Why go over the bump
 

In response to this thread, I see a lot of teams who say it's best to go over the bump, but not why it isn't, or why it's advantageous to go over the bridge.

So the topic here is: What are the advantages of the bridge vs. the bump? What are the advantages that the bump has that the bridge doesn't, and vice versa?

Re: Why go over the bump
 

I think that with the right setup, you can traverse the bump a lot faster than the bridge.

Re: Why go over the bump
 

Why handicap your robot?

Re: Why go over the bump
 

I personally think, contrary to majority belief, that being able to lower and use the bridge is a much higher priority because just being able to lower the bridge, can enable a team to gain a vast amount of points at the end of the round. Additionally, the bump may prove harmful to any unprotected electronics/mechanics underneath the robot. Plus, there is always the possibility that the robot my become stranded balanced on top of the bump (unless it is designed to not do so).
Hope this helps.

Re: Why go over the bump
 

We looked at the game and our strategies and thought "Honestly, how many times will we cross that middle section throughout the match". Our answer: 2, maybe 3 times maximum. We can use the extra time/weight elsewhere, most likely improving our bridge manipulator. Not only will we be better on the bridge, but we will be able to play our strategies much better than if we stuck to the bump.

Re: Why go over the bump
 

Your autonomous mode should do two things - make two 6-point baskets and go tip one or both of the allowed bridges to get the balls from it(them) onto your side. In fact, a good argument can be made for tipping the middle bridge your way should be your first priority, then return to the key edge (detecting that little bump) to make your free-throws. I see no advantage at all to kinect control. It is merely cape-waving FIRST-style. Perhaps I'll be surprised at Suffield Shakedown. I still can't guess how.

So dealing with the bridge is more important than crossing that barrier.

Re: Why go over the bump
 

We've found a few good ones, though I won't share them, think along the lines of this: You don't control how your robot does things, but maybe in a different way. Good luck! :D

Re: Why go over the bump
 

Honestly, I don't think building your robot to traverse the bump is worth the effort. How many times do you really need to cross it?

Re: Why go over the bump
 

The idea of going over the barrier appears to me as the choice of keeping the robot unpredictable to remain effective in the challenge. If a team is too limited, then other teams through scouting will notice and counter. Two bridges, one of them on the side requiring time to cross, seems quite limiting especially in the elimination matches with higher level play.

Re: Why go over the bump
 

Our robot's bridge device is the same device for climbing over the barrier, but climbing over the barrier will probably be our prefered method because it allows us to cross the field wherever and whenever we want to.

There are a variety of match scenerios that would show crossing the barrier is valuable. There are a variety of playing styles or strategies where crossing the barrier would be valuable... particularly on defense.

In our minds it wasn't an ability that required alot of time, energy or resources, esspecially when we combined it with our bridge tilting ability, so we wanted to have it. Time will tell how valuable it really is in a match... but my guess would be if more than 1/2 the robots on the field couldn't cross the barrier it could be really problematic and slow the pace of scoring and the match in general.

Re: Why go over the bump
 

It is nearly always advantageous to be able to go anywhere on the field quickly.

The bridges do not allow this by design. IMHO most of the "good" teams this year will be able cross the barrier with minimal effort on their part. However, these teams will also be able to manipulate the bridge in order to balance for the end game bonus. If you had to choose one, the bridge is the better choice as it allows you to attempt the end game without alliance assistance.

Re: Why go over the bump
 

I really can't think of an amazing reason that all good teams must be able to traverse the bump, but it does depend a whole lot on strategy. In 2010, the last game with zones separated by barriers, 254 and many other teams like it decided to only travel through the tunnel, and they played magnificently. (My team pretty much decided that going over the bump that year was pretty much imperative for success.) 469 didn't even plan on switching between zones at all!

Re: Why go over the bump
 

Agree with JABot67. In 2010, out team theorized that the tunnel would be too easily dependable to bother even designing the robot to go through. We were able (and fairly effective at) traversing the bump. As we all know, the tunnel did not get defended very much at all, and teams (like 254) used it with no problem.

