pic: Carmen week1 team 842

[GUI]

..

[redbarron]

I still do not understand why this is not legal.......... If they were to put the bumpers at an angle across those pieces as long as the bumper pieces were at least six inches long, and the corner was not exposed, why isn't this legal?

[Mike8519]

Originally Posted by redbarron

I still do not understand why this is not legal.......... If they were to put the bumpers at an angle across those pieces as long as the bumper pieces were at least six inches long, and the corner was not exposed, why isn't this legal?

Because angled bumpers are not bumpers at all. If they are not on the bumper perimeter they are superfluous padded chassis sections. If you take a piece of string around the outside of the robot (definition of bumper perimeter) the bumpers must be attached to the chassis where the string is.

BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT
(without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine
the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER
ZONE - the string describes this polygon. The BUMPER PERIMETER may extend up to, but cannot
exceed, the maximum ROBOT volume constraints defined in Rule <R11>.

L. The BUMPERS must be fixed to the BUMPER PERIMETER.

[hillale]

Originally Posted by Mike8519

Because angled bumpers are not bumpers at all.

This is not necessarily true

[Mike8519]

Originally Posted by hillale

This is not necessarily true

What I should say is that bumpers on a concave angled portion of the robot are not bumpers. Robots with angled front edges.

Bumpers like http://www.chiefdelphi.com/media/photos/30834 are legal types since the bumper perimeter is along those edges

[GaryVoshol]

Originally Posted by Mike8519

What I should say is that bumpers on a concave angled portion of the robot are not bumpers.

They are bumpers, but they are not BUMPERS. They don't qualify under the <R08> rules, and would not be exempt from weight/size in <R11>.

[jgannon]

Originally Posted by hillale

This is not necessarily true

It's important to keep in mind the difference between bumpers and BUMPERS. Some bumpers are not BUMPERS. Bumpers that are angled such that if extended infinitely would pass through the robot chassis are not BUMPERS, because they are not affixed to the BUMPER PERIMETER. As such, nothing attached to the angled pieces on Carmen's front can ever be considered a BUMPER, so even though the corners of the frame could be protected on both sides by pool noodles and fabric, they won't be protected by BUMPERS, and thus run afoul of <R08-I>.

[rfolea]

I wonder if Inspectors would let this design through due to the potential to damage the field.

With the cantilevered front end, if the robot is struck and the front end dips, the metals will be in direct contact with the flooring, potentially gouging it or catching a seam ...

Maybe consider placing plastic carpet skids on the under side ...

[XXShadowXX]

what are you using pneumatics for?

[Jared Russell]

I have a vested interest in finding out whether this chassis design is legal. It would seem that the bumper rules require (1) that exterior corners are protected by BUMPERS on both sides and all trailer contact is bumper to bumper, and (2) that bumpers can only be attached to the BUMPER PERIMETER.

Unless I'm missing something, both of those conditions cannot simultaneously be met for the front of this robot (Which may or may not be the GDC's intention. Considering that this picture was posted in the Q&A and all that the GDC said was that exterior corners must be protected, it seems like this particular contradiction hasn't occurred to them.)

[MrForbes]

I think it has occurred to them, but they don't answer questions directly, they let you figure out the implications for yourself.

[Paul Copioli]

Fredi,
The robot looks great so far. If you are intending to place 6" of bumper on the internal, angled side then I think you are meeting the intent of the rule. However, the rule as written as a few wierd nuances that may get you in trouble.

Here is what I suggest:

1. Write another Q & A showing the exact picture of your robot with bumpers on all sides you intend to place them.

2. In the Q & A clarify theat the bumpers are all made per the BUMPER rules (plywood, etc.)

3. Specifically ask if the BUMPERS on the angled internal sides are considered BUMPERS or not. Ask if they will be considered in the robot weight or BUMPER weight.



What troubles me is that the bumpers on the internal sides are not really legal BUMPERS becasue they are not mounted to the BUMPER Perimeter. My question is how can you cover all corners with legal BUMPERS if one side of the corner is not part of the BUMPER PERIMIETER?

Good luck with getting clarification. WE decided to go traditional wide body becasue we do not have the patience to deal with non-answers from the GDC on such a mundane subject such as bumpers.

Paul

[Ian Curtis]

Originally Posted by Paul Copioli

What troubles me is that the bumpers on the internal sides are not really legal BUMPERS becasue they are not mounted to the BUMPER Perimeter. My question is how can you cover all corners with legal BUMPERS if one side of the corner is not part of the BUMPER PERIMIETER?

[EDIT]See GaryVoshol's post below, my interpretation is incorrect[/EDIT]

Paul,

My interpretation has always been that an "exterior corner" is one with both both edges (aka sides of the corner) on the BUMPER PERIMETER. This interpretation would be consistent with the images and text in Update #2. I'm working on getting our password to post in the Q&A.

Does this interpretation seem reasonable to anyone else?

[GaryVoshol]

Originally Posted by iCurtis

My interpretation has always been that an "exterior corner" is one with both both edges (aka sides of the corner) on the BUMPER PERIMETER. This interpretation would be consistent with the images and text in Update #2. I'm working on getting our password to post in the Q&A.

Does this interpretation seem reasonable to anyone else?

While your interpretation sounds entirely reasonable, it can't be. That's not how BUMPER PERIMETER is defined:

BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon. The BUMPER PERIMETER may extend up to, but cannot exceed, the maximum ROBOT volume constraints defined in Rule <R11>.

Carmen's front corners with the acute frame angles are outermost vertices, and so by definition are on the BUMPER PERIMETER.

An entirely reasonable interpretation, in my estimation, would be to allow 842 to mount non-standard bumpers on the angled pieces such that with the standard BUMPERS on the side the corners are fully protected. The angled pieces would have to count in the robot size and weight. Whether that reasonable (IMO) interpretation will pass, well I guess it's up to them to gamble or not.

And the GDC is fond of saying, "We do not comment on particular robot designs. Here's the rule."

[384 huband44]

Very awesome looking
Great design work