2nd Most Awaited Q and A Answer?

[Tuba4]

The following has been posted to the Q & A system:

In a prior answer it was stated that an appendage can fork outside the frame perimeter yielding a Y shaped appendage. Can an appendage be attached to the frame at 2 points and terminate in 2 points as long as they are joined by a cross member, yielding an H shaped appendage?

[RRLedford]

Originally Posted by Tuba4

The following has been posted to the Q & A system:

In a prior answer it was stated that an appendage can fork outside the frame perimeter yielding a Y shaped appendage. Can an appendage be attached to the frame at 2 points and terminate in 2 points as long as they are joined by a cross member, yielding an H shaped appendage?

Why do we need a bar to make the H - shape? The robot it self is the cross bar of the H, at least as far as the contiguity test goes, that could pass.
If the robot itself CAN'T be the H-bar, then where beyond the two pivot points must the H-bar fall? Must it swing out past the perimeter to make it a legal forked arm? What if the deploy fails in the muddle and the H-bar stays inside the robot perimeter while the two tops of the H break the perimeter? Is this a double appendage deploy or can we trace contiguity back inside the perimeter and around between the two sides of the H?

We really need some better clarification on the same level as the way the bumper mounts are detailed with good example diagrams.

-RRLedford

[Jon Stratis]

RRLedford -

We really don't want the entire rule book to go the way of the bumpers - aka super detailed. Take a look at last year's Inspection Checklist - 1/6 of the entire checklist was about the bumpers! If we do that for everything, Inspections will take hours to go though.

The definition of contiguous really isn't that difficult to understand in this scenario. Anyone saying the entire robot makes any number of appendages "contiguous" is lawyering (or engineering...) the rules. That's just ridiculous. Your robot isn't the appendage.

As for your suggestion of a frame that extends in all directions... that would be against many rules. First, your frame must be fixed and non-articulated (R01-2). So your "frame" that extends in all directions at once would be extending past all edges of the frame perimeter, not just one (G21).

The clear intent of the rules would prohibit extending anything through a corner, as that would pass it through two sides of the frame perimeter. Projecting on a diagonal near the corner, however, is a little less clear in the rules... however as the Q&A emphasizes "single edge" in answering a similar question, I don't think that's legal.


TLDR: Use some common sense and stop trying to lawyer (or engineer) the rules to your advantage. The inspectors and refs will call you on it.

[RRLedford]

Originally Posted by Jon Stratis

RRLedford -

We really don't want the entire rule book to go the way of the bumpers - aka super detailed. Take a look at last year's Inspection Checklist - 1/6 of the entire checklist was about the bumpers! If we do that for everything, Inspections will take hours to go though.
Lacking more rigorous and concise language than has so far been offered on the appendage confusion, I don't see how we can finalize our designs.

The definition of contiguous really isn't that difficult to understand in this scenario. Anyone saying the entire robot makes any number of appendages "contiguous" is lawyering (or engineering...) the rules. That's just ridiculous. Your robot isn't the appendage.
Well than tell please tell me what is it that can make anything about your robot become DIS-CONTINUOUS?

As for your suggestion of a frame that extends in all directions... that would be against many rules. First, your frame must be fixed and non-articulated (R01-2). So your "frame" that extends in all directions at once would be extending past all edges of the frame perimeter, not just one (G21).
As I stated, ONLY our frame ABOVE the bumpers would expand. The frame at bumper level would stay fixed where it was. As long as the expanding elements maintained contiguity with each other, this should be legal.

The clear intent of the rules would prohibit extending anything through a corner, as that would pass it through two sides of the frame perimeter. Projecting on a diagonal near the corner, however, is a little less clear in the rules... however as the Q&A emphasizes "single edge" in answering a similar question, I don't think that's legal.

Well if NEITHER single edge would be extended beyond the 14" limit, then which edge would the violation be related to? This example clearly points out the how the rules often overlook things like WHERE THE EDGES INTERSECT, Buckminster Fuller would not appreciate the FIRST Game Rules
as far as how they assume everyone must engineer things in a rectilinear fashion. Some of us think & design diagonally and triangularly.

TLDR: Use some common sense and stop trying to lawyer (or engineer) the rules to your advantage. The inspectors and refs will call you on it.

My common sense is being short circuited by the very weak language surrounding the "appendage" definition, and this problem has lasted much too long.

-RRLedford

[Tuba4]

Originally Posted by RRLedford

Why do we need a bar to make the H - shape? The robot it self is the cross bar of the H, at least as far as the contiguity test goes, that could pass.

Absent some type of connecting linkage, the two arms would be separate, independently operating appendages. A linkage would force them to operate as one and be in compliance with rule R02. Hopefully.

[RRLedford]

Originally Posted by Tuba4

Absent some type of connecting linkage, the two arms would be separate, independently operating appendages. A linkage would force them to operate as one and be in compliance with rule R02. Hopefully.

So, you are assuming that as long as some "connecting linkage," that establishes contiguity between the two protruding arms of the appendage, passes outward, along with the arms, and fully beyond the perimeter, as part of the same motion that extends the arms outward., then this makes them effectively a single appendage.

