Should FIRST address "ramp bots"?

[MattB703]

Something has been bothering me since I spectated at GRL in the second week of regionals, but I wanted to wait until competition was over to bring it up. It seems like there is an alarmingly large number of teams this year who have started either making angles sides/front/backs on thier robots or have added flop down type ramps. I am sure that the intent of these teams was purely for defense so that their robots could not easily be pushed around. It is a very effective strategy and I am sure that I am not the only FIRSTer to have taken note of it. I think that our FIRST community is now faced with one of two choices;

A. Do nothing and expect that the majority of teams next year will have some sort of angled ramp sides, possibly resulting in a much higher incidence of tipped over robots.

B. Petition FIRST to make a rule for next year limiting the angle of any side of the robot.

Please let me know your thoughts on these choices or if I have missed an option.

Thanks
Matt B.

[Kevin Sevcik]

I'm not convinced B is a viable option. We have enough rule bloat as it is without that rule. I can already see problems. What if the angled side of the robot has a legitimate function related to the game? How to you judge flop bots? What if it's a curved surface? What if it doesn't go all the way to the floor?

Ramp robots are just a reaction to brick bots. Teams know that flipping other robots is unacceptable, so ramp bot driver will be careful. Other robots defending them just need to take the ramps into account. Possibly there will be countermeasures developed to make it possible to push ramp bots anyways.

[Eugenia Gabrielov]

I think that this answer can be split into a few parts.

1) Outriggings

You see them everywhere: material is used (within the "box" so to speak) that folds out once the match starts to allow the robot to maintain balance and defend itself from tipping. I feel that these are appropriate as engineering aspects of the robot and should stay. Also, it's hard to decide how you'd regulate them.

2) Sloped sides

Many of the effective bots I've seen this year had sloped sides that helped with both the balance, defense, and overall imagery of the bot. An excellent example is 67. I assume that is the type of the robot you mean, with a base geometrically designed for that kind of balance. I think these are appropriate provided they remain within the box, which 67 among others does uniquely. I know there were a few bots that didn't pass inspection with their riggings and slopes. Since there are rules against ramming/spikes, it'd be good if you could explain the connection you have here. I think that's the main concern, but I'm not sure.

3) "Ram" sides
Some sides are designed specifically perhaps to throw other robots off balance. It is an offensive tool. I don't feel comfortable making judgement on a team for that strategy. As far as angle goes, what is appropriate, and what isn't? I think you have a few good ideas here to keep things flowing well on the field, but at the same time it adds a whole new aspect of change. I think that in 2006 the game will be designed to address this structure interest, and robots will be built and geared to it. :) Good luck with considering proposing this to FIRST rulemakers, if you choose to. These are just some thoughts on the subject.

[Josh Hambright]

I dont forsee ramp bots going away anytime soon. Its a good defense against brick bots that only serve the purpose of pushing because it makes it much harder for them to be able to push you. Teams have been using slopped sides to deter pushing for years.
Anyone else remember when 111 had a robot drive right up on top of them at MWR this year?

[Cory]

I've made my feelings on this clear before, and I'd like to point out an instance which I've cited several times.

Wildstang 2003, drives out in auto, 226 drives up their ramps, gets stuck. They could have easily tipped them, but backed off and allowed 226 to go on their merry way. Most teams who have ramps/sloped sides/wedges are using them like Wildstang did in 2003, to deflect pushing forces away from the robot, not to maliciously tip them. And it works. Who thinks Stang would have won nats in 2003 without their wedges?

It's a very smart engineering fix to allow a robot without a powerful drivetrain to hold position over other robots, and should be commended rather than looked down upon.

[abeD]

I agree with Cory. Angled sides when used correctly should not be penalized. I also think that the rules would allow a ref to make a judgement call based on the intent of someone using a ramp to flip someone. The key is once someone drives up onto your ramp/angled sides not to push back quickly as that will definately result in a tip, just back off or don't move.

[David Brinza]

Having ramped sides to a robot is a decisive DEFENSIVE advantage. The opposition takes a considerable risk of flipping themselves if they attempt to ram a robot with ramped sides. FIRST allows teams to push low on opposing robots. If you push (or pull) high on a robot and cause it to tip you are subject to disqualification (man, how I know that :( !). If you position a ramped feature under an opposing robot then lift it causing the robot to flip, you can be disqualified: see rule <G25>.

I say let there be ramp bots and let the opposition learn how to deal with these robots. The ramps certainly are deterrents to high-speed ramming and ramming is a part of the game FIRST strongly wants to discourage.

[MattB703]

Wow!

I feel so lonely in my opinion.

I do realize what a powerful defensive strategy having ramp sides is. That is why I'm predicting that there will be so many of them next year. I have also seen enough Battlebots to know that a good drivetrain and a wedge shape can make a powerful offensive strategy as well.

Lets say you make a robot design to play next years game and you put sloped sides all around it to protect yourself from "brick bots". For whatever reason your scoring concept does not work as well as the team had envisioned it to. It soon becomes clear that the best contribution that you can make to your alliance is to get in the other teams way and slow down their scoring to allow you partners to outscore them. You play several qualifying matches and this strategy is working very well, them you have the match-up against this year's uber-scoring robot. You driver is trying to block them and is playing a very good game but the uber-bot is dancing circles around you with its awesome "hover drive". Suddenly uber-bot is on its side. Did your driver press the sticks forward a little while they were mixing it up? Is it the uber-bot's fault because they drove up on you? Do we ask the refs to make a judgment call? Weren't the judgment calls by the refs a lot of the problems people had with this year's game?

I'd like to avoid the whole scenario above.

[Denman]

i must say that i agree with the majority here that they are a viable defensive option. however i have seen a superb bumper design on another robot. Did anyone see the bumpers on694's bot? They were designed so that when a bot hit them they would move back and reduce the force on them. I can't see any photos though... i'll have a look on my computer at home later

[Al Skierkiewicz]

I will be the first to weigh in here but the design idea was Raul's. When you can get up 14.5 ft you need to widen your base for stability. If we had a few more pounds to work with, you would have seen additional devices to prevent tipping I expect. Not every year would require outriggers but this year it did. (2003 was simply to protect the "ice" since we couldn't anchor down on the HDPE) In addition, most robots need some protection from those teams who design a strictly defensive robot who can do nothing but push other robots around and we got pushed a lot. Thankfully many of those times were noticed by referees and called as needed.

