Question about bumbers and stuff about our chassis

[Cow Bell Solo]

Our team is planning on putting an angle on the corner of our robot. We are going to extend the bumper past the angle by roughly three inches from the adjacent side (http://www.whitebearlakerobotics.com...hassisplan.doc). According to our interpretation of the rules this is legal because:


* All bumper segments are 6” or longer
* We believe that our bumper configuration satisfies the <R08>-I requirements


We would like confirmation from FIRST on the legality of this configuration(but I have been having problems with the FIRST Q&A.


If this is deemed illegal we would like to put a bumper section on the piece of angle which extends into our robot base. Would this new bumper then be considered part of the bumper zone which nothing could extend over? It is anticipated that the overall configuration of our robot will be a four-sided polygon.

[Vikesrock]

The configuration shown is very similar to one side of 842's robot Carmen which the GDC has stated is illegal. The corner with the angle on it has no way of being protected by bumpers on both sides as required by <R08>-I and clarified in these two Q&A posts:

http://forums.usfirst.org/showthread.php?t=11159
http://forums.usfirst.org/showthread.php?t=11170

There appears to be no way to make the chassis shown legally.

[Scott Hill]

Cow Bell Solo, depending on where you put the pause in reading <R08> J, after "Corners" or after "joints" (GDC, a comma would have been nice), you may not be able to have the filler projection past the lower right corner of the robot as you show in your sketch. J can be read to conclude that such fillers can only be used to fill the space between bumper segments. If you remove the questionable filler projection I think you would be legal with respect to perimeter bumper protection. Both sides of the robot relative to the corner are protected by bumpers and you also meet the following: (from <r08>) ... If implemented as intended, a ROBOT that is driven into a vertical wall in any normal PLAYING CONFIGURATION will always have the BUMPER be the first thing to contact the wall." This sentence is the one most comprehensive and unambiguous metric the game manual includes regarding required scope of robot perimeter bumper protection. In my humble opinion many of the discussions which do not include this item seem to be doing a lot of tail chasing and are doing more to confuse the issue than clarify it.

[MrForbes]

the image as an image file

I agree with Vikesrock. I think <R08-I> gets you...when combined with the Q&A answer....

I. BUMPERS must protect all exterior corners of the BUMPER PERIMETER (see Figure 8 -
2).

2. As indicated in Rule <R08-I>, all exterior corners of the BUMPER PERIMETER must be protected by BUMPERS. Both "sides" of the corner must be protected.

Of course our opinions aren't the Q&A...

[Cow Bell Solo]

Thank you for your responses and We are changing our design of our chassis based on this, We are just going with our backup design. Good thing for planning!

[hillale]

I don't know, I think you could argue that the interior angle part of the bottom right corner of the bot is technically protected by the flat part of the bumper on the left half of the bottom face in the picture. There isn't a way for an opposing bot to come into contact with that corner.

[Vikesrock]

Originally Posted by hillale

I don't know, I think you could argue that the interior angle part of the bottom right corner of the bot is technically protected by the flat part of the bumper on the left half of the bottom face in the picture. There isn't a way for an opposing bot to come into contact with that corner.

Please explain to me how this corner is different than one of the front corners of 842's robot which the GDC has specifically said cannot be legally protected?

http://forums.usfirst.org/showthread.php?t=11170

Based on previously provided information, you have correctly concluded that all exterior corners must be protected by BUMPER segments (Rule <R08-I>). Each BUMPER segment must be a minimum of six inches in length (Rule <R08-A), and must be attached to the BUMPER PERIMETER (Rule <R08-L>). Effectively, this means that an exterior corner of the ROBOT can not be at an angle that is more acute than the coincident corner of the BUMPER PERIMETER. It follows that the example configuration you cited would not be permitted.

The corner in the bottom right of the posted drawing is more acute (45 degrees) than the coincident corner of the bumper perimeter (90 degrees).


At this point with the exception of what "frame" needs to go behind the bumpers I feel the GDC has expressed the intent of the bumper rules in a pretty clear manner. If teams choose design around thier lawyering of the rules and completely ignore the Q&A, they should prepare to be burned. I don't mean to sound like a jerk here, but if a robot with angled intake corners like this passes inspection at my teams regional I will bring most certainly bring these Q&A posts to the Head Inspector's attention and make certain that the team must bring their robot into compliance before competing.

[falconmaster]

Since everyone has determined that we are illegal we are changing our bumpers. Just kidding, we like the critques. It helps us develop our design. We now feel that we will loose that battle so we are changing.

[hillale]

I will agree with you Vikesrock, I'm just curious as to why they seemingly avoid stating that each side of a corner must have 6" bumpers ATTACHED to it at all costs.

[Vikesrock]

Originally Posted by falconmaster

Since everyone has determined that we are illegal we are changing our bumpers. Just kidding, we like the critques. It helps us develop our design. We now feel that we will loose that battle so we are changing.

Heh, sorry to keep dragging you guys into all these bumper thread, but your posted chassis design is a great example that the GDC has ruled on directly.

Originally Posted by hillale

I will agree with you Vikesrock, I'm just curious as to why they seemingly avoid stating that each side of a corner must have 6" bumpers ATTACHED to it at all costs.

Like this?

http://forums.usfirst.org/showthread.php?t=11159

...
2. As indicated in Rule <R08-I>, all exterior corners of the BUMPER PERIMETER must be protected by BUMPERS. Both "sides" of the corner must be protected
.....

I agree that it should be in a Team Update to spread maximum awareness, but they have definitely said it.

[hillale]

Originally Posted by Vikesrock

Like this?

http://forums.usfirst.org/showthread.php?t=11159


I agree that it should be in a Team Update to spread maximum awareness, but they have definitely said it.

That's exactly what I'm talking about, protected by and having physical bumpers attached mean 2 different things to me.