This year, we have elected to go over the bump. Why? We again think (and probably incorrectly) that the bridge will be too easy to defend. Also, we want to be fast, and lining up with and crossing the bridge is not "fast."

Re: Why go over the bump
 

In 2010 we couldn't go over the bump (well...we could, but it was difficult for us. We did it once in an off-season event at Kettering Kickoff) which we thought might cause us trouble since it seemed that one tunnel would be easy to defend. It seems like we rarely were defended from the tunnel - even in eliminations on Newton field. This year, there will be two bridges to cross - one of which can't be defended without penalty...you can't touch the opposing alliances bridge or robot in contact with the bridge. That being said, I also agree that it's possible to design for crossing the barrier much quicker than the bridge. It's really up to the team to decide if the reward for being able to cross the barrier is worth the effort of design a robot that can do it.

Re: Why go over the bump
 

Because there may be designs which allow you to be more effective at one task by forgoing another task. Take 469 in 2010 as an example, how many times did they cross the bumps OR travel through the tunnel? It netted them 4 blue banners and a CMP finalist medal.

Strategies can sometimes call for other systems to be sacrificed.

Re: Why go over the bump
 

I agree, few will be crossing the field very often, but having the capability to do both the bump and bridge can be very important in the occasional situation

Pros: Can cross the field quickly, can play better defense, can get around defense more easily, faster crossing time, more appealing when choosing alliances

Cons: Heavier robot (if you use separate mechanisms for the bridge and bump), takes more time to develop and build, more expensive

Overall, it is good to be able to cross the bump, but it would probably be better to focus on other aspects of the robot such as shooting (unless you plan on doing hardcore defense, where it can be good to be able to quickly go over the bump)

Re: Why go over the bump
 

It's all about strategy. If you have a killer strategy that prohibits crossing the barrier then great, otherwise I'd suggest a more flexible solution.

Truthfully, it's all about your startegy, and your capabilities as a team.

Re: Why go over the bump
 

Why go over the bump is like asking why be able to score from different places on the field. Some teams are only going to be able to score from one place or only go over the bridge. If you and your partners can only go over the bridge or only score from the same place then the game is going to be very slow and low scoring for you.

Being able to traverse both the bridge and the bump, as well as being able to reliably score from at least 3 places on the field is going to make you a better partner to play with, as you will not be interfering with your partners as much.

Re: Why go over the bump
 

We saw the bridge as the main priority since it allowed a considerable bonus at the end of the match, and also allowed traversal into the other half of the field. So why cross the bump? In the case of traffic issues (and even just normally) it will likely save time, and the relatively simple mechanism we are using for the bridge will work identically for the bump, requiring only a more specific wheel configuration. So for us, the extra design complexity was minimal, so the minimal cost was worth the potential gain (though it may prove only marginal).

Re: Why go over the bump
 

The game would not be very slow and low scoring if there were three robots on the same alliance that could only score from one place (e.g. the key). You just need a good passing game, and reliable pick-up from the ground. With this strategy, robots would not have to cross the bridge very much.

Also I have my doubts on more than a handful of robots being able to accurately score long-distance. I may be wrong, but it's the way I see it and a whole new discussion could be made out of it.

Re: Why go over the bump
 

Personally, I don't really see such a conflict here. I do think going over the bump should be accounted for because, as said before, why handicap your robot? If I had to choose between the two, undoubtedly I would absolutely choose the bridge. As with the mini bot last year, getting those end-game points are worth like 3+ baskets, more if you have multiple robots on the bridge. The end-game as last year, I believe will be very important and a wise choice. Do you get any point explicitly for crossing the bump. No. I know I know, It saves valuable time, but really, will it equate to a 10 (or more) point bonus? Yes, you could have other teams tip it for you, but I really don't think we should design our robots around other robots. But, I said if I had to choose.

Thats the thing, you don't!

This isnt some majorly complex task to solve. It just takes some ingenuity, which is what FIRST is all about!

It seems extremely possible to me to design a drive base that can cross the bump and also a bot that can tip the bridge. There doesn't need to be some extravagant mechanism, just a lever of sorts to tip the thing on the front. And my team has a drive base that just drives over the bump! No extra moving parts!