[Denman]

good point
however keeping a low centre of mass is also a good way to keep yourself from tipping. We added stuff to keep us as near to the limit as possible and with the lowest centre of mass, however i still managed to flip the bot in practise rounds ... it got jammed on a tetra and fell...

[Al Skierkiewicz]

Carrying two 8.5 pound tetras at 14 feet is a big force to overcome.

[MattB703]

One thing to consider is that outriggers don't necessarily need to have sloped sides.

[petek]

Maybe I'm looking at this too simplistically, but rather than limit engineering designs, I would prefer that FIRST instruct referees to penalize a team which, while in the process of pushing on another robot, causes it to fall over. This would apply to any shape of robot and would not penalize the "ramp bot" unless it was driving into the tippee. It would make it a penalty to push a robot up the side of a wedge (e.g. this year's goals) until it tipped over. This would not penalize a robot if the two got tangled up and, while trying to get un-tangled, one of them tipped over, unless the tipper was pushing against the tippee. Also, it would not penalize a robot if the tippee was doing the pushing or ran into the side of the tipper accidentally.

Am I missing something?

[MattB703]

The only thing that concerns me about that approach is that the ref needs to decide if a robot is pushing or not.

[Al Skierkiewicz]

One thing to consider is that outriggers don't necessarily need to have sloped sides.
Why? Sloping the sides directs the down forces to a higher part of the robot and significantly reduces weight.

[abeD]

The only thing that concerns me about that approach is that the ref needs to decide if a robot is pushing or not.

You bring up a good point...but sooner or later at some point in almost every match a ref will have to make a decision. This is almost inevitable.

[Rich Kressly]

Any robot in any configuration can be used in the "wrong" way. It's a difficult thing to do, but you need to walk a mile in another team's shoes before deciding a particular design is always bad. Teams like 111, who have proven track records, get a lot of "attention" from opposing robots on the field. Designing ways to deflect force away from the robot so it can still move around and perform tasks is smart in my estimation. This is vastly different than a robot designed only as a wedge (that can perform no other offensive task) or a team that uses sloped sides to "attack" another robot.

I'm not concerned with too many flipped robots at all. This is the third straight year I've seen a significant amount of bots with sloped sides and each year I've seen fewer flipped robots than the year before. In 2003, with that ramp on the field, seeing capsized robots (even in autonomous) was much more common than what I saw this year. I've also seen teams that have been able to use arms/appendages to get back up after falling over. Some of these occurances have been some of the most exciting matches I've seen.

[BillP]

I think that the ref's at Nationals did an excellent job of addressing this whole issue at the driver's meeting before the competition. They stressed that "ramp-bot" drivers need to be very careful because they would be scrutinizing very carefully the actions of any robot with sloped sides. Their basic opinion was that sloped sides are not (currently) against the rules, but intentionally tipping another robot was. Because of this, the seemingly innocent actions of a slope-sided robot could easily be interpreted along the same lines as ramming or pushing high on another robot.

There were several excellent robots with sloped sides in Archimedes (980 comes to mind), that never had any problems because of the skill and care of their drivers. In a nutshell, the ref's defused the entire situation before it even started.

OK, now to answer the question: There should be no rules limiting the slope on the sides or robots (IMHO).

[Padfoot Black]

FIRST needs to look at it case by case, they should allow the wedge type robots, but when a team uses it with the intent to flip another robot, it needs to be fixed. During one of our Archimedes matches, we were playing defense on a team (they will remain nameless) who had a wedge type design, my driver knew he could flip himself and did everything not to. But when we were at the perfect angle with the wedge, the other teams driver pushed us into the loading zone,we drove in reverse to try and stop him, he then watched our robot tip up a little and then backed up a lfew feet, and drove straight into us and flipped us into thier loading zone. FIRST disqualifyed the team from that match, I feel it was the right call, but next year first needs to discover these designs in the regionals, and make sure teams know that they cannot use them to flip another bot.

[Dave Flowerday]

How is building a robot with ramps on the side any different than building a robot with 6 motors on the drivetrain? I've seen both types used to tip over other robots (in fact, I think I've seen more tipping done by robots without ramps, because those with ramps are usually playing offense, not defense).

For those teams who prefer to play offensively by manipulating the game pieces, ramps are one of the few protective measures they have against teams who prefer to play defensively and constantly push everyone around.

[Mike Ciance]

i've been pretty angry about wedges for a long time. i was actually thinking of starting a thread like this. glad to see that i'm not the only one.

nearly every year i've been involved in FIRST - 3 out of 4 - i've seen wedge robots that were built with the obvious intention of getting under other robots and pushing or flipping them.

wedges give robots a clear and unfair advantage. shouldn't a pushing match be decided by the strength of the drivetrains, rather than who makes a cheap shot?

we put a lot of work into our drivetrain. nobody could push us back... as long as we had all our wheels on the ground. on friday at nationals this year a wedgebot got under us and pushed us halfway across the field with little effort. at both of the regionals we attended we saw other teams getting pushed around by wedges.

in this game and in games of the past there have been robots with wedges that obviously have no function in the game itself. what reason is there for a wedge other than to get under other robots? wedges are just as unfair as pinning, and i can't imagine why FIRST hasn't already made rules against it.

rep me how you want, i stand by what i've said

[Greg Needel]

FIRST does not like to make rules dealing with specific robot design (look at the Q&A) i think it basically comes down to the individual team looking at the rules and the strategy they want to play. if they build a wedge bot and get DQed on intentional flipping they knew the rules when they build the bot and have to deal with them. but if they just play very effectively against you and use the advantage of the wedge then i see no reason to limit the creativity of a team's design for a problem that "might" occur once in a while. for this same reason there was never a rule on how you could pick up tetras this year

[Dave Flowerday]

we put a lot of work into our drivetrain. nobody can push us back... as long as we have all our wheels on the ground. on friday at nationals this year a wedgebot got under us and pushed us halfway across the field with little effort. at both of the regionals we attended we saw other teams getting pushed around by wedges.

in this game and in games of the past there have been robots with wedges that obviously have no function in the game itself. what reason is there for a wedge other than to get under other robots? wedges are just as unfair as pinning, and i can't imagine why FIRST hasn't already made rules against it.So you want to be able to push anybody around that you please, and you want FIRST to make a rule requiring that teams have a good pushing surface for you to make contact with?
we put a lot of work into our arm. nobody can score faster than us... as long as we have all our wheels on the ground. on friday at nationals this year a drivetrain-bot pushed us halfway across the field with little effort. at both of the regionals we attended we saw other teams getting pushed around by drivetrain-bots.

in this game and in games of the past there have been robots with massive drivetrains that obviously have no function in the game itself. what reason is there for a massive drivetrain other than to push other robots? drivetrain-bots are just as unfair as pinning, and i can't imagine why FIRST hasn't already made rules against it.
I imagine my slightly modified quote here sounds ridiculous to you... and that is how your statement sounds to those of us who don't put all our effort into a drivetrain.

