Team Update #6

[Jon236]

Section 8 – The Robot, Rev F has been updated to include the following edits:
FRAME PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS attached) that are within the BUMPER ZONE. To determine the FRAME PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon. Note: to permit a simplified definition of the FRAME PERIMETER and encourage a tight, robust connection between the BUMPERS and the FRAME PERIMETER, minor protrusions such as bolt heads, fastener ends, rivets, etc are excluded from the determination of the FRAME PERIMETER.

[EricH]

And if you're wondering why no link was included, Jon just quoted the entire update.

Simple update, making life just as simple.

Or not... Better get those lower frames a little bit smaller if bolt heads sticking outside the frame perimeter will cause rules violations...

[Bryan Herbst]

Originally Posted by EricH

And if you're wondering why no link was included, Jon just quoted the entire update.

Simple update, making life just as simple.

Or not... Better get those lower frames a little bit smaller if bolt heads sticking outside the frame perimeter will cause rules violations...

The update specifically states that "minor protrusions such as bolt heads, fastener ends, rivets, etc are excluded from the determination of the FRAME PERIMETER."

Thus it is now easier to built a nice, sturdy bumper!

[EricH]

Originally Posted by Tanis

The update specifically states that "minor protrusions such as bolt heads, fastener ends, rivets, etc are excluded from the determination of the FRAME PERIMETER."

Thus it is now easier to built a nice, sturdy bumper!

Doesn't do anything for determining violations of the frame perimeter by bolts in the lower frame areas. What they're saying is that you can have bolts in the bumper zone, and they won't count as part of the frame perimeter (and presumably, won't count as a violation). What they aren't saying is whether or not this applies below (and above) the frame perimeter.

[Chris is me]

Originally Posted by EricH

Doesn't do anything for determining violations of the frame perimeter by bolts in the lower frame areas. What they're saying is that you can have bolts in the bumper zone, and they won't count as part of the frame perimeter (and presumably, won't count as a violation). What they aren't saying is whether or not this applies below (and above) the frame perimeter.

Where does it say that? It just says that bolts sticking slightly out of the FRAME PERIMETER are fine, doesnt say these bolts have to be on the BUMPER PERIMETER.

[EricH]

It says that bolts aren't used to calculate the frame perimeter. That's it. Remember, frame perimeter is well above most drives this year, and the drive area is where 90% of the minor protrusions will be (axles, frame bolts, stuff like that).

There has been concern that bolts in the lower frame (say, axles) will be outside the frame perimeter. With this update simply stating that bolt heads won't be counted in the frame perimeter determination, there are a number of possible interpretations:

1) Bolt heads are not counted in determination, so you can't have bolt heads on the frame perimeter sticking out because that's a violation of the frame perimeter restriction. (exception: bumper mounting hardware)

2) Bolt heads on the frame perimeter are fine (due to parts of <R07>), but other bolts are not.

3) Bolt heads sticking outside the frame perimeter are not an issue at all.

I'm guessing they meant #3, but there has been no clarification of this issue at all other than, bolt heads are not counted when determining the bumper perimeter. If they meant #1, then a lot of teams are going to be hurting the first day of events. If they meant #2, then a number of teams may want to look at their drive area and make sure they're OK.

[Tristan Lall]

Originally Posted by Chris is me

Where does it say that? It just says that bolts sticking slightly out of the FRAME PERIMETER are fine, doesnt say these bolts have to be on the BUMPER PERIMETER.

It's because <R16>—and not the definition of frame perimeter—defines the robot rules violation, while <G30> and <S04> are responsible for the corresponding (and potentially redundant) in-game penalties. Despite changing the "determination of the FRAME PERIMETER", <R16>, <S04> and <G30> remain in force and must still be obeyed.

Whatever the frame perimeter is, you must construct your robot within it.

[JesseK]

The GDC made something easier??? Link or it didn't happen!

[Al Skierkiewicz]

By considering both the note in TU 6 and this...

<R16> During normal operation no part of the ROBOT shall extend outside the vertical projection of the FRAME PERIMETER, except as permitted by Rule <G30>.

I believe the intent is that "minor protrusions such as bolt heads, fastener ends, rivets, etc" outside the bumper zone are treated the same as if they were in the bumper zone as R16 references the definition. I think that the restrictions allow robots to be equally inspected. Please note that axles, structures, kickers and other frame parts are not part of the exclusion. Thank you, GDC.

[alectronic]

and in case you still don't believe it....

http://usfirst.org/uploadedFiles/Rob...Update%206.pdf

[martin417]

There is a whole thread already discussing this question. And while I agree that the intent of the update was to allow fasteners to protrude, the words don't say that.

I believe that the GDC wants to maintain a certain "mystique" about themselves and the answers they give.

This forum is intended for rule clarification. To maintain the mystique of the process, we typically refrain from answering "why" questions about game design decisions.

So they tend to be oblique in their answers. If they intend to allow fasteners to protrude, why say something like:

<R16> During normal operation no part of the ROBOT shall extend outside the vertical projection of the FRAME PERIMETER, with the following exceptions: projections permitted by Rule <G30>, and minor protrusions such as bolt heads, fastener ends, rivets etc.

At any rate, if you exclude the fasteners from the determination of the frame perimeter, then said perimeter is defined by the frame members. Anything outside the frame members is, by definition, outside the frame perimeter. The frame perimeter is defined by the outermost vertices on the robot, exclusive of fasteners.

So, any way you want to read it, regardless of intent, it says that ANYTHING outside the frame perimeter is illegal, except as allowed by <G30>. But, <R07> D states that clearance pockets are allowed in the bumper backing for bolt heads etc. so, even though the rules state that it is illegal for fasteners to protrude, it is legal to include clearance pockets for the illegal bolt heads.

For the sake of clarity, I will ask the question more specifically on the forums. I hope that they will be more clear in their answer. This late in the season, the time for mystique has passed. Teams need to know, clearly, what the rules are so they can finish their robot.

[Chuck Glick]

Everyone also is going to need to apply the "common sense rule" when reading this update. This update is not saying "if your frame is 28"x38", but you have bolts that extend beyond this then you are A-ok."

Lawyering the rules is just making people overthink the intent of this update.

This update is saying that the bolt heads or rivets or whatever else might be outside the "frame perimeter" still need to be within the 28"x38" max dimensions. Bumpers are still to be attached to the frame perimiter, but are allowed to have small holes or pockets in the back of them to allow flush mounting to the frame perimeter.

So if you are reading this new update as "hey, we can have bolts and stuff outside the 28"x38" package!" , I'm sorry, but you are mistaken. Make sure you have everything within the 28"x38" to avoid headaches when it comes to inspection time and you learn that your bot is really 28.5"x38.5" just because your bolts protrude a little too much. A half inch may not sound like much, but what if the protrusions in question are your drive axles? Good luck driving now.


Definintions to help understand this update (both are from the ORIGINAL manual):

FRAME PERIMETER:
The polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS attached) that are within the BUMPER ZONE. To determine the FRAME PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

<R07-D>
Each BUMPER segment must be backed by a piece of ¾-inch thick by 5-inch tall piece of plywood. Each piece of BUMPER backing must be a minimum of 6 inches long. Small clearance pockets and/or access holes in the BUMPER backing are permitted, as long as they do not significantly affect the structural integrity of the BUMPER.