Bumper question

[EricH]

Originally Posted by slijin

You're looking for [R33]; if the width of the gap >= 8", then it can only go 1/4" in; otherwise, there seems to be no apparent limit other than your bot itself.

Ah, but if you don't have a bumper in that section, then there is no limit at all! Well, unless you happen to like having two half-robots.

[buildmaster5000]

What defines the bumper zone this year?? In the past, I remember it being from 1 to 7 inches above the ground (2010 excluded. Bumpers were higher that year), but I cannot seem to find where the "bumper zone" is defined in the manual.

Both <R01> and <R29> reference a "bumper zone" for those who are wondering. Please tell me that bumpers are going to be like the height limit last year, waiting for Q&A to open to ask a question that will greatly impact designs...

[the man]

2 to 10 in above the floor.

[Al Skierkiewicz]

Eagle's interpretation is correct. However, in the past this spec was 6" (six) inches.

[slijin]

Originally Posted by buildmaster5000

What defines the bumper zone this year?? In the past, I remember it being from 1 to 7 inches above the ground (2010 excluded. Bumpers were higher that year), but I cannot seem to find where the "bumper zone" is defined in the manual.

Both <R01> and <R29> reference a "bumper zone" for those who are wondering. Please tell me that bumpers are going to be like the height limit last year, waiting for Q&A to open to ask a question that will greatly impact designs...

[R01] actually defines the Bumper Zone as 2"-10" above the ground, just to reiterate what previous posters have pointed out

[Steven Donow]

Originally Posted by KevinGoneNuts

While I have you all here. I also have a bumper question. Attached is a picture of a bumper idea, after reading the rules it seems that this is alright? I want to be 100% sure. Does it seem okay to you?


Attachment 11290

In contrast to this, if the bumper sections on the right and left of the 12" gap were 4", that would be illegal, right?(This was already kinda answered, but just making sure). Because I know Figures 4.1-4.3 aren't exactly drawn to scale, but they imply otherwise.

[Ernst]

Yes. You need a minimum of 8 inches of bumper on each side of each exterior vertex.

[Al Skierkiewicz]

Originally Posted by stevend1994

In contrast to this, if the bumper sections on the right and left of the 12" gap were 4", that would be illegal, right?(This was already kinda answered, but just making sure). Because I know Figures 4.1-4.3 aren't exactly drawn to scale, but they imply otherwise.

No, the 8" specification relates to each side of the vertices in a continuous bumper section. The belief is that something as small as 4" would not protect your robot or another from damage in a collision.

[Cyberphil]

I agree with Al.

The rule states each side of each exterior vertex, which means on one exterior vertex you must have 8" of bumpers on one side and 8" of bumpers on the other side. That means that on the long side of your robot you can have a maximum opening of 22" and on the short side a maximum opening of 12" (assuming your bot is rectangular).

[SenorZ]

I've attached an image from Figure 4-3.
Why is the circled corner not ok?
Is it because
a) it is an interior vertex and cannot be bumper-ed,
b) the adjacent exterior vertex is not covered
c) the straight section of frame connecting it to the exterior vertex is less then 8''

To me it seems like they are saying you can't have a bumper go inside a cut-out. Which is odd.

[Ninja_Bait]

Answer B is covered by the arrow below the one you circled. C is covered in another diagram explaining dimensional rules. A is correct. R27:

Robots are required to use Bumpers to protect all exterior vertices of the Frame Perimeter.

That is not considered an exterior vertex because it is contained in the frame perimeter. The perimeter is defined by the vertical rightmost edge and does not include the inlet.

[GaryVoshol]

Originally Posted by SenorZ

To me it seems like they are saying you can't have a bumper go inside a cut-out. Which is odd.

You can have a bumper-like structure inside your Frame Perimeter (FP), but you can't have a Bumper inside the FP.

The difference is in the weight allocation. Any bumper-like structure inside the FP must be counted in the 120 lbs limit. And if you make them color-coded, so that you have 2 of them, you have to count the weight of both pieces at the same time (additional Mechanisms).

Your robot could look somewhat like the circled area except:
-- the bumper-like structure on the inside of the cutout could not extend past the frame
-- the Bumper could not extend past the vertex

[Al Skierkiewicz]

Quite frankly, I don't know why that interior bumper is outlined as "not OK". The rules say that a bumper must attach to the frame perimeter, which it does, it must be a minimum of 8" on either side of an exterior vertex, can't tell since the drawing is not dimensioned, etc. There do appear to be any rules that prevent interior bumpers. If I find out, I will let you know.

[Rocketeeringer]

I don't think there's a rule expressly prohibiting interior bumpers, but from the diagram and their stress on "exterior vertexes" I would just go with bumpers on the outer corners.

Having bumpers on the inside would limit the already limited space available because of the 8" on each side rule, so maybe they want to give us as much room to work with but having the compromise of the exterior vertex and 8" on each side.

[Joe Johnson]

Originally Posted by Al Skierkiewicz

Quite frankly, I don't know why that interior bumper is outlined as "not OK". The rules say that a bumper must attach to the frame perimeter, which it does, it must be a minimum of 8" on either side of an exterior vertex, can't tell since the drawing is not dimensioned, etc. There do appear to be any rules that prevent interior bumpers. If I find out, I will let you know.

I interpret it this way. The FP does NOT include the inside of the U you are not allowed to have a bumper in there... ...that doesn't count as robot weight. If you want to put bumper in there, knock yourself out, it just has to go in your BOM calculations, weight, ...

Joe J.