[Beth Sweet]

We had a "ramp bot" this year. We called it "offensive defense." Basically, our idea was that we were going to use GP on the field (as expected) and not drive up to a robot to flip them. Our ramp was so that if we were trying to cap and another machine tried to play defense on us, that all that they could do was to drive up on us and give us a little extra weight to help out our CG. We foresaw a number of machines this year going defensive and decided that we had to protect ourselves. We aren't going to go and attack another machine with it, but you had better bet that if we get attacked while playing our game that we will defend ourselves.

[Kevin Sevcik]

To those that are annoyed with not being able to push around ramp-bots: This is the whole point. The people designing ramp-bots don't want to be pushed around, and have taken steps to ensure this. If you feel it is utterly necessary to your strategy to push them, then by all means engineer yourself a solution to the problem. I've thought about it for about an hour total and already have two possible solutions for a pushing robot to defeat a wedge. They would have the added advantage of making your robot less tippable from things getting under it anyways.

[petek]

I still maintain it is the robot driver's and referee's actions which should be dealt with, not the physical design of the robot. This year's game may have emphasized the issue because of high CGs.

The problem I saw this year was inconsistent refereeing. Between regionals and even between ends of the field at Atlanta, I saw cases where blatant battlebot defense resulted in robots being tipping without penalty, contrasted with robots being penalized when another robot fell over after running into them (where the penalized team was clearly blameless from my perspective).

To me, this says that FIRST needs to do a better job of making the rules clear and ensuring that the referees fully understand the letter and intent of those rules.

[DarkJedi613]

wedges give robots a clear and unfair advantage. shouldn't a pushing match be decided by the strength of the drivetrains, rather than who makes a cheap shot?

we put a lot of work into our drivetrain. nobody could push us back... as long as we had all our wheels on the ground. on friday at nationals this year a wedgebot got under us and pushed us halfway across the field with little effort. at both of the regionals we attended we saw other teams getting pushed around by wedges.

in this game and in games of the past there have been robots with wedges that obviously have no function in the game itself. what reason is there for a wedge other than to get under other robots? wedges are just as unfair as pinning, and i can't imagine why FIRST hasn't already made rules against it.How does it give an "unfair advantage"? As long as anyone can put a "wedge" on their robot it is not unfair. I don't see how you can say that since your drive train is more powerful that someone shouldn't be allowed to create a design to deflect the force from your robot. I believe our robot was the one that pushed you across the field on Friday. We designed the front and back of our robot as a sloped angel (I think 48 degrees from the base) for the sole reason of deflecting force. Last year we had some robot ram us and damage parts of our frame, by putting a sloped front on the robot a portion of the momentum of a robot is pushed up off the frame, and the rest is spread out throughout the entire frame instead of having two bars on the back take all the force (and most likely bend or break). If we had designed it to flip you, you would have been flipped, but instead we just pushed you back so that we could get to our loading zone.

I agree that the problem is not in the robots, but in the way they are driven.

[Evan Austin]

I see no problem with a ramp bot and if I was worried about other teams having them I would try and figure out some way to work around it. I think it can be a good thing because, as other people in this thread have said, it reduces the force acting against the robot. In years past I have seen robots get severely damaged from taking a hard hit. If the ramp can help reduce these forces, I would be in favor due to the decrease in damage to the driveline and other parts of the robot.

[Andy Baker]

i've been pretty angry about wedges for a long time. ...
wedges give robots a clear and unfair advantage. shouldn't a pushing match be decided by the strength of the drivetrains, rather than who makes a cheap shot?

we put a lot of work into our drivetrain. nobody could push us back... as long as we had all our wheels on the ground. ... what reason is there for a wedge other than to get under other robots?

The main reason teams design wedges or wings on their robots is to provide themself a defense against a team who is ramming them. Many teams, including yours, rammed other teams in 2003. This was done to knock other teams from the HDPE platform during Stack Attack gameplay. Some teams rammed in 2004. Seeing teams make ramps or wedges on their robots is simply a passive defense against aggressive drivers who like to use their robot's momentum as a tool to play defense.

Now, if a ramp or wedge is used to get under another robot and continue to drive into them until they are flipped, then that is an illegal use of a ramp, imo.

Andy B.

[DougHogg]

There are also disadvantages to wedges.

We put wedges on the sides of our robot so that when we were trying to cap, opponents would have trouble tipping us or shoving us around. However in the Archimedes quarter finals, our wedges worked against us. We were defending a goal that we owned and pushed into a robot to stop them from capping. Unfortunately we tipped the opponent and our alliance was dq'ed (disqualified). That happened to us twice in the same quarter final! However one of the opponents was also dq'ed for tipping in one of the matches making it a tie (both alliances dq'ed). We finally won the quarter-final, but, needless to say, being dq'ed twice in one quarter final didn't make our day. :(

The Archimedes referees were very strict about tipping if a robot had a wedge, and they didn't seem to have any trouble making a ruling. In our case, we were moving forward with a wedge, the opponent tipped, and we were dq'ed. I don't have any disagreement with their ruling. My point is that having a wedge is helpful when being pushed but obviously not helpful when you are doing the pushing and it gets you dq'ed.

On the positive side, this year, we saw some robots come at us so quickly that they caught some air when they hit our rear wedge and flew over us. We were happy that our robot didn't have to deal with the collisions that would have occurred if we hadn't had wedges.

I do think that the rules on pushing with a wedge need to be clearly spelled out (ie if you push with a wedge and a robot tips, you will be dq'ed) as the rules were applied very differently at different events.

Doug Hogg

[Goldeye]

i must say that i agree with the majority here that they are a viable defensive option. however i have seen a superb bumper design on another robot. Did anyone see the bumpers on694's bot? They were designed so that when a bot hit them they would move back and reduce the force on them. I can't see any photos though... i'll have a look on my computer at home later

Sadly, the bumpers weren't as effective as we would of liked. The idea was amazing, but we didn't implement perfectly. I'd like to try it again next year myself. We ended up reducing the bumpers to not come out, and just remain as cushioning. We replaced one side with a rather steep flopout wedge, but since it didn't go all the way to the ground, it never came close to flipping anyone, and we were careful not to push too much with that side.