I think that the bridge is more important, but in the long run, a team like mine will be able to do both and we don't have any extensive resources or huge grants(We are in the two thousands).

Just my two cents!

Re: Why go over the bump
 

Bridge vs. barrier isn't an either/or choice. If it was, then bridge. But it isn't so be capable of both. With a limited ball supply, one alliance can control them all. Perhaps the best way to get and maintain control of the ball supply is to feed primarily from your own rebounder lane, collect your opponents missed shots, and carry balls to the key rather than throwing them across the field. You might find yourself crossing midfield very often. Keep your options open.

Re: Why go over the bump
 

No, it's not possible for one alliance to control all of the balls, even if one alliance is really terrible. An alliance that plays the hoarding game can hold on to a large majority of the balls, but only by not scoring while allowing opponents to score and thus digging themselves a hole. An alliance whose opponents have pathetic accuracy can hold on to a large majority of the balls, but do you really want to plan your strategy around your opponents being inaccurate?

Re: Why go over the bump
 

When our team first thought it through, we thought that we needed to get over the bump, but we analyzed the game more. We figured that one team will defend/score, team2 will score, team3 will shoot balls to the other side from the team lane. So if this is the case you will need to cross the bridge/barrier at maximum 2-3 times a game, so even if it takes a few more seconds to get over the bridge, it's better than using a lot of time/effort/weight to make something to cross the barrier.

tl;dr we thought that going over the bridge is better

Re: Why go over the bump
 

This actually wasn't a problem for us, because our bridge mechanism allows us to get over the bridge without stopping, and may actually be faster than going over the barrier.

Re: Why go over the bump
 

Of course it is. An almost arbitrary number of balls can be placed in the corner of your alley, which a diagonally-parked robot can protect just by sitting there.

Don't be so quick to dismiss strategy... Besides awesome versatile robots, it's what wins games every single year.

We were lucky enough to off-season prototype a drive train that is just about perfect for this particular game; it's heavy and rather expensive (though not really, due to the awesome donation from Gates), but as far as time/effort it was a clever use of band saws and day and a half of tweaking/re-tweaking to traverse the barrier... and as for weight, we're at 107 lbs including everything but a few wires.

It's likely too late for many teams, but I think that teams that can't cross the barrier will be bitten by it at some point this year. In 2010 we were first seed tournament champions at FLR without ever once even trying to cross the barrier (we could, sometimes, inconsistently...) There were several games at Championship where we could have won had we the ability, but we didn't, so we didn't.

tl;dr version: If studying the elite teams has taught me anything in the past seven years, it's that the drive train is absolutely the most important aspect of your robot, hands-down, no contest.

Re: Why go over the bump
 

By my interpretation of the rules you can't have more than 3 balls there since trapping them in that manner is considered controlling them.

To answer the question of the post. Why go over the bump? It's faster and I believe safer too since there is less chance of tipping over. We plan to only go on the bridge to balance.

http://tahomarobotics.org/2012/02/02...bump-part-two/

Re: Why go over the bump
 

I can definitely understand why someone thinking designing only for the bridge and not for the barrier would be totally okay. It's something else to design for, and realistically, will probably only add a few second (if that many) to your trips across field, which, unless you're making frequent trips, isn't really that bad. However, I see only crossing the bridge as a "Well, what if..." situation. There are things that, if you can only cross the bridge, could hurt you.

Well, what if...

