Re: Bumper question
 

I thought the bumper should be strictly 8 inches between 2 inches from the ground and 10 inches from the ground?

Last year the rule was 1 inches to 7 inches from the ground total bumper height must be 6 inches if i am not mistaken? At least our bumpers were exactly 6 inches high.

If my bumpers are 5 inches high from the ground and still within the bumper zone, would that be legal?

Re: Bumper question
 

Al, that "not a bumper" makes the frame design illegal due to the bumper mounting rules. Here is my logic sequence. I will use "Bumpers" to designate manual-spec bumpers and "bumpers" to designate non-manual-spec bumpers

1. Both sides of a vertex of the Frame Perimeter must have 8" of Bumpers. [R27]
2. Bumpers must be firmly attached to the Frame Perimeter. [R28-E]
3. The Frame Perimeter definition ([R01] blue box) for the robot in question is a rectangle.
4. Because the bumpers inside the Frame Perimeter are not Bumpers ([R27], Figure 4-3), they are not adequately protecting the Frame Perimeter vertices in question per [R27]. (I know that's kind of a weird thing to say--something that is adequately protected is not considered adequately protected. But, that's the way the rules are written.) This results in a violation of [R27].
5. There is no way to attach 8" of Bumper on the Frame Perimeter and have it be supported as required by [R33] with the design in question.
6. Therefore, because a) [R27] is violated and b) there is no way to turn them into Bumpers without modifying the frame in question to support bumpers as required by [R33] and [R28-E], the robot frame design is illegal.

The Update didn't make the frame design illegal, true. It clarified that it was definitely illegal by declaring, once and for all of 2012, that bumpers inside the Frame Perimeter were not, in fact, Bumpers. The bumper rules take care of the rest.

Re: Bumper question
 

The bumper may be mounted between 2 inches and 10 inches from the ground. However, bumper height is 5 inches (2 stacked 2.5" pool noodles, and a 5" high plywood backing). This gives 3 inches of height in the bumper zone that is not covered by bumpers.

So, if the bottom of your bumpers was mounted 5" off the ground, provided that you built to the rules, then you would most likely be legal. (Subject to inspection, of course.) If the centerline of your bumpers was 5" off the ground, then you'd again probably be legal subject to inspection (5/2=2.5"; 5-2.5"=2.5" at the bottom of the bumpers).

As far as going from one side of the field to the other without hitting bumpers, there are the bridges. You just have to get them tipped to your side.

Re: Bumper question
 

I think you're confusing their height and width measurements. This year as with last year and previous years, bumpers must be backed by exactly 5" tall plywood (R07F 2011, R4.1.6A 2012). This year, the minimum length of bumper coverage on each side of each exterior vertex is 8" (R4.1.6). Last year, the minimum length of each bumper segment was 6" (R07D, note that the rules are actually very different between the 2 years).

Re: Bumper question
 

Guys,
If you run the numbers on the diagonal of a 5" high vertical pool noodle you will find it to be 6"+. If you tilt the robot in crossing the barrier, the bumper diagonal will place the front edge of the bumper above 10" regardless of where the bumper is mounted. Please note that the GDC responded Friday with a Team Update that speaks directly to this condition.

"The carpet, the Bridge surfaces, and Keys are considered the flat floors – and thus are the reference planes for the Bumper Zone requirements. A Robot in a transitory state of crossing onto/off of a Bridge or Barrier is not considered to be on a flat floor."

Re: Bumper question
 

::rtm::
Look legal. Our team is all ways trying to stay in legal and that is our basic bumper desgin
.::rtm::

Re: Bumper question
 

Still need clarification about gaps along a frame edge. Assuming Figure 4-1 in the bumper-rule section, and assuming that the displayed bumper segments are such that the portion covering a given edge is 8" (measured from corner to middle of frame), then is there a maximum length of the remaiming exposed frame, or does the amount of exposure not matter?

Re: Bumper question
 

As long as you have the 8" bumper segments from the corners, there is no maximum length of exposed frame. There is also no minimum length of exposed frame.

Re: Bumper question
 

Well there is a maximum length, since your frame can only be 38" in total. 38 - (2*8) = 22 inches. However, if your frame is smaller, then the maximum exposed part is smaller.

The 8" bumper on corner rule doesn't say anything about what can be in between those corners. It could be an opening (to suck up balls, perhaps?) or it could be an exposed piece of frame. It's whatever your team wants to do within the flexibility of the rules.

Re: Bumper question
 

Will,
Please keep in mind that this part of the bumper rule does change from year to year. More often than not, the bumpers were required all the way around the frame perimeter.

Re: Bumper question
 

The Team Update 2012-01-24 says
But I don't see the updated figure. Did I miss something obvious (I've done that once or twice before 8-) ), or did they forget to include the new figure? Can anyone tell me where to find it?

Thanks!

Re: Bumper question
 

They only posted it in the manual itself, not the Team Update.

Re: Bumper question
 

Ah, I did not attempt to open the manual because the hover text still says "The Robot_Rev-". Now that I've opened it, I see it's actually at Rev B (and apparently includes updates after the 1/13/2012 date given for Rev B in section 4.2).

Thanks for the pointer, Siri.

Re: Bumper question
 

There is a question on FIRST Q&A with an inadequate answer from FIRST.

Q. We are deciding to use a square U frame. So, we have to split the 4th bumper into 2 sections. Because of this, we can't decide how to place "3490" on our Bumper. Should we place the 4 numbers on 1 side, or should we split 34 and 90 across the Bumper. R35 doesn't explain how to handle this situation.

A. Per [R35] team numbers must be "clearly visible from a distance of not less than 100 ft, so that judges, referees, and announcers can easily identify competing Robots." Thus they may not be obscured in any way (disconnected, out of order, rotated, upside-down, mirror imaged, etc).

We are a 4 digit number team and we have a short front bumper on the left and one on the right (many teams do this year). I understand each short bumper must be at least 8 inches long. With the [R35] requirement

Teams shall display their team number on the Bumpers in four locations at approximately 90° intervals around the perimeter of the Robot. The numerals must be at least 4 in. high, at least ¾ in. in stroke width, and be either white in color or outlined in white. Team numbers must be clearly visible from a distance of not less than 100 ft, so that judges, referees, and announcers can easily identify competing Robots.

Each letter will be at least two inches wide. How can I fit 4 numbers in an 8 inches width? If I don't leave any space between them, it will not be very readable. Any ideas?

Re: Bumper question
 

Ed,
The Q&A seems to indicate that splitting the numbers will not be allowed. I agree that the split is likely to cause some confusion. I can only guess/suggest therefore that the numbers on the short side must be less than 3/4" stroke to satisfy the Q&A response. However, if a vertical pool noodle is placed in the corner of said segment, you would have approx 10.5 inches in which to place numbers. I will ask what inspectors will be expected to check for.