At any rate, the bumpers have absolutely no effect on a wedged bot. One such robot flipped us over in the qualifying rounds, pushing us into a vision tetra untll we tipped. This team went on to topple several robots in the elim rounds, just barely losing in the elims. Wedges are all fine and dandy, but a team with a wedge should be responsible if they flip a bot over as a result of that wedge. It leaves room for a judgement call, but a very clear one: If they're pushing with their wedge and a bot falls, they get DQ'd. The rules prohibit putting a part of your robot under another bot and lifting, and what does a wedge do except lift as it moves foward?

There's nothing wrong with a wedge to have your bot "hold" another and transfer weight, but when you make it too steep, you're lifting, not holding.

[MattB703]

Doug

I agree with your last post completely. I am only concerned that the refs will need to determine if the wedge shaped bot was pushing or being pushed when the tipping incedent occured. This will not always be an easy call and not everyone will take their DQ as graciously as you have.

Matt B.

[Lil' Lavery]

It all depends on the ramp and how it is used. Some ramps are great defensive tools, and do help center of gravity, but some are excessive or prove to be a tipping hazard. While Im sure 233's sloped edges were made for defense, I saw them once push another robot down, and heard they did at least one other time. Im not sure if they would have tipped these robot's anyway, but the ramps looked to be a very definate help to the tipping. Im also positive that they werent used intentionally. The tip I saw was during autonomous and of their own teammate.
Ramps that prove to be dangerous over the course of competition should be adressed, but not all ramps. If a team developes a record of using the ramp aggressively or of its ramp flipping other robots on several occasions that team should be instructed to do something about the ramp.
While ramps are often the simplest solution to opposing "bricks" and CG issues, their are countless others. Outriggers dont have to be ramps. in 2004 we had a "wheelie bar" that prevented us from tipping while climbing onto the platform to hang. This year Team 118 had small PVC tubes that curved down to the floor (they started parallel to the floor, and curved until they were perpendicular, so they couldnt be a ramp nor ramming spikes) that helped keep them from tipping. Also, our drive system this year was fantastic from keeping us from tipping.
For those who havnt seen it, it is a holonomic drive system, but instead of the wheels being mounted vertically along the 4 faces of the robot, they are mounted on a 20 degree angle in the 4 corners, allowing our "footprint" or Conservative Support Polygon to be as large as possible, as well as lowering the drive systems CG. Because of that, we never even came close to tipping. Also, by avoiding massive, heavy arms, ect. you significantly lower your CG.
As for defense against brick bots, there are a number of bumper designs that can beat them. Also, just having a faster, more maneuverable, or stronger robot will often do the trick. "Cattle plows" or designs that drive with a leading corner will also usually deflect the blow. Outriggers, or some form of device to "plant" you to the ground can be highly effective for holding ground against powerful bots as well (like the top of the ramp in stack attack, or the top platform last year). High traction drive systems, like many tank treads, can do a great deal to hinder bricks as well.

[EricH]

Please note that my team used wedges as defense...
I think that wedges are great as long as you know what you are getting into. 2003: We used wedges to hold us on the platform and to make sure we didn't slip backwards on the ramp. As long as you came up elsewhere or backed off, you were fine. If you came up on us and tipped, and we hadn't moved, that was your problem.
2005: Side wedges. If you saw us (and most of you probably did) you know that we only had one that could possibly be used as a tipper by us. If you came at us from the side, and you tipped (as one robot did in practice), that was your problem. In back, maybe or maybe not. And at least one team (number withheld) got up the steep side wedges hard enough to damage acrylic panels pretty badly.

However, there was one robot at L.A. Regional that was a low box with four wheels and a wedge that lowered. They were careful not to draw penalties, and that is good. However, at least once they lifted a goal. Not good.

Use of wedges depends how they are used. Tip a robot or two deliberately and get DQ'd. Accidentaly and get a warning.

[Joe Ross]

I can't say I've seen more wedges/ramps this year then in years past. I can remember at least 1 robot with a wedge/ramp that went far in the eliminations at nationals every year since at least 2000, and most years it's a few. 67 was a great example last year.

If we ban one of the simple machines from being used, I think we should ban wheels as well. :)

[pyroslev]

2003: We used wedges to hold us on the platform and to make sure we didn't slip backwards on the ramp. As long as you came up elsewhere or backed off, you were fine. If you came up on us and tipped, and we hadn't moved, that was your problem.


History with a ramp:
In 2003 we also employed small ramp-like fins. THey were meant to make a robot beach on us and hold the hill. However, a robot ran up the small 6-in or so ramp fins and flipped almost over end. (We got the play of the day for that award by the way.)

Ramps are useful for many facets in many ways. To ban them would take the fun out of it. Just have the driver watch his CoG when near a ramp bot and it'll be okay.

[Jeremiah Johnson]

At both regionals I attended this year (St Louis and Midwest) I saw angled designs. At St. Louis there was a robot that was not made for the intention to tip robots. But when they found out that it was very good at it they did. I told the driver multiple times that this is not "battlebots" and it was totally against GP. We were paired with them twice. Thankfully they got hung up on tetras and didnt have the chance to tip any during our matches. At Midwest the intent was just the opposite. 111 had a suppubly designed robot. There slanted design was used in the exact same way ours was: stability. When they had their tetras up so high, just a tiny nudge would have sent them over. It was just an innovative design and weighed much less than ours. I am totally against the intent to disable a robot, just like the major majority of all FIRST participants.

[dhitchco]

This was my first year at FIRST.

During the regionals I saw "ramped" bots a lot. I also saw "headless" bots that were just there to provide mayhem and defensive "bashing". In fact, our own robot turned a corner too fast and we actually flipped ourselves by running up the ramped side of another bot.

BUT....at the finals in Atlanta, all the robots and their drivers/coaches knew enough to take a positive offensive stance. Each robot tened to its own area of the field like a finely choreographed dance. So whether a robot has "ramped" sides or whatever design is a MOOT POINT when you get to the teams that really know how to properly play the gam for maximizing the score. They don't waste time with defensive moves!

Next year's robot will be a "sheet of paper"; impervious to anyone elses intentions....ha, ha, ha

[Ken Patton]

During one of our Archimedes matches, we were playing defense on a team (they will remain nameless) who had a wedge type design, my driver knew he could flip himself and did everything not to. But when we were at the perfect angle with the wedge, the other teams driver pushed us into the loading zone,we drove in reverse to try and stop him, he then watched our robot tip up a little and then backed up a lfew feet, and drove straight into us and flipped us into thier loading zone. FIRST disqualifyed the team from that match, I feel it was the right call, but next year first needs to discover these designs in the regionals, and make sure teams know that they cannot use them to flip another bot.