• Both of your alliance partners can only cross the bridge: If your match strategy dictates all of your alliance partners (or even just two of you) to be crossing the bridge, it's going to get crowded at times. And unless two of you have a REALLY thin robot you feel comfortable running side by side on the bridge, it's going to cost you valueable seconds of gameplay.
• One of your partners takes a spill on the bridge: Say one of your partners it crossing the bridge and they tip and fall. Not off the bridge, but they fall and block the bridge on one side. Then, not only can you maybe not balance in the end game, but you can't traverse the field via alliance bridge. You can still use the coopertition bridge and the opponent's bridge, but you're not protected by your bridge and alley, and you risk penalty by using the opponent's bridge, especially if you happen to be crossing close to end game time.
• Something malfunctions: Most team's bridge manipulators (from what I've seen, and admittedly partially through assumption) will probably be some kind of arm that swings down and pushes the bridge into position to drive on. And nothing ever breaks :rolleyes: If a part of your robot snaps, comes unplugged, or just gets stuck, you suddenly are without a bridge manipulator. While I've yet to see/come up with a passive bridge manipulator, there is at least one way to traverse the bump passively (i.e. with the right kind of wheels, you can just cross the barrier).
• You ARE making frequent trips: Teams like 1114, 254, 217, etc. will probably be looking to make frequent trips across the field if they don't have a good feeder bringing balls to their side. Say they are sinking all 3 shots (entirely possible), not leaving any rebounds to get. If they want to make 5-10 trips a match (just throwing out numbers), say crossing the bridge takes 3 seconds and the barrier only takes 2 seconds a match. Overall, the bridge takes 15 - 30 seconds, while the barrier only takes 10 - 20. As the match progresses, the bump with allow more time for scoring. These are, of course, hypothetical numbers. In practice, we'll actually see how things turn out. Conversely, if these elite powerhouse teams can only cross the bridge, maybe you don't want to use the bridge, for risk of getting in their way? Just a thought.

These are all very real possibilities and, though you may not see them happening every match, even just happening once can cost you. Being able to cross the barrier may not be a necessity, but having the added versatility will almost definitely come in handy several times at a competition.

One the other side, however, designing for the bridge ONLY does have it's advantages.

• Less to design: If you're a team with limited resources, you're almost definitely going to want to design a simple robot at possible. Adding design for the barrier can take valuable time and resources, as well as adding wait and, depending on the method, complexity.
• Focus on one thing: If you take the attention that could be divided between bridge and barrier, and focus only on one of them, then you should have a bridge or barrier manipulator that is doubly effective. With the major impact of the end game this year (either by being able to use the co-op bridge, or getting the points for your own bridge), having an effective bridge manipulator can make an alliance successful, as well as making you highly desirable in alliance selections.

So only being able to use the bridge may not kill you. Just having the added versatility can help you out a lot.


I hope this helps!
-Leeand

Re: Why go over the bump
 

If done right you should be able to make your robot drive right over the bar without much robot work. (Track drive works great) then have plenty of weight to add other things like:

Ball shooter

Bridge handler: I say this because you might want to be able to raise, lower or help balance the bridge

Something to play a little defense



I think there will be a lot of robots that will be able to do all this and more. So do not limit yourself too do just one or the other.

Re: Why go over the bump
 

R22 reads "Moving or positioning a Basketball to gain advantage is considered actively controlling. Examples are “carrying” (holding Basketballs in the Robot), “herding” (intentionally pushing or impelling Basketballs to a desired location or direction) and “trapping” (pressing one or more Basketballs against a Court element in an attempt to shield them)."

Parking a robot in the corner of the court with basketballs between the court boundaries and your robot is neither carrying, herding, nor trapping. No touchy, no trappy.

Re: Why go over the bump
 

Better double check, I think I saw a GDC response that make your proposed strategy illegal. In my view, it is less-than-stellar sportsmanship at a minimum. This a game for engineers, not lawyers! ;o)

Re: Why go over the bump
 

A. The Q&A is very easy to search by rule. Of the nine questions asked and answered related to G22, one indicates that I'm right (without explicitly saying so, but given that FRC is a restrictive rules set and not a permissive one, they don't have to say so outright) and the rest don't address it.

B. Your opinion on the sportsmanship involved is irrelevant to a discussion of strategy. It would be a mistake to dismiss what could be a valid strategy as "rules lawyering". Even if you have no intention of doing it, you should be prepared in the event that your opponents do.

Re: Why go over the bump
 

I agree with your interprentation and in no way view it as unsportsmanlike. There has been nothing wrong with slowing the game down and hoarding game pieces in past games (other than 2008 when you couldn't control your opponents trackball).

According to the Q&A, one issue with that strategy is that if you touch the opponents robot in your ally, you get a red card due to G45. Its a ruling I completely disagree with, but it is what it is...

