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aldaeron 10-01-2010 16:25

Carrying <G44>
 
1 Attachment(s)
I am new to FIRST and wanted to get everyone's opinion on Carrying (Rule G44). I was wondering if you intentionally kick the ball on top of your robot - (i.e. using your robot as a ramp - see attached image) would it count as CARRYING when the ball left the floor?

Please note: I am aware that the attached image violates rule R16

Thanks!

-matto-

GaryVoshol 10-01-2010 16:31

Re: Carrying <G44>
 
I would think that would be CARRYING. For the half-second while the ball was going up your robot ramp, if your robot makes a sharp turn, the trajectory of the ball would change. Thus your robot's motion was controlling the movement of the ball, the defintion of POSSESSION. POSSESSION with the ball not in contact with the floor is CARRYING.

SteveGPage 10-01-2010 16:40

Re: Carrying <G44>
 
Quote:

Originally Posted by aldaeron (Post 895854)
I am new to FIRST and wanted to get everyone's opinion on Carrying (Rule G44). I was wondering if you intentionally kick the ball on top of your robot - (i.e. using your robot as a ramp - see attached image) would it count as CARRYING when the ball left the floor?

Please note: I am aware that the attached image violates rule R16

Thanks!

-matto-

In addition to what Gary said:
1) You have the 5" wide bumpers to contend with first, so the idea of a wedge shape for shooting wouldn't be possible <R07-D>
2) If you then tried to get it up over the bumpers, you now also have the issue of <G30>

Hope this helps!

Welcome to FIRST!

Best regards,

Steve

kirtar 10-01-2010 16:41

Re: Carrying <G44>
 
It depends, but I'm inclined to say it's not. If your robot was to turn, while the trajectory would change. It may not remain in the same location relative to the robot because it is probable that it will slip and/or roll and stay in roughly the same position that it was (absolute position). Its kind of like pulling a tablecloth from under a bunch of glasses. In addition, if you were to back up, the relative position would quite obviously change. I'd say this one would need to go on Q&A, although I'm not seeing a way to do this well because of the whole bumpers thing.

The reasoning used would also imply that in the instant that a ball lands on your robot off of a short fall such that it rolls off of your robot that it will be counted as carried. In other words, as long as the drop is short, it implies that you carry the ball for an instant in time whenever a ball for example, rolls of the platform and onto your robot regardless of a design to make it fall off.

Creator Mat 10-01-2010 17:25

Re: Carrying <G44>
 
i understand the game manual is overrides the the game video but in the video they made a point to say even accidental carrying is illegal. Also from what i saw in the game manual they made no provisions saying accidental carrying is allowed. So i think this idea of having an "accidental" carrying method would be illegal.

BrendanB 10-01-2010 17:53

Re: Carrying <G44>
 
What I read in the manual is that if your robot has a ball on top of it whether intentional or not, it will be deemed a penalty. They also made a mention of recommending that teams build their robots so that no balls could wind up sitting on top of your robot. If a ball is moving on top of your robot, I would like to think that it is not a penalty in that a penalty only comes when a ball is at rest on your robot, but I would check in FIRST QandA just to check.

AmoryG 10-01-2010 18:30

Re: Carrying <G44>
 
If it's touching the playing field then you're not carrying the ball. It looks like in the picture part of the ball is touching the ground. It does not violate <G44>.

hipsterjr 10-01-2010 21:20

Re: Carrying <G44>
 
Question:

Would a funnel designed to catch returned balls so that they land right in front of your kicker be in violation of the <G44>? You aren't carrying the ball, just "influencing" its trajectory

Pausert 10-01-2010 21:28

Re: Carrying <G44>
 
Oh, I want to know that too...

Quote:

Originally Posted by AmoryG (Post 895949)
If it's touching the playing field then you're not carrying the ball. It looks like in the picture part of the ball is touching the ground. It does not violate <G44>.