Hmm.

I was coaching the other team. From my vantage point, you guys drove up on us (well onto the wedge), and we chose to drive forward. My intent was to get us to touch the LZ with you perched on top of us. I never saw you try to avoid the contact by driving in reverse (that would have put you in our loading zone and drawn a 30 pointer). We certainly never backed up. We went too far by pushing after you hit the field border - you tipped (right into the border, not into the LZ), and we (rightfully) got shut off.

In hockey terms, we tried to pull a Fedorov (taking a fall to get a call) but ended up pulling a Probert. We learned our lesson.

Ken

[Brandon Holley]

Our team (11) used wedges for the first time this year, and we are sure glad that we did.

Our wedges were actually a controversial topic around week 5ish. Some of you might remember we have the aluminum "picture frame" wedges. They turned out to work great. The way we designed them, there was a good 3/4" pushing surface before the wedge started. Our wedges were one of our greater parts of the robot this year. I know many teams have had bad experiences with wedges, but they have to understand that the wedges dont come without sacrafice...

After week 1, at EVERY SINGLE drivers meeting, the topic of wedges was brought up. We learned real quick that we had to be careful with our as some people saw them "tipping weapons". The truth is that the few times we had to flex our drive train muscle, the wedges gave us the advantage we needed. A couple of robots were flipped, but none of them because we drove into them and they flipped. Other teams pushed them into us, they hit us at a high rate of speed...etc.

A note to the teams who are disgruntled about wedges...If you really can't stand them being used against you, why dont you try using them yourselves?

[Greg Marra]

This is an issue that could be addressed in game design. It seems to me that a robot with sloped sides would have trouble getting onto a raised platform; ala the 2004 game.

[Alan Anderson]

...next year first needs to discover these designs in the regionals, and make sure teams know that they cannot use them to flip another bot.Teams should already have known that from Kickoff day.
Strategies aimed solely at the destruction, damage, tipping over, or entanglement of ROBOTS are not in the spirit of FIRST Robotics Competition and are not allowed.

[MattB703]

A note to the teams who are disgruntled about wedges...If you really can't stand them being used against you, why dont you try using them yourselves?

I intend to. I wanted to see what the community thought. I'd prefer no wedge bots, but if there is no rule against it next year we will have sloped sides added to our bot.

[Brandon Holley]

I intend to. I wanted to see what the community thought. I'd prefer no wedge bots, but if there is no rule against it next year we will have sloped sides added to our bot.

Unless of course the game FIRST designs this upcoming year would deter teams from using them. All I know is for us they worked great, and Im sure other teams that used them for the first time this year would agree 100%.

[Lil' Lavery]

A note to the teams who are disgruntled about wedges...If you really can't stand them being used against you, why dont you try using them yourselves?
That puts us in what is more or less an arm's race, but with wedges. Who can make the best wedges without becoming a hazard to breaking the rules. If all the teams start using wedges to avoid being tipped by wedges, whats the point of them in the first place? At that point, why not just say no wedges? :confused:

[Allison K]

That puts us in what is more or less an arm's race, but with wedges. Who can make the best wedges without becoming a hazard to breaking the rules. If all the teams start using wedges to avoid being tipped by wedges, whats the point of them in the first place? At that point, why not just say no wedges? :confused:

Because then you open up a whole new can of worms...exactly what angle is considered a wedge. ;)

I don't recall seeing any incidences of wedges tipping other bots this season. It was such an offensive game anyway.

My team (since I've been on it) has never built a wedge bot. The only time I recall having an issue with one, was in 2003 when 111 was defending their stack and we drove up on them at some odd angle so that our treads were no longer making contact with the ground and we couldn't move. But that was our fault not theirs.

[Mike Soukup]

As soon as FIRST does something to prevent 'boxes on wheels' from repeatedly ramming us, we'll remove the wings & ramps, until then we need to protect our robot and our chances of being successful in the game. The teams whose sole strategy is ramming and pushing have brought this upon themselves. Teams get fed up with being a whipping post for the rammers so we have to take action. If you want to be able to push teams across the field or ram without flipping yourselves, come up with a new strategy or design to beat the ramps. We've found a way to deflect the blows, now it's your turn to innovate and come up with something new. Come up with a better way to play defense that doesn't rely on ramming and destruction.

To me the complaining coming from the rammers & pushers just sounds like sour grapes. You want to show off your perceived power and other teams come up with a simple and effective way to prevent it.

wedges give robots a clear and unfair advantage. shouldn't a pushing match be decided by the strength of the drivetrains, rather than who makes a cheap shot?
I guess the answer depends on perspective. I think the winner of a pushing match should be decided by the entire robot (wedges and all), not just the drive train.

[dlavery]

If we ban one of the simple machines from being used, I think we should ban wheels as well. :)
Actually, that will fit in rather well with the planned "no fasteners" rule for next year...
This is an issue that could be addressed in game design. It seems to me that a robot with sloped sides would have trouble getting onto a raised platform; ala the 2004 game.
Of course, the other way to address it is to design a game where sloped sides are REQUIRED on every robot! Then everyone would be on the same level playing field (or sloped playing field, or whatever) :)

-dave

[EricH]

I don't recall seeing any incidences of wedges tipping other bots this season. It was such an offensive game anyway.


Wedges have tipped robots, but for the most part they brought it on themselves. I did not see this match, but I heard about it: Newton 2005. Practice (which is supposed to be minimum contact): 1595 and 330 start mixing it up on the field. 1595 goes up 330's side wedge and flips over.

If you don't like wedges, live with them until they are banned. Box-bots with strong drivetrains or robots assigned to play defense stay away from the wedges on other robots, they don't tip. They go up the wedges and tip, whose fault depends on where the wedge is (side, front or back) and who is pushing.

I personally have no problem with wedges. Robots with them are more stable and if they are tipped, someone probably pulled them over or they went up a surface that was too steep. Robots without them can avoid the ones with them. And, if you can't beat 'em, join 'em--if you have the weight.

[Justin]

OR we could go back to better time in FIRST history when the policy on tipping was basically you shouldn't tip intentionally but if tipping does happen and you're the robot being tipped you had better design your robot to withstand that. Accept the fact that you are going to be tipped at a competition and build your robot accordingly...no problem. Also realize that audiences love to see robots go over. I think that the policing got well out of hand this year by the time we got to nationals where was almost no area on the field you could maneuver without risking a penalty and if you flipped someone look out you were either going to get a 60 point penalty or nothing at all depending upon which division you were playing in. How about everyone build some robust robots and we let things happen as they will instead of trying to play police and make sure nothing bad ever happens on the playing field.

Justin

[Al Skierkiewicz]

OR we could go back to better time in FIRST history when the policy on tipping was basically you shouldn't tip intentionally but if tipping does happen and you're the robot being tipped you had better design your robot to withstand that. Accept the fact that you are going to be tipped at a competition and build your robot accordingly...no problem. Also realize that audiences love to see robots go over.
Justin

Justin,
I don't remember any time in the past where it was acceptable to intentionally tip another robot. If not officially frowned upon it has been a hazard for humans near the playing field and for field pieces and therefore has not been allowed. There are other competitions where the field is enclosed. In that competition tipping is OK and encouraged.
I am in the audience and I do not like to see robots go down.

[dlavery]

I don't remember any time in the past where it was acceptable to intentionally tip another robot. If not officially frowned upon it has been a hazard for humans near the playing field and for field pieces and therefore has not been allowed. There are other competitions where the field is enclosed. In that competition tipping is OK and encouraged. I am in the audience and I do not like to see robots go down.

Just a quick history tidbit to throw in here. Many years ago in FIRST, tipping was not only accepted, it was actively encouraged (does anyone else here remember the infamous <Rule F7> from 1997?). Back then, part of Dean's introduction talk at the kick-off for each season included a statement that went something like "offense and defense are both parts of this game. This is a sport, just like football. Just like football, you can tackle the other players. But there are limits - you can tackle, but you can't clip. In this game, instead of tackling you can tip over other robots. And knowing that, you should design your robots accordingly - the potential for being tipped is part of the challenge. The well-designed robots will be able to deal with that, and will be able to get back up if they are tipped." As you walked through the pits those years, you could see all sorts of little devices that were incorporated into the robots that were specifically designed to lift up the edge of an opponent robot and flip it onto its back (one of the best that I remember was from Team 118 and the small, very effective flippers on each corner of the robot that Charley Price designed for the robot that year). Several of the mentors had a very long, very interesting discussion with Dean about the tipping ideas while sitting around the hotel at Disney in 1996. He made it very clear that tipping was part of the game, and he expected to see a lot of robots go over - and see a lot of them get up and continue in the game. The prohibition against intentional tipping did not come into play until, I believe, 1998 (or possibly 1999).

-dave

[Beth Sweet]

Many years ago in FIRST, tipping was not only accepted, it was actively encouraged (does anyone else here remember the infamous <Rule F7> from 1997?).

What I love is that Dave still remembers the exact rule title. That is an interesting little factoid Dave, though I'm not quite sure how destruction of your opponents robot fits into GP.

[RogerR]

What I love is that Dave still remembers the exact rule title. That is an interesting little factoid Dave, though I'm not quite sure how destruction of your opponents robot fits into GP.
if you'll take another look at dave's post, you'll see that in no way, shape, or form do they encorouge destruction of the opponent, but rather tipping (in a non-destructive manner, i assume)
Just a quick history tidbit to throw in here. Many years ago in FIRST, tipping was not only accepted, it was actively encouraged (does anyone else here remember the infamous <Rule F7> from 1997?). Back then, part of Dean's introduction talk at the kick-off for each season included a statement that went something like "offense and defense are both parts of this game. This is a sport, just like football. Just like football, you can tackle the other players. But there are limits - you can tackle, but you can't clip. In this game, instead of tackling you can tip over other robots. And knowing that, you should design your robots accordingly - the potential for being tipped is part of the challenge. The well-designed robots will be able to deal with that, and will be able to get back up if they are tipped."
i might be mixed up, but i thought it was rule T5 that allowed the tipping of other robots. i distinctly remember hearing/reading the posts of several rhode warriors that mention a decal on aquatread's flipper reading: "T5 is in effect".

[Ken Patton]

Some additional history....

It was 1998 when FIRST added the rule against tipping devices. In my opinion it was brought about by current team 121's awesome 1997 tipping machine. There were times when 121 would go out, tip one or two opponents (it was 1 v 1 v 1 back in 1997), and the go on to win the match. They were awesome, and totally legal. They didn't manage to tip us, but they did rip out a major chunk of our drive system in Orlando! We weren't quick enough to outrun them!

Back then it was the Naval Undersea Warfare Center, I seem to remember a motto "Death From Below." Yup, we were scared of 'em.

Ken

[Al Skierkiewicz]

Just a quick history tidbit to throw in here. Many years ago in FIRST, tipping was not only accepted, it was actively encouraged (does anyone else here remember the infamous <Rule F7> from 1997?). ...
The prohibition against intentional tipping did not come into play until, I believe, 1998 (or possibly 1999).

-dave
Well that is just about the time I started and only attended MWR in 97 & 98. Ken, I remember a huge controversy over the strategy of 121 that year. It seemed like that subject came up everywhere we went. It was a little more vocal than the rampbot discussion as I remember.

[Kims Robot]

Tipping is now becoming as controversial as pinning. Back in 1996 even pinning was legal... If I remember right, my team won Rumble at the Rock that way. Our robot wasnt awesome that year... and we got the number one ranked team in the nation backed into a corner of the hexigon, and held them there for close to 45 seconds of the end of the match. I can remember getting boo'd... but it wasnt against the rules then... it was a viable strategy, and we won that way.

I have no problem with wedge bots. We thought about it ourselves, but didnt design for it. Its a great defense for other robots trying to push us over. For those who suggest making a stronger drivetrain, think about the tons of teams that do not have their own drivetrains... think of all the teams that used the kit drivetrains because they dont have the uber mechanical Paul's or John's on their team... Not all of us can just design a great drivetrain... but make a triangle? now there is something we can do!

As Doug H mentioned earlier... we were "tipped" by team 302 in the last qualifying match in cleveland... we turned right around and selected that team as our alliance partner because they played very smart defense, and their design was innovative and worked well. Teams (including ours) were scared to go near ramp bots, because of the chance of tipping... so all they had to do was sit in the right spot in the field (not even moving!) and it would be a huge defensive strategy. I think the smarter move is to try to design a robot that can right itself... rather than eliminate the wedges.