Re: Why go over the bump
 

While our bridge mechanism is not passive, once we "deploy" it, it is then passive

Re: Why go over the bump
 

I assume you're referring to the 3rd point under why to design for the bump.

This is true, but it does have to be deployed. And whether by motor or pneumatics (or some other system), there will be some chance for the system to fail. Like last year, with the minibots. If a team had a pneumatically powered deployment system, and a pneumatic tube got loose or for some other reason that team lost air pressure, the team would be unable to deploy their minibot. The minibot itself was still functional, but useless since it couldn't be conveyed to the pole. Same case here. The mechanism itself may be passive, but the system by which it is deployed may have a chance of failure.

Re: Why go over the bump
 

Right, but if you're positioned so that they can't touch the balls without touching you, and your robot does not move, you're in the clear because you're not causing the penalty by hitting them.

I honestly don't think it's a winning strategy, but it's possible that it could be in some circumstances, and thus teams should be prepared to face it just in case.

It may come as a surprise but no one person is the sole arbiter concerning what opinion is relevant and what is not. All strategies are essentially opinions. Is this kind of problem solving approach what mentors want to be teaching students?

Re: Why go over the bump
 

From a strategic standpoint, going over the bump allows for more mobility, and if you could design it in with relatively little effort, then it's a no brainer.

One of the most important pieces of advice I heard was that crossing a steel bump was dramatically different and harder than a wooden bump. Shaker's limited testing had difficulty even with the wooden one. With our build schedule and design process, we abandoned it.

There are a lot of aspects of this particular game that make the midfield barrier interesting. Recall the last time we had zone play with a ball supply nearly as limited. I see stronger parallels between this game and Breakaway than the free-roaming nature of Aim High. If you're good enough at what you specialize in, a combination of good strategy, great execution, and healthy use of alliance partner assistance will take you far.

Re: Why go over the bump
 

You seem to have taken personally something which was not. I apologize.

My point was that feeling should not get in the way of fact, and if in fact the strategy is even potentially legal, it is better to plan for the eventuality than to dismiss it. And yes, that is absolutely something I would like my kids to learn.

Re: Why go over the bump
 

I am not offended - no worries here. But when one apologizes, it is normal/genuine to do so w/o caveats

"Moving or positioning a Basketball to gain advantage is considered actively controlling. Examples are..." The bizarre "protect the balls in the corner" strategy is not enumerated in the examples but that does not make it legal. The GDC can't cover every crazy possibility, nor should they have to. In my opinion, the intent of this rule is beyond question. If one (with intent, not accidentally) put 4 balls in the corner and parks in front of them, you are controlling them - period. Further I think most refs would red card (per G45) a robot for repeating this offense.

Feelings (aka integrity, sportmanship and ethics) play a unique role in the engineering world. It is simply not possible for a customer to create a SOW or reqs that cover every possible design flaw or feature. It is ethical to point this out to the customer and (if there no cost/schedule impact) to act in accordance with the clarified intent of the design. This is the proper path for an ethical young engineer - might as well start teaching them (and setting the example) now.

This question is on point and the GDC did NOT choose to reply. As I said above they can't comment on every silly scenario.

Q. Do balls positioned behind a robot but not touching it, previously put there by the robot or an inbounder, count as being controlled?
A. Hypothetical game situations are highly context dependent. It is not practical for us to provide definitive answers for all individual situations which may be presented.

This question is also on point and the GDC reply is definitive (says my son the lawyer ;o). "Intent" is key.

Q. Is G45 violated if a robot herds balls into their alley and waits nearby so if/when an opposing robot attempts to retrieve said balls they can contact them resulting in a foul as per G44?
A. Yes. It could also be considered trapping depending on how the strategy is executed.

Re: Why go over the bump
 

I think this strategy is far from "bizarre, crazy, and silly". Game piece starvation and hoarding has been used frequently in previous game (2011, 2009, 2008, 2006). The only time ethics even came into the conversation was in Galileo 2008, when robots couldn't possess their opponent's trackballs and obviously tried to.

Re: Why go over the bump
 

I refer you to the rules cited above. There is no reasonable room for disagreement.