Except the picture and OP indicate that the team would be using their robot as a ramp for the ball, which seems to me as if it would constitute CARRYING. It definitely seems to be a use of the robot to influence (control) the balls flight.

See:

Quote:

Originally Posted by Rules
CARRYING: POSSESSING a BALL that is not in contact with the FIELD.

POSSESSION: Controlling the position and movement of a BALL. A BALL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the BALL remains in approximately the same position relative to the ROBOT.


Chris is me 10-01-2010 21:30

Re: Carrying <G44>
 
Quote:

Originally Posted by hipsterjr (Post 896130)
Question:

Would a funnel designed to catch returned balls so that they land right in front of your kicker be in violation of the <G44>? You aren't carrying the ball, just "influencing" its trajectory

I'd ask the Q&A. My opinion? If you turn or back up as it falls down the chute, does the ball stay in the robot? if so, it's CARRYING

hipsterjr 10-01-2010 21:34

Re: Carrying <G44>
 
Quote:

Originally Posted by Chris is me (Post 896142)
I'd ask the Q&A. My opinion? If you turn or back up as it falls down the chute, does the ball stay in the robot? if so, it's CARRYING

It would fall right off the robot and not be in contact with the robot for more than a second. The funnel idea would just keep it from bouncing off the robot and flying across the field and make us chase it down.

Donut 10-01-2010 22:31

Re: Carrying <G44>
 
Quote:

Originally Posted by hipsterjr (Post 896130)
Question:

Would a funnel designed to catch returned balls so that they land right in front of your kicker be in violation of the <G44>? You aren't carrying the ball, just "influencing" its trajectory

Remember that your robot must be entirely surrounded by bumpers, and since you cannot extend beyond the starting frame (ignoring last 20 seconds and tower touching...) any guides would lead the ball to simply hit your bumper and bounce away.

Any funnels that guided the ball on the inside of the bumpers would cause the ball to violate the 3" incursion rule beneath the robot (you could also get potentially flagged for interacting with game pieces above the bumper zone).

So I'd say you will end up with a penalty of some sort for this device, which one I don't know.

hipsterjr 10-01-2010 22:43

Re: Carrying <G44>
 
OK, let me word it this way...

All robots are encouraged to have some kind of slope so that balls don't get stuck or ride on top of the robot. All I am talking about is adding a sort of "tunnel" like cover to the slope that would make it like a tilted funnel. This would cause the ball to roll in front of us instead of bouncing away


excuse the quick rough drawing

aldaeron 10-01-2010 23:07

Re: Carrying <G44>
 
I just wanted to clarify my original question. Again, I am aware the picture above is illegal with respect to bumpers and many other things. It's just meant to be a simple illustration.

What I am trying to figure out is - for the fraction a second that the ball is touching the robot and not touching the floor - is that a carry?

I think this will need to be answered by FIRST, but do appreciate all the responses.

I agree that robots will need some sort of covering (pyramid, dome, etc) to ensure balls bounce off the robot and can't be stuck.

Donut 10-01-2010 23:28

Re: Carrying <G44>
 
Some manual definitions:

Quote:

POSSESSION: Controlling the position and movement of a BALL. A BALL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the BALL remains in approximately the same position relative to the ROBOT.
Quote:

CARRYING: POSSESSING a BALL that is not in contact with the FIELD.
According to this, a ball that merely bounces off the top of a robot is not considered POSSESSED. However a ball that would then pass through some sort of "funnel" would be considered POSSESSED while inside the funnel, and thus would incur a <G44> penalty. Any air herding device, regardless of whether it is within the bumper zone or at the edge of the robot, would cause a ball to be POSSESSED while in the air resulting in CARRYING.

With these definitions balls can bounce off of robots without penalties, so as long as you do not use something considered a MECHANISM you can strategically deflect balls (no funneling) with your robot as they fall from the ball return.

Chris is me 11-01-2010 00:35

Re: Carrying <G44>
 
Can you draw a picture of where the ball lands?

