Team Update #2

[SuperJake]

It is out now...

http://usfirst.org/uploadedFiles/Team%20Update%202.pdf

Big clarification on the bumper rules.

[Tetraman]

I still don't know one question:

If a robot pours a few orbit balls onto an already filled-to-the-top goal, do those balls get scored even if they just fall out? Do the balls that stay on the top for a few seconds then fall out because the trailer moved get scored?

[seanl]

I still don't know one question:

If a robot pours a few orbit balls onto an already filled-to-the-top goal, do those balls get scored even if they just fall out? Do the balls that stay on the top for a few seconds then fall out because the trailer moved get scored?

<G07>
Scores are determined based on the state of the GAME PIECES at the end of the MATCH.

so the fallen balls wont count

[Cow Bell Solo]

There isn't too much of big mind blowing information. But I do agree on the clarification on the bumpers as teams might not of thought of that happening.

I also like that they are going to be posting updates on Tuesdays and Fridays, if I remember correctly they were only released on Fridays last year. I think I might like this as they won't get as lengthy

[cabbagekid2]

<G07>
Scores are determined based on the state of the GAME PIECES at the end of the MATCH.

so the fallen balls wont count

How can that be when the rules say that if a trailer tips over, the points before the trailer was tipped will count?

Edit: Nevermind...both are correct. Scores are calculated at the end unless the trailer tips over.

[Tetraman]

<G07>
Scores are determined based on the state of the GAME PIECES at the end of the MATCH.

so the fallen balls wont count

hmm...I guess I'm over-thinking something. Unhealthy....

thanks

[jgannon]

Is it new for team updates to contain advice toward specific designs?

[Laaba 80]

Can someone explain what they are talking about in the bumper section? I understand the individual rules they stated, but then the next paragraph and the pictures I dont understand. What are they trying to say?

Joey

[Dominicano0519]

i think they are talking about a "wide drive bot" which means the 38" section is the front and the 28" the sides

with a wide drive you could follow the all of the r<08> bumper rules and be able to "engulf" the enemy trailer and constrain its movement

there are many uses for that

[Richard Wallace]

I'll take a crack at that one.

Suppose your robot is built to the maximum <R11> horizontal dimensions 28" x 38". Its BUMPER PERIMETER is therefore (2 x 28) + (2 x 38) = 132 inches, so per the 2/3 rule it must include at least 88 inches of bumpers; that is, it cannot have more than 44 inches of gaps in the bumper. You must leave a gap for the trailer hitch, which is 7" long, so you might think that leaves you with 37 inches of available unprotected BUMPER PERIMETER length, so that nearly one full 38 inch side of the robot could be left unprotected.

But you'd be wrong, because of two other requirements: each bumper segment must be at least six inches long per <R08-A> and the corners must be protected per <R08-I>. Applying these two rules, you find that the maximum unprotected length of BUMPER PERIMETER allowed is 38 - (2 x 6) = 26 inches.

A 26 inch unprotected gap will allow your robot to partially envelope one face or corner of an opponent's trailer, as illustrated by the example drawing at the top of page 3 in Team Update #2.

[Laaba 80]

I'll take a crack at that one.

Suppose your robot is built to the maximum <R11> horizontal dimensions 28" x 38". Its BUMPER PERIMETER is therefore (2 x 28) + (2 x 38) = 132 inches, so per the 2/3 rule it must include at least 88 inches of bumpers; that is, it cannot have more than 44 inches of gaps in the bumper. You must leave a gap for the trailer hitch, which is 7" long, so you might think that leaves you with 37 inches of available unprotected BUMPER PERIMETER length, so that nearly one full 38 inch side of the robot could be left unprotected.

But you'd be wrong, because of two other requirements: each bumper segment must be at least six inches long per <R08-A> and the corners must be protected per <R08-I>. Applying these two rules, you find that the maximum unprotected length of BUMPER PERIMETER allowed is 38 - (2 x 6) = 26 inches.

A 26 inch unprotected gap will allow your robot to partially envelope one face or corner of an opponent's trailer, as illustrated by the example drawing at the top of page 3 in Team Update #2.

Thanks alot for that. Now I understand what they were getting at. They should put your description into the update, because it is much more clear. I dont know if it was just me that couldnt understand it, but you really helped.

Joey

[cbudrecki]

I'm suprised, still no mention of G14 changes.

[AdamHeard]

I would've like if they commented on their being bumpers on the front because of the only 37" inches of unbumpered left, or if there are simply required regardless.

[Ziaholic]

The thing that is confusing me is the 6" section part of the rule.

If they require that a wide-drive 'bot have 6" of bumpers in the front, then how did figure 8-2 come to pass? That figure clearly shows a bumper piece that wraps around a corner. Is that legal because it's more than 90-degrees?

How do you measure the length of an L-shaped bumper? Couldn't you just add up the internal lengths? Theoretically you might be able to make an L-shaped bumper that has 4" on one side and 2" on the other.

Figure 8-2 and the 6" rule are making my head hurt.

[Greg Needel]

The thing that is confusing me is the 6" section part of the rule.

If they require that a wide-drive 'bot have 6" of bumpers in the front, then how did figure 8-2 come to pass? That figure clearly shows a bumper piece that wraps around a corner. Is that legal because it's more than 90-degrees?

How do you measure the length of an L-shaped bumper? Couldn't you just add up the internal lengths? Theoretically you might be able to make an L-shaped bumper that has 4" on one side and 2" on the other.

Figure 8-2 and the 6" rule are making my head hurt.


I had this exact same thought and I asked it on the Q&A. It seems to me that these 2 are contradictory.

I also wonder the same as Jgannon why they are addressing specific robot designs in the rules. It is really starting to make me wonder why they just didn't include an instruction manual with the kit this year saying "we want you to build this"

[Akash Rastogi]

I had this exact same thought and I asked it on the Q&A. It seems to me that these 2 are contradictory.

I also wonder the same as Jgannon why they are addressing specific robot designs in the rules. It is really starting to make me wonder why they just didn't include an instruction manual with the kit this year saying "we want you to build this"

Or like "You really shouldn't build something like this..."

Idk man....I'm not liking this very much still =/

But, I'm still open to changes.

[Paul Copioli]

The 6" bumper picture doesn't make sense. It clearly states in the rules that a bumper can use a pool noodle vertically oriented at the end or bevel the edges. If you bevel the edges you get 3" of bumper sticking out from the bumper perimiter and this is specifically legal. That leaves 3 more inches required to get 6. What they show is 9" of bumper, not 6" (my 4 year old showed me the math behind that one). Since when did 3 + 6 = 6?

[GaryVoshol]

Figure 8-2 is incorrectly drawn, by my interpretation. It shows the red line as the Bumper Perimeter. Then