I have been scanning Youtube to see how the new game is playing out in the regionals when I stumbled upon this clip:
in this clip 3539 is herding the rolling goal before the end game buzzed. Is this Possession defined in the Q&A?
Possess / Possessing a Rolling Goal - Controlling the position and movement of a ROLLING GOAL. A ROLLING GOAL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the ROLLING GOAL remains in approximately the same position relative to the robot.
Since they did two 90 degree turns and the goal stayed in roughly the same position, I would have to say they should have earned a penalty for this.
Clearly, the Refs decided it wasn’t so in that match/regional it wasn’t. Have other regionals been run with such a loss definition of “possession”? Have others been run with a more “letter of the law” approach? Has this been clarified?
According to my understanding the new definition of possession is you have to be able to back off the goal without the goal following you… If it does then that is possession.
Spinning in place causes the goal to spin out of the robot because it moves so easily (most of the time at least), You have to learn how to drive a certain way with a goal inside your bot. If designed incorrectly it will be very difficult to do just about anything with it (legally).
I have seen a team in FL that swallows the goal as well however they were just a little bit to narrow so lining up was very difficult and when ever they actually did it they had to remain still on the field because sometimes they possessed it sometimes they didn’t.
3539 has been in at least one other event (a PA qualifier with one of the game designers in attendance) without being called for a “possession” violation, as far as I am aware. From the video, it seems that they keep the goal inside a “cave” in the robot, but the “cave door” is always open, at least until the end game.
The answer to your last sentence may depend on your definition of clarified, but the topic of goal possession has certainly been addressed in the official Q&A in the Game Definitions thread:
*[Answer] The ability to “posses” a Rolling Goal will not be something that the inspection process will test.
The referees will assess possession dynamically, on the field. The referees will be watching for situations that, in their opinion, represent control of all directions of motion of the Rolling Goal.
One way to understand is to visualize the following tests. If a robot can be pushed or pulled away from the Rolling Goal, while still in contact with the playing field surface, without causing the Rolling Goal to come away with the robot, the robot is not in possession of the Rolling Goal. Conversely, if the Rolling Goal can be pulled away similarly, without cause the robot to move/come away with the Rolling Goal, the Rolling Goal was not possessed.*
[Answer] [This] is the test that the referees will use when assessing possession …
i.e. is there a way to pull either the robot or the goal, without lifting either, that cause them to come away from each other freely.
[Answer] … if there is a way to visualize pulling away either the rolling goal or the robot, without lifting either, and have them come away from each other cleanly, the goal is not in the possession of the robot.
*[Question] Ruling #7 above uses the term “freely” and ruling #9 uses the term “cleanly” when describing how the robot and moving goal are pulled away. Can you confirm that so long as the robot and rolling goal can be pulled away from each other, with or without friction between them that the goal is not possessed?
As long as the robot grasping the Baton does not use it to pull/push the Rolling Goal and releases it to finish the scoring activity, the robot would not be in possession of the Rolling Goal…
*[Question] Does the “push” or “pull” mentioned in the above statement [in Post #5] have to be in a straight line? If not, can it include a dog leg or other sharp bend?
[Answer] It is not possible for us to rule on every possible form of possession. The test described in earlier posts is one method for assessing possession.
The final determination of possession will be made by the referees at the field, based on the situation at the time the call is made. *
*. . . Rolling Goal and Baton possession is clearly defined and will be interpreted appropriately by the referees. The Head Referee will be trained and certified for each of the competitions and will train his/her referees as well.
If the Rolling Goals or Batons are contained and controlled on all sides by a robot at any time they will be considered “possessed”. A robot that has the appearance of possessing the rolling goal will be watched closely by the referees, so please be careful in your designs… *
*The attached diagram of examples possession scenarios is a taken from the referee training materials and demonstrates the principals that apply to Rolling Goal possession. It is not an enumeration of all of the possible legal configurations.
Be aware, even if the Rolling Goal is only constrained on three sides, if there is excessive friction that holds/squeezes the Rolling Goal, the robot would still be in violation of the possession rule. *
*[Question] You say “if there is excessive friction.” What constitutes “excessive friction”? Would something that allows the goal to be pulled out, but doesn’t allow the goal to roll out freely be allowed?