This implies you are also assuming that two arms joined at their base to a single hinge plate fixed onto the frame, which plate remains permanently inside the frame perimeter, and by which this hinge plate swinging, would both arms be actuated to move IN UNISON beyond the frame periphery, that such a mechanism would be considered TWO appendages, because the the element that establishes their "connecting linkage" (for contiguity) never travels outward along with the arms beyond the frame perimeter.

So if both these assumptions are valid, then the conclusion would be that as long as the appendage's "arms" have a "connecting linkage" which travels along with the motion of these MULTIPLE "arms," which ALL break the frame perimeter, so long as that connecting linkage also breaks the frame perimeter, this connected group of appendage "arms" will be considered to be a SINGLE appendage.

This would make the critical test be whether or not the "connecting linkage" element fully tracks along with the motion of the "arms" and ends up always traveling through the space near the robot such that, along with the arms, it ALSO always breaks the plane of the edge perimeter whenever those "arms" extend beyond the frame perimeter.

-RRLedford

[Tuba4]

Originally Posted by RRLedford

So, you are assuming that as long as some "connecting linkage," that establishes contiguity between the two protruding arms of the appendage, passes outward, along with the arms, and fully beyond the perimeter, as part of the same motion that extends the arms outward., then this makes them effectively a single appendage.

This implies you are also assuming that two arms joined at their base to a single hinge plate fixed onto the frame, which plate remains permanently inside the frame perimeter, and by which this hinge plate swinging, would both arms be actuated to move IN UNISON beyond the frame periphery, that such a mechanism would be considered TWO appendages, because the the element that establishes their "connecting linkage" (for contiguity) never travels outward along with the arms beyond the frame perimeter.

So if both these assumptions are valid, then the conclusion would be that as long as the appendage's "arms" have a "connecting linkage" which travels along with the motion of these MULTIPLE "arms," which ALL break the frame perimeter, so long as that connecting linkage also breaks the frame perimeter, this connected group of appendage "arms" will be considered to be a SINGLE appendage.

This would make the critical test be whether or not the "connecting linkage" element fully tracks along with the motion of the "arms" and ends up always traveling through the space near the robot such that, along with the arms, it ALSO always breaks the plane of the edge perimeter whenever those "arms" extend beyond the frame perimeter.

-RRLedford

Actually....no. The test is much simpler. If two appendages which operate independently are connected by some type of linkage so they can no longer operate independently but only operate in unison, they are a legal appendage. That is what I am going for in my submission to the Q&A.

[RRLedford]

Originally Posted by Tuba4

Actually....no. The test is much simpler. If two appendages which operate independently are connected by some type of linkage so they can no longer operate independently but only operate in unison, they are a legal appendage. That is what I am going for in my submission to the Q&A.

Well, when you say "only operate in unison," is that restricted to only their movement for deployment extension beyond the frame perimeter, but after deployment motion completes, can they can perform independent functions for each arm? Or, must they continue to operate in unison performing a single function by their coordinated movements, for as long as they remain outside the frame perimeter?

What if my bridge tilt arm is forked and one side of fork can also grab a ball and return it into the robot. Sometimes it would extend to tilt the bridge, and sometimes it would extend to get a ball. Would this be a violation, even though both arms of the appendage extend outward and return inward "in unison" as you describe?

-RRLedford

[Tuba4]

Originally Posted by Tuba4

In a prior answer it was stated that an appendage can fork outside the frame perimeter yielding a Y shaped appendage. Can an appendage be attached to the frame at 2 points and terminate in 2 points as long as they are joined by a cross member, yielding an H shaped appendage?

This question was just answered in the Q & A system.

"Yes but the contiguous part of the appendage must be outside the Frame Perimeter"

[MrForbes]

The conservative approach wins again....

[johnr]

...... and light saber test. I read this thread and still not sure about something. If you drew a tic-tac-toe game with center box being the robot and the center squares along the edges being were your app comes out, can the app enter into the corner boxes?

[Tuba4]

And here is another recent question and new answer which impacts our discussion here:

Q. Will you please either clarify the ‘appendage’ definition, or state the legality of an appendage design with two separate arms that extend beyond a single frame perimeter edge and driven by a single/common mechanism inside the frame perimeter? The related Q&A responses seem rather ambiguous. Thanks.

A. As the other responses indicate, there is no formal definition of "appendage". However, one appendage (as allowed in Rule [G21]) would be one contiguous assembly. The contiguous part of the appendage must be outside the Frame Perimeter.

[Dale]

This would seem to rule illegal all of the ball collection systems teams are making involving cylinders and discs with surgical tubing attached unless all of those pieces of tubing remain inside the framer perimeter at all times as the cylinder spins. Doesn't impact us but it will effect a lot of teams.

[Siri]

Originally Posted by Dale

This would seem to rule illegal all of the ball collection systems teams are making involving cylinders and discs with surgical tubing attached unless all of those pieces of tubing remain inside the framer perimeter at all times as the cylinder spins. Doesn't impact us but it will effect a lot of teams.

Unless the central pipe or part thereof also lies outside the frame perimeter. Right?

[Dale]

As that pipe moves out of the frame perimeter there's going to be a period of time where you have more than one appendage for a fraction of a second. Unless the GDC makes another ruling that would seem to be a violation. I suppose you could build one that only has tubing on one side and a way to stop it with that tubing facing inwards to park but it wouldn't be fun.