Re: Why go over the bump
 

I don't see any rule that prohibits a robot from sitting in its own ally while in contact with no balls as long as the robot makes no attempt to contact an opposing robot.

Per the blue box in G22 (see below), a robot is 'trapping' and thus controlling balls only when the ball is pressed up against their robot and the wall. Blocking opposing robots from getting access to balls is not trapping nor controlling.

"Moving or positioning a Basketball to gain advantage is considered actively controlling. Examples are “carrying” (holding Basketballs in the Robot), “herding” (intentionally pushing or impelling Basketballs to a desired location or direction) and “trapping” (pressing one or more Basketballs against a Court element in an attempt to shield them)."

Re: Why go over the bump
 

I'd say that one of the most extreme examples of this was 469 in 2010.

Re: Why go over the bump
 

The apology was that what I said seemed to have been misinterpreted as a personal statement. It was not, so the fault may well be mine.

That has nothing to do with the argument, and I stand by my statements. You are of course free to disagree.

Re: Why go over the bump
 

With all due respect, let us make a Socratic inquiry - how many examples (pro and con) are necessary to perfectly clarify G22? 3 (as above), 13, 133?... the pro and con examples in the blue box are NOT exclusive, they are one or three of many. So back to intent - the first sentence clearly, in my opinion, conveys the intent. Further, the second Q&A above leaves no room for interpretation. In my humble opinion, anything else is a tortured interpretation.

Lets agree to disagree. Perhaps week 1 will reveal the referees reaction to such strategies.

Re: Why go over the bump
 

Q. Do balls positioned behind a robot but not touching it, previously put there by the robot or an inbounder, count as being controlled?
A. Hypothetical game situations are highly context dependent. It is not practical for us to provide definitive answers for all individual situations which may be presented.

I understand the GDC's reasoning behind this answer, and as it stands right now, situational calls like this will be very much at the discretion of regional (and district) head referees. I don't think it's something we'll see often, but it will happen and I'm curious as to how it will play out.

Re: Why go over the bump
 

I don't think he was referring to machines, though obviously much of the brilliance of 469 was the necessary-and-perfect starvation strategy via their mechanical design.

If you look into 2009, 2010, and 2011, all of the games placed strategic importance in game piece management and "starvation".

In 2009, ball management was the (non-human player) key to the game. You could see this with the mid-season development of the human load autonomous - a far more reliable way for many teams to convert 20 balls into 40 points than simply letting human players take shots. Balls on the ground were in no team's control, and at the highest levels of competitive play, everyone that year had the same intake style by nature of the rules.

In 2010, it was highly advantageous, nearly as much as actually scoring, to move game pieces into your protected zone. Only one opposing robot could handle any game piece in that zone. Combine that with the limited number of game pieces and you can see why many teams started the match in the back and advanced gradually to the front as the match continued. Redirectors were simple additions that made MANY teams dramatically more competitive just by sitting in front of their ball return, preventing scored balls from returning to neutral territory.

2011 didn't play out exactly as I thought it would, primarily with teams that trained human players to the point of throwing past midfield. But listen carefully to the words of Blair on Einstein Semi-Final 1. "Looks like the starvation strategy..."

It's going to happen as much as the rules, referees, and teams allow it to. Prepare.

Re: Why go over the bump
 

Thank you! I totally agree with you. My team spend almost 2 weeks brainstorming and strategizing. We decided we wanted to be a 100% self reliable, meaning picking balls from the ground, going over the bump and the bridge, being able to balance and shoot from different places and angles, that way we had a better chance of playing defense and moving everywhere whenever we wanted to.

It's important to remember that there's only 1 bridge and 3 robots... wouldn't it be nice that someone in your alliance could go over the bump? One must always be a step ahead of the game. Things break, batteries die, robots will not always have balance. STRATEGY is the key... within the rules there's always a different way to play the game, you just gotta keep your eyes and your mind wide open;)

"Scientis study the world as it is; Engineers create the world that has never been" Nerdy&Proud<3

Re: Why go over the bump
 

because bridge ball deflectors may not actually deflect balls like it has been happening at competitions for the past 2 days :ahh: