

I'm worried, however, that a lot of teams are overestimating the degree to which they'll be able to take advantage of this.

By doing the low bar, you have made being an accurate high goal shooter quite a bit harder. You have also made your shots easier to defend if you stick to a low release point. Teams doing the low bar are betting on being able to make up the difference through an increased cycle rate. The number of extra shots a team can expect to miss by building for the low bar is hard to estimate, but likely not trivial, and I would argue that for many teams and the rate at which we've seen that defenses like the rock wall and rough terrain can be crossed, it may be more effective to cycle over these with a taller robot. They are also betting on consistently being effective enough to take priority over their alliance partners in use of the low bar. If as many teams want to use it as people say there will be, there's going to be a traffic jam through the thing.

By doing the low bar, many teams are completely neglecting the possibility of scaling. These teams are demanding an extra two high goal boulders a match from their low bar cross, minimum.

For teams that have chosen to neglect the high goal, the picture is even more stark. A team would need to run five extra cycles per match to make up the difference from a scale, a task which becomes dramatically easier if you allow your robot to be tall. I would bet that most teams won't even average five a match, let alone five extra cycles due purely to low bar efficiency gains.

Many teams are designing to be "breaching specialists," crossing all 9 defense styles. This gives them an extra five points per match (and no change in RP), when compared to crossing 8. Scaling, or even a single high goal shot, does the same or better.

And that's all neglecting alliance partners. The low bar is weird, in that it can be reasonably expected that both the best and worst teams in FRC will be able to do it. For the best teams, the advantage in cycle time is clear, and it's integral to their strategies. For the teams that struggle to put a kitbot on the field, taking away an effective way to score points that you're given from the start would be a poor idea. For a team in the middle, it's a reasonable assumption that their partners will be able to take care of it, and may be actively hogging it for their own cycles.

I also think Dr. Joe is right. But teams should consider, which will be the more effective robots? The ones which were designed for five weeks to do the low bar, and then hastily had a few tall bits added? Or the ones which were designed from the beginning to take full advantage of their height?

Unless you expect to be able to take full advantage of the low bar's efficiency gains, it may be in many team's best interests to walk away from the extreme design tradeoffs that the low bar forces.

Crossing defenses is not a problem with a good low bot and a HG shooter is definitely doable. The biggest "obstacles" are having to go further to touch the bar and scale (in endgame) also bumper placement. Everything else is doable. In fact its all doable and stay under 14.15" except during endgame.

It really boils down to can you design bumpers and a mechanism to scale. If teams are playing defense with a taller bot then you may be at a disadvantage however how many teams will play defense first off and secondly have a tall bot doing that sole task? I feel this will be a rare situation.

On the plus side limbo/low bot gives you pretty much automatic destruction of one defense or 25% of way to BREACH. Also it is likely lighter meaning less scaling (winching weight) issues.

I see a well designed low bot as a better choice than a well designed high bot for the sole reason it can cross a defense the High bot cannot ever in every match. All other things balance out. So well designed LB > well designed HB with all else being equal IMO

The only thing High Bot brings is defense possibility and possibly easier engineering solutions (crossing, goals and scaling) and bumper placement IMO and it seems other teams opinion according to the poll.

I think we will see more low/limbo bots than high bots this year from both less experienced and moderate to top end teams. Look at FRC champions lots of low bots through history they are prevalent.

[MrJohnston]

I agree with most of the assessments above... However, I do see being short enough to go under the low bar as being a very important aspect of this game.

* A robot hoping to advance out of District/Regionals has to be able to score points, even when allied with inept partners. There are two primary ways to do this: damaging defenses and scoring boulders.

* If a bot is designed to primarily damage defenses, being low is almost mandatory - Being short allows to you easily damage one of the defenses with no manipulators required (or even a fancy drive train).

* If a bot is designed primarily to score boulders, its design must consider from where it will acquire the boulders to score. The most reliable source will be its own secret passage - to which the most efficient path is under the low bar.

Though, being low isn't "mandatory" - its not like all three robots on an alliance will likely be able to share the path under the low bar to the secret passage particularly well, being low doesn't prevent other options (such as going through a different defense to attain boulders in the neutral zone; picking up missed shots in one of the courtyards or sneaking into the opponents secret passage to swipe a loose boulder)....

Yes, we have s short robot.

[staplemonx]

Originally Posted by Billfred

We already almost had this with Robot in 3 Days--late Monday night, the Team Cockamamie robot sprouted a new piece to lower the Cheval de Frise or raise the portcullis. All of a sudden, the low bar became verrrrrrry tricky to manage, usually with a little bumping. Teams had better beware.

We are design for 14" did you see any issues with anything below that height when crossing in either direction?

[Karthik]

The results of this poll are terrifying.

[Billfred]

Originally Posted by staplemonx

We are design for 14" did you see any issues with anything below that height when crossing in either direction?

We built for 15 7/8", and we were just scraping; 15 1/2" probably would've done it for that robot. Your mileage may vary based on wheel placement and angle of attack. (I drove the robot for the reveal video, and I had better luck coming in at a slight angle than straight on.)

[New Lightning]

When I see this pole I get the feeling that plenty of teams have come to the relatively same conclusion and that is that the consistency of the low bar out weighs many other considerations when it comes to design. What I believe is that most teams say that "we'll go under the low bar and then will just try to drive over some of the other obstacles and that will be enough for us."

What I don't think that many people have realized is that this will in fact not be enough in terms of a productive and winning robot. The robot will need to do something else. And making the decisions to go under the low bar limits your options in terms of other implements. A good robot, wanting to under the low bar, will need to be either able to shoot into the high goal or climb the tower in order to have any kind of value in eliminations.

[MrForbes]

Maybe. Or maybe the low bar robot will be able to get a lot of ranking points, by ensuring that the alliance will breach and capture, using the quickest and most reliable methods. Then they'll be the ones picking the alliance for eliminations.

It will be fun to watch what happens

[Billfred]

Originally Posted by Karthik

The results of this poll are terrifying.

Thought 1: It's a poll on ChiefDelphi, so it's a small sample of a small sample.
Thought 2: It's a poll on ChiefDelphi at the end of week 3, so it's a small sample of a small sample whose sample could shrink even further by ship date. (I know 2815 planned to cross the center divider in 2012...right until about Thursday afternoon at Peachtree when we determined there was a frame member about 3/16" too low that we missed when designing.)

Originally Posted by New Lightning

When I see this pole I get the feeling that plenty of teams have come to the relatively same conclusion and that is that the consistency of the low bar out weighs many other considerations when it comes to design. What I believe is that most teams say that "we'll go under the low bar and then will just try to drive over some of the other obstacles and that will be enough for us."

What I don't think that many people have realized is that this will in fact not be enough in terms of a productive and winning robot. The robot will need to do something else. And making the decisions to go under the low bar limits your options in terms of other implements. A good robot, wanting to under the low bar, will need to be either able to shoot into the high goal or climb the tower in order to have any kind of value in eliminations.

I think your list omits some ways teams can get into consideration at most events*, but I do agree on the core point: low bar alone doesn't hang your banner. What it takes to do so will depend on what the top teams at your event didn't do--because they'll need that in order to achieve the breach and capture points.

(Consider: A captured tower is worth at least 56 points in playoffs, before autonomous or high goals or scales. Really at least 66, since someone had to get balls across the defenses to do this. Viewed in isolation, a breach is 60 before autonomous. I figure you'll be able to win quite a few with a two-digit score from Week 0.5 until probably Week 2. After that, the phrase will be "breach and capture.")

*Championship? MSC? IRI? Those are not most events. Start scaling and hitting high goals.

[MrJohnston]

Originally Posted by MrForbes

Maybe. Or maybe the low bar robot will be able to get a lot of ranking points, by ensuring that the alliance will breach and capture, using the quickest and most reliable methods. Then they'll be the ones picking the alliance for eliminations.

It will be fun to watch what happens

I would think this... However, it sounds like a LOT of folks are building short robots designed to cycle under the low bar and score boulders in one of the goals.... If there are not very many robots that can effectively traverse some of the other defenses, one of those could find itself at the top of the rankings as it will always be in preliminary matches with robots that compliment (instead of duplicate) its abilities....

[Boltman]

Originally Posted by MrJohnston

I would think this... However, it sounds like a LOT of folks are building short robots designed to cycle under the low bar and score boulders in one of the goals.... If there are not very many robots that can effectively traverse some of the other defenses, one of those could find itself at the top of the rankings as it will always be in preliminary matches with robots that compliment (instead of duplicate) its abilities....

I think low bots fall into all categories and many who build them will be able to do all the defenses and still score goals and even scale . I is seemingly the easiest way to build a scoring kit bot for rookies, I'm pretty sure a majority of older team low bots will be very capable beyond the low bar given.

Remember all low bots can open the doors from behind too. So low gives you ability to destroy 1 and aid others on another defense every match.

In the end the poll results show an unwillingness to give up on a guaranteed scoring play and assisting on another at the bare minimum. High only helps in defense abilities due to height. But limbo bot may transform to high.

[mrnoble]

Originally Posted by Karthik

The results of this poll are terrifying.

Why?

[wireties]

Why are folks assuming a robot that can limbo cannot cross other defenses as well? I understand, a little, why a low-rider may have trouble opening doors, lowering bridges or raising the portcullis but why would a low-rider have trouble with the other defenses? The low bar is not so low that it impacts wheel size choices. drive train choices etc.

[MrForbes]

yup, we seem to be able to get over them with kit wheels on a slightly modified kit chassis.

[MrForbes]

Originally Posted by Joe G.

The low bar will make your electronics team cry.

Why? We have room for a nice size electronics board, mounted near the top of the robot...easy access, etc. It took our electronics team about an hour to mount the parts and do the preliminary wiring.

[Dezion]

Originally Posted by wireties

Why are folks assuming a robot that can limbo cannot cross other defenses as well? I understand, a little, why a low-rider may have trouble opening doors, lowering bridges or raising the portcullis but why would a low-rider have trouble with the other defenses? The low bar is not so low that it impacts wheel size choices. drive train choices etc.

Our robot can fit under the Low Bar and, in theory, should be able to cross every defense by itself, so it's not impossible. However, this trade off my cause severe issues if we try to scale the tower as we'll have to develop something to grab the rung, which may prevent us from going under the Low Bar after it's added, which is also why we're considering it to be removable.

If you do go under the Low Bar, it's going to make doing other objectives harder, but not impossible.