[Answer]This will be a judgement call by the referee. In general, the Rolling Goal must roll out freely. Robot designs that may cause the Rolling Goal to bind, stick, become wedged, trapped, etc. risk violating the possession rule and should be avoided.*
*[Question] Ruling #7, #9, and #15 affirm that the pull test is the primary method of determining goal possession. For clarity, is the pull test still satisfied when the rolling goal freely separates from the robot by changing directions two times? Keep in mind that in this situation the rolling goal is still removed cleanly without moving the robot. Ex. The rolling goal is constrained on three sides and the fourth side has a tab with a remaining opening larger than the rolling goal such that it rolls out freely.
A: No, this is not allowed. The robot or rolling goal must be pulled on a single vector. The fourth side tab should fail inspection.*
Based on these answers from the official forum, I would say that the Game Manual version of the definition of possession is gone, and the pull test is in its place. Teams relying on the Game Manual alone will likely be suprised by what is allowed. Post 17 is overruled by 26 (to avoid possession, the goal must be able to roll out in a straight line). The one issue that still seems unclear is whether or not the inspection process will include an assessment of the legality of goal managing mechanisms under the possession rule.
I happened to see that in FLL this year, the official Q&A was replaced with a short list of “official rulings”. I am not sure how often the list was edited, but as of a few weeks ago it was short and relatively easy to read and understand in comparison to the typical official Q&A.
I hope this will become the practice in FTC also.
As it is now, by late in the season, you have to read the entire Game Manual, then read the entire official forum (maybe a couple hundred official forum posts), then study the and interpret the relationships between the various statements in order to arrive at a good understanding of the game. Makes it tough to actually “know the rules” as Ken urges in his recent blog post http://firsttechchallenge.blogspot.com/2010/11/knowing-rules.html.
A short repeatedly updated list of official rulings, with version numbering and dating for each update, would be really nice.
I find it a bit irksome that this “separation” rule has come about after we have designed our robot. It seems that they have changed a scoring/penalty rule substantially. For my team, this is going to change our entire approach to the game. What’s interesting is that the old definition and the new definition are both on the official Q&A in two different threads making finding the new updated rules harder to find.
Sadly, this makes batons that less important and the see-saw that much more necessary. This will make the game more one dimensional with more teams lining up for the ramps well before the end game. Oh well, we’ll do the best we can in this changing game environment.
The orginal rules for handling the goals outside of the end game were hard to interpret, so they made rule revisions including a definition of “possession” and put them out in revision 2 of the game manual–and splashed the new “possession” definition across all of the the Q&A threads so that everyone would be sure to know the manual was revised.
That revision 2 definition of “possession” is the definition in the official forum post you linked–what you call the old definition–and is still the definition in the manual–so it is not old, in that sense.
The “new definition” or the “pull test” evolved only in the game definitions thread in response to teams’ questions on the “possession” definition. The pull test is the only easily understood or practical version of the possession definition given to date, but it is different than what many teams will think from reading the possession definition alone.
I agree because what will you do besides defense in the driver control period then in the end game you can get a max of 40 points (most likely 30 because it will be very hard to get both robots and both goals on the one seesaw).
Yes I thought so too, at the beginning. The Get Over It game now looks something like Quad Qunadary but with dispensers, like Face Off. I was surprised when the answers in the official forum were given allowing three-sided containment of the goals.
Man, did we have trouble with this one. At most of the events we’ve been to so far, the referees told us that our robot doesn’t meet the official definition requirements, which has led to a lot of discussion about the forum posts. I think that the forum has made their intentions clear as to what a robot should look like, but both we and the refs weren’t sure whether the pull test overrules the definition. This has proven to be a problem for us, because we pass the pull test but don’t quite fit the definition.
Concerning the game’s similarity to Quad Quandary, I say it’s okay. There’s still the possibility of stealing the goals or putting them in the corners to make them inaccessible. The good thing is that everybody can have a goal; there’s not going to be one robot doing all the work while their alliance partner sits and twiddles their thumbs. I also think that batons will play a big role in state and world championships. At scrimmages, most people won’t have effective dispensing or scoring mechanisms. The matches will get much more exciting as the season progresses and the robots have the potential for more points.
The problem with the definition and forum posts may be more obvious for your robot than for others, but the problem is there for any robot, because the problem is in the definitions, not the robots.
The definition in section 2.3 of the manual goes like this:
Possess / Possessing a Rolling Goal- Controlling the position and movement of a ROLLING GOAL. A ROLLING GOAL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the ROLLING GOAL remains in approximately the same position relative to the robot.
The short version of this definition apparently is that “possession” is “controlling the position and movement of a ROLLING GOAL.” Every robot capable of controlled movement is capable of possession by that standard, such as in the case of a short, straight-line push of the goal.
The longer version says that the goal is considered possessed if the goal remains in approximately the same position relative to the robot as the robot moves OR changes orientation (with backing up and spinning given as examples of moving and of changing orientation, respectively). If you read this literally, all you need is one linear move, such as a short, straight-line push, OR one spin, where the goal remains in approximately the same position relative to the robot, and you are possessing the goal during that move.
This is pretty obviously not what was intended, even without the forum posts, moreover, the pull test in the forum responses cannot be harmonized with any literal reading of these definitions from the manual.
Ideally, the manual would be revised to reflect the forum posts, rather than be left as-is, to mislead teams and officials alike.
I suppose the problem is that the definition is a lot more vague than the pull test and can be interpreted many different ways. I think the purpose of the definition was to say, “the robot cannot constrain the goal’s movement to the movement of the robot, i.e. the robot cannot enclose the goal.” But that came across a little differently. The GDC is handling it fairly well, but I think that maybe a little more organization on the forums would help teams, as you guys said earlier.
You may be right that the pull test (a functional test for grasping and/or enclosure) was the intent or purpose of the definition all along, and I know the GDC has nothing but good intentions–there is zero intent to mislead.
But confusion and misleading is the result of the current definition. There would not be so many questions on the point in the forum otherwise. People trying to understand the definition are asking questions in the forum, or are reading the answers. People who read the definition alone and think they understand (or who miss the “definitions” thread in the forum) are misled.
Under the circumstances, the definition would ideally be updated, rather than just interpreted in the forum. Alternatively, an official rulings list would be useful, one that lets teams (and officials, who often have one reading to get it right) get the needed information without reading many posts, sometimes conflicting. (Compare 27 to 17, and 27 to 5, for example.)
Or maybe they should just put the pull test in the game manual along with the definition. It might help a little to make sure people know it’s official.
A list of ruling examples, like you said, would be great, or maybe teams could have the ability to discuss designs that you’re unsure about with your state’s head ref; by now, they know what’s going on and can give official rulings.
In looking through the game manual, I don’t actually see any rule that prevents the possession of the rolling goal. The only rule I see is <SG8> which prevents the “lifting, grasping or holding” of the rolling goals.
Q1. Is lifting, grasping or holding the same as possession?
Q2. Did I just miss the correct rule which prevents possession?
Which says, in effect, that “lifting, grasping or holding” = “possession”, or at least that “possession” is prohibited by <SG8>.
(This might be another example where actually updating the rule, or making a list of official rulings, would help, instead of relying on everyone catching every forum post.)
Update: a new post in the official forum has added the word “possessing” to the list of prohibited actions in <SG8>
Just wanted to add:
I think the forums address the topics in question rather well, it just seems that it could be a hassle for teams to read through all of the posts. The referees at the qualifiers we’ve been to recently were clear on the rules and were willing to answer quick questions about them. Despite any confusion, teams will be able to get the rules from both the Q&A forum and the refs.
Does anyone know the exact outside diameter if the “four-Inch” PVC scoring tubes for the rolling goal? There seem to be two possible types of PVC that are called “four-inch”. One is used for drain pipe and has a thinner wall, and the other is the heavier walled Schedule 40 pipe. The field build manual indicates that the caps which are screw-mounted onto the base of the rolling goal are the light weight, thinn-walled FLAT-ENDED DRAIN PIPE style of caps, but these do not accept the larger Sch 40 pipe. So we either have the wrong caps or the wrong pipe. Anyone know which is the right pipe and the correct OD?