So I will go back a few years, does anyone remember Clarkson's robot (http://www.team229.org/robot/11) in 2003? They were basically a drivetrain with two GIANT wings... that were "ramps" that folded down to block the ENTIRE HDPE surface. Now that was a cool and innovative design. Were they meant to aggressively tip other robots? No! Did other robots try to get on the ramp, drive up on their wings and flip over?? Yes! How cool!

I really hope that FIRST does not start making rules on what you cannot do with your robot design... it will limit the creativity, and we will all end up with a robot out of a box. Remember those lego toys where you got the kit and built the ship that looked like the one on the box? It was cool.. but your ship looked JUST like everyone elses... I hope I never see that day in FIRST.

[Ali Ahmed]

I completely agree. Look at 330, they had "ramps" on their robot and people were scared to go near them and see what happened. "Ramps" are just another design that teams come up with to play the game. If teams had ramps last year it would have been really awkward if you tried herd balls but it would work if you were trying to block the bar. Who knows, maybe next year the game will be such that having ramps would be very bad. You never know.

[dlavery]

i might be mixed up, but i thought it was rule T5 that allowed the tipping of other robots. i distinctly remember hearing/reading the posts of several rhode warriors that mention a decal on aquatread's flipper reading: "T5 is in effect".
If I remember correctly, there were actually three rules that had to do with tipping/flipping robots. One was <Rule F7>, and I believe you are correct that there was a <Rule T5>, and if I remember correctly there was also a <Rule J-something>. They all dealt with different aspects of how you could legally tip/flip robots. The <F7> rule sticks in my memory because as the controversy over robot-flipping started to heat up in 1998, there were teams that were wearing "No more F-7" buttons at the kick-off. I still have the rules manuals around somewhere. I will have to check when I get back home later this week.

Regarding Beth's comment, you got right at the center of the discussion that took place back then. Robots could be tipped over, and that was legal. Intentional damage or destruction of a robot was strictly prohibited. It was assumed that it was possible to tip over a robot without damaging it. But many teams raised the point that, given the very strict limitations on parts and robot construction abilities that were in place at the time, it was very difficult to build a robot that would be robust enough to handle being flipped over without taking some damage. And they were very upset with the idea that after six weeks of work to create their robot, that it could be severely damaged in just seconds by a simple little machine with a spring-powered spatula. It was an interesting debate, and one which started FIRST on the path toward the various restrictions on robot-on-robot contact that we have today.

-dave

[Dave Flowerday]

It was 1998 when FIRST added the rule against tipping devices.
I remember a few matches in 1995 where teams pushed each other off the side of the ramp - which not only caused the loser to tip over, but sometimes they'd actually tumble down the side of the ramp, rolling completely over a few times.

Here's a picture of the ramp in 1995, which incidentally appears to have a tipped over robot next to it. You can't see it well here, but the grey part of the ramp was actually raised up a bit from the red part by a few inches, so it didn't take much to get a robot to roll off the side.

http://web.archive.org/web/19991010060839/www.mv.com/org/usfirst/photo07.jpg

[Nitroxextreme]

i understand everyones ideas about the wedge type robot

but that is just part of the game

im not sure which robot it was but it was the one that had the wedges that flipped down and thats all they had
they were unable to hurt robots with higher ground clearance
if they had 4 wedges (which im not sure) they had 3 later

this may have been our doing when we drove over their robot without any effect on us

ps..sorry if we broke your wedge

[Lil' Lavery]

As intention flipping is no longer a part of the game, then we should take steps to minimize it. Right now, wedges seem to be the biggest cause of flipping, both intentional and non. I agree that more than 90% of flips are unintentional, but wedges increase the number of flips, and theres no way you can argue that.
Im not saying eliminate wedges as a whole, Im just saying enforce the flipping rules a bit more strictly and ask teams who's wedges become hazardous to do something about it. That could be as simple as adding stops to the wedges to prevent teams from driving too far up them.

[Dave Flowerday]

Im just saying enforce the flipping rules a bit more strictly and ask teams who's wedges become hazardous to do something about it.
That's fine, but then the same logic should be applied to any robot with a powerful drivetrain who successfully pushes over another team. I've seen plenty of robots without ramps but with plenty of muscle do this (unintentionally, probably, but the same can be said of the ramp-bots).
That could be as simple as adding stops to the wedges to prevent teams from driving too far up them.
If another team is driving up someone's ramps then the robot with ramps and tips then I don't see how it's the ramp-bot's fault. Anyone who is competing in this competition should know what happens to a robot's center of gravity when it drives up an incline ;)

[EricH]

As intention flipping is no longer a part of the game, then we should take steps to minimize it. Right now, wedges seem to be the biggest cause of flipping, both intentional and non. I agree that more than 90% of flips are unintentional, but wedges increase the number of flips, and theres no way you can argue that.
Im not saying eliminate wedges as a whole, Im just saying enforce the flipping rules a bit more strictly and ask teams who's wedges become hazardous to do something about it. That could be as simple as adding stops to the wedges to prevent teams from driving too far up them.

Very few tips are intentional. Even with the rules, some teams may decide to do it on the spur of the moment, and are promptly shut down, depriving their partners of a teammate. Regarding proportion of tippings: I saw more robots tip over due to entaglement high up, say in their arm (we were one of them, but we righted ourselves), or just plain having 9+ pounds too high up.

If the wedges are used properly, the flips are kept to a minimum. If someone has a drivetrain and a wedge and that's their robot, that could be and probably is improper use. If a team uses them for stabilization or defense against defenders, that is more likely to be a proper use.

If you add stops to the wedges to keep teams from driving too far up, how does that stop a team with, say, two tetras at the top of their arm from going partway up, tilting just enough to move their CG beyond a point of support, and falling down?

Expect that at least one and probably more robots will have some form of wedge, unless FIRST bans them. Implement a self-righting system if you have weight for it.

[Ianworld]

My teams bumpers were mentioned above. It was our teams alternative to what we considered disqualification magnent wedges.
http://stuypulse.no-ip.com/stuff/Yvette%20Magic%20Time.jpg


They were parallelograms spring loaded down. When a robot hit us they would dig into the cushioned side and push the bumpers up, pulling their front wheels off the ground and shifting some of their weight onto us. In theory they worked well but they had a couple issues. First was weight, to cover all 4 sides weighed about 12 pounds plus a 5 pound powered lifting mechanism which we removed. The other issue was that they just didn't work as well as wedges. We were rarely pushing other robots and while they didn't have the danger of tipping other robots we just didn't need that.