If I'm thinkning what I think it is and it's basically just a flat slope with nothing else on it (ie if you turn it slides off, if you go backward it slides off) then I think it's legal (Q&A prevails of course)

lcoreyl 11-01-2010 22:07

Re: Carrying <G44>
 
It appears the possible loophole here is:
______________
POSSESSION: Controlling the position and movement of a BALL. A BALL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the BALL remains in approximately the same position relative to the ROBOT.

CARRYING: POSSESSING a BALL that is not in contact with the FIELD

<R19> ROBOTS must be designed so that in normal operation BALLS cannot extend more than 3 inches inside the FRAME PERIMETER below the level of the BUMPER ZONE.
______________

According to the definition, possession only happens if you move. Carrying includes the definition of possession, so if you're not moving, you're not in possession, you're not carrying. So your funnel would seem to work if you don't move during the period it is being funneled and you kick it from above the bumper zone

However, since they are playing off of a soccer analogy, I'm pretty sure they are intending for you to never do anything with the ball other than have it deflect off the top. Otherwise you could build a shooter that doesn't move.

StephLee 12-01-2010 09:16

Re: Carrying <G44>
 
Quote:

Originally Posted by lcoreyl (Post 897040)
It appears the possible loophole here is:
______________
POSSESSION: Controlling the position and movement of a BALL. A BALL shall be considered in POSSESSION if, as the ROBOT moves or changes orientation (e.g. backs up or spins in place), the BALL remains in approximately the same position relative to the ROBOT.

CARRYING: POSSESSING a BALL that is not in contact with the FIELD

<R19> ROBOTS must be designed so that in normal operation BALLS cannot extend more than 3 inches inside the FRAME PERIMETER below the level of the BUMPER ZONE.
______________

According to the definition, possession only happens if you move. Carrying includes the definition of possession, so if you're not moving, you're not in possession, you're not carrying. So your funnel would seem to work if you don't move during the period it is being funneled and you kick it from above the bumper zone

However, since they are playing off of a soccer analogy, I'm pretty sure they are intending for you to never do anything with the ball other than have it deflect off the top. Otherwise you could build a shooter that doesn't move.

I could be wrong, but I read the definition of possession slightly differently. I thought it meant that a ball is considered possessed if it would maintain approximately the same location relative to the robot IF your robot moved. For example, if I have a grip on it and don't move, it's still being possessed because it would satisfy the criteria if I DID move.

That's for the Q&A to decide, but that's how I read the rule.

Matt C 12-01-2010 09:34

Re: Carrying <G44>
 
Remember the NEXT RULE in the manual is <G45>

Quote:

<G45> Active BALL control - ROBOTS may not control BALL direction with active MECHANISMS above the BUMPER ZONE. Violation: PENALTY.

hipsterjr 12-01-2010 09:46

Re: Carrying <G44>
 
Quote:

Originally Posted by Matt C (Post 897336)
Remember the NEXT RULE in the manual is <G45>

That is the source of the debate. Is a chute concidered "active"? We'll find out tomorrow.

jvriezen 12-01-2010 10:26

Re: Carrying <G44>
 
Seems like an upper surface on your robot made of memory foam to reduce bouncing, contoured and sloped such that balls hitting the foam will tend to land in front of the robot would be a good idea.

Since the robot is encouraged to be designed to not unintentionally carry balls, you have to have some sort of sloping top, might as well make it slope in your favor, and construct it of material in your favor.

Or is this going to violate the rules?

kirtar 12-01-2010 14:38

Re: Carrying <G44>
 
Quote:

Originally Posted by jvriezen (Post 897367)
Seems like an upper surface on your robot made of memory foam to reduce bouncing, contoured and sloped such that balls hitting the foam will tend to land in front of the robot would be a good idea.

Since the robot is encouraged to be designed to not unintentionally carry balls, you have to have some sort of sloping top, might as well make it slope in your favor, and construct it of material in your favor.

Or is this going to violate the rules?