[Lil' Lavery]

If you add stops to the wedges to keep teams from driving too far up, how does that stop a team with, say, two tetras at the top of their arm from going partway up, tilting just enough to move their CG beyond a point of support, and falling down?
By adding the stops low down on the wedges. If you have the stop just high enough on the ramp that the front wheels lose contact with the floor, it will acheive the same thing as having no stops at all, but reduce the chance that it will tip. The stops couldnt possibly stop 100% of the tippings, but they would reduce them. There will never be a way that you can eliminate all tipping.

If another team is driving up someone's ramps then the robot with ramps and tips then I don't see how it's the ramp-bot's fault. Anyone who is competing in this competition should know what happens to a robot's center of gravity when it drives up an incline

Perhaps I should have worded that differently. What I meant was so that when a wedges gets under another robot, and the robot is travelling up it in some manner (either robot driving) it wont allow the robot to travel up the full incline of the ramp, therefore reducing the angle an which the robot is tilted, which reduces the chance its CG will extend beyond its supported area.


And beyond all that, most of claims to support wedges from a defensive point show them as a defense against "Bricks". Well, if its a brick it probably doesnt have an arm or a high CG, so if it tips, its definately not its own fault. The bots that do tip usually are ones with large arms or very high arms. Well if these bots are on a wedge, either the wedge is trying to force them out of position or a "brick" isnt the problem playing defence against the wedge. If its got a massive tetra carrying arm, its not a pure defensive bot, and if theres interaction between you and it, it is often the wedge bot trying to play last minute defense, not the armed bot. And in that situation it would most definately be the wedged bot's fault.

[EricH]

And beyond all that, most of claims to support wedges from a defensive point show them as a defense against "Bricks". Well, if its a brick it probably doesnt have an arm or a high CG, so if it tips, its definately not its own fault.
Is the "brick" attempting to block a robot that is attempting to cap? that capper is concentrating on capping, and if the "brick" drives up a wedge, particularly a side wedge, and falls over, how is that "not its own fault"?

Well if these bots are on a wedge, either the wedge is trying to force them out of position or a "brick" isnt the problem playing defence against the wedge. If its got a massive tetra carrying arm, its not a pure defensive bot, and if theres interaction between you and it, it is often the wedge bot trying to play last minute defense, not the armed bot. And in that situation it would most definately be the wedged bot's fault.

Most wedges are used for defense or stabilization. If it has a tetra-carrying arm, but is NOT using it, and has been playing defense the whole time, and it climbs up a wedge and gets stuck, whose fault is that?

Yes, the brickbot is not a problem if it is on a wedge --Match 70, Newton, was a good example-- but what if the wedge is on the SIDE of the wedgebot, and the wedgebot cannot move side to side, even under normal conditions? Whose fault is that if the brickbot tips over?

[Lil' Lavery]

Because of the "brick's" low CG, it should very very rarely tip unless something else forces it to do so.
If the armed bot is playing defense, fault would be assossiated depending on the situation.
Yes, the brickbot is not a problem if it is on a wedge --Match 70, Newton, was a good example-- but what if the wedge is on the SIDE of the wedgebot, and the wedgebot cannot move side to side, even under normal conditions? Whose fault is that if the brickbot tips over?
If the wedge can drive backwards, then in most (not quite all) situations its the wedges fault. Especially in an open field layout like this year. If the wedge can drive backwards, it can turn then avoid the "brick". If the brick keeps driving at you, eventually you'll hit a wall, and the brick will be called for pinning. If you dont have the time for a pinning situation, this year you could enter a loading zone, and if they follow you there, they will most likely be assessed the 30 pt penalty. In other years it would be different, but then again in other years tipping has been part of the game as well.
But if the wedge truly had NO OTHER option, it would be a refs call. If it had another option and it chose to tip the brick anyway, it would be the wedges fault. The brick was there to play defense, dont be upset when it does it sucessfully.

[EricH]

Because of the "brick's" low CG, it should very very rarely tip unless something else forces it to do so.
If the armed bot is playing defense, fault would be assossiated depending on the situation.

If the wedge can drive backwards, then in most (not quite all) situations its the wedges fault. Especially in an open field layout like this year. If the wedge can drive backwards, it can turn then avoid the "brick".

Did I say anything about the wedge bot moving BACKWARDS? Let us suppose (as one possible situation) that there are two brick bots defending the same wedge bot, which, for all intents and purposes, and for reasons unknown, only has side wedges. One brick bot gets behind it so it can't move backward (and we are supposing that this whole scenario takes less than 10 seconds) as the other charges from the side. The brick bot coming from the side hits the wedges hard enough to go up, hits the top, and falls over. Whose fault is that?

Brick bots should know enough to stay away from inclined planes that are not shallow enough to climb without tipping. Yes, a brick bot should have a low CG, and most, if not all, do. But if the slope that it is driving up is too steep for it, it will most likely fall over.

[Lil' Lavery]

Well that situation it wouldnt be the wedges fault. But that is one of the few situations I said it wouldnt be. Note how I said if it truly had no other option, it wouldnt always be the wedges fault.

[DarkJedi613]

I think you're all looking at this on too general of a level and with way, way, waaayyy too many "What if" situations. Obviously there are advantages and to disadvantages. FIRST can ban them, or they cannot. In the latter case teams should be aware that when driving a robot with it - they must be careful, teams going against a 'wedgebot' should know better than to drive themselves up it. Overall it must be handled in a case by case situation, no two situations in a FIRST match are going to be the same - the rules need to be written to guide the inspectors and referees who are the ones who must make the final decision.

[EricH]

Overall it must be handled in a case by case situation, no two situations in a FIRST match are going to be the same - the rules need to be written to guide the inspectors and referees who are the ones who must make the final decision.
Sample "guide" rule: If a robot drives up a wedge or other traction-reducing device and tips over, flips, or otherwise becomes inoperable, that is not the fault of the robot with said wedge. If, on the other hand, the robot with said wedge or traction-reducing device drives into the other robot, and the other robot becomes inoperable, that is (a penalty--FIRST's decision what) on the robot with the wedge. If both robots are judged at fault, that is a referee's call as to who gets penalized or not."

OK, it's a bit legalistic and all that, but it gets the point across (I hope) as to who is at fault in a general sense.

[Ctrl Alt Delete]

I don't think this should be against the rules. If the team has high angles on it's robot and it flips another robot, it gets a penalty. I don't think any teams intent is to play dirty. Ramps really are for only helping the team, not so much as a defense.