How I'm thinking about it I doubt it will break the rules, but that depends on implementation. If you put some kind of siding on it that would cause the relative position to not change while you turn then you should be fine. Any changes in velocity of your robot are unlikely to have a significant impact on the absolute velocity/position of the ball, causing a definite change in relative position. The only thing that I'm concerned about is what you mean by contoured. If you mean putting a track to direct the ball, I think that's a little questionable.

Kims Robot 12-01-2010 15:01

Re: Carrying <G44>
 
1 Attachment(s)
I had the same idea, although I was thinking of making it out of something slick just so the ball couldnt get caught (I like the dampening of the memory foam but I would be concerned about it potentially possessing the ball)

Here is my fairly crude drawing, but it should get the point across :)

Other than making some sort of pyramid or convex surface Im not sure how else you prevent yourself from possessing a ball...

(Remember if you do ask this in the Q&A dont use a specific robot design, just refer to the rules and ask questions about the rules themselves).

jvriezen 12-01-2010 15:10

Re: Carrying <G44>
 
Quote:

Originally Posted by kirtar (Post 897534)
How I'm thinking about it I doubt it will break the rules, but that depends on implementation. If you put some kind of siding on it that would cause the relative position to not change while you turn then you should be fine. Any changes in velocity of your robot are unlikely to have a significant impact on the absolute velocity/position of the ball, causing a definite change in relative position. The only thing that I'm concerned about is what you mean by contoured. If you mean putting a track to direct the ball, I think that's a little questionable.

By contoured, I was envisioning something like a playground slide, perhaps with some plexiglass walls that increased the catching area. I would like to think that as long as you have a non-moving top side that 'sheds' the balls (via gravity) off of the robot to avoid carrying them, it shouldn't really matter what the shape and material of that shedding surface is.

But I'll agree, it is definitely something I wouldn't recommend doing until cleared by FIRST.

jvriezen 12-01-2010 15:17

Re: Carrying <G44>
 
Quote:

Originally Posted by Kims Robot (Post 897551)
I had the same idea, although I was thinking of making it out of something slick just so the ball couldnt get caught (I like the dampening of the memory foam but I would be concerned about it potentially possessing the ball)

Here is my fairly crude drawing, but it should get the point across :)

Other than making some sort of pyramid or convex surface Im not sure how else you prevent yourself from possessing a ball...

(Remember if you do ask this in the Q&A dont use a specific robot design, just refer to the rules and ask questions about the rules themselves).

Your diagrams are very much like my original thinking. But a slick surface will just have them bounce off most of the time.

Bob Steele 12-01-2010 15:48

Re: Carrying <G44>
 
In my opinion if you have something on top of your robot that could potentially carry the ball ( IE something with sides on it....) it will be considered illegal.

therefore if you decide on some type of chute system that IF your robot were turning when a ball is engaged by it and IF the chute would make the ball turn in the direction you are turning you would have an illegal mechanism.

A simple slanted flat surface would seem to be ok given this approach.

A u-shaped track or a flat surface with sides to guide the ball would not


by the way
I do really like the idea of referring to the balls as "possessed :eek: "
Puts a whole different "dark" light on the game....;)

Good Luck and we will see you at the competition..!!

jvriezen 13-01-2010 09:24

Re: Carrying <G44>
 
Quote:

Originally Posted by Bob Steele (Post 897575)
In my opinion if you have something on top of your robot that could potentially carry the ball ( IE something with sides on it....) it will be considered illegal.

therefore if you decide on some type of chute system that IF your robot were turning when a ball is engaged by it and IF the chute would make the ball turn in the direction you are turning you would have an illegal mechanism.

A simple slanted flat surface would seem to be ok given this approach.

A u-shaped track or a flat surface with sides to guide the ball would not

POSSESSION requires that the ball stays in the same position relative to the robot as it turns or reverses. Since a chute/track is inclined, the ball will be rolling down the ramp-- although the ramp influences the ball's position as you turn, it doesn't stay still relative to the robot, and it isn't active, so I think it is legal, but of course Q & A has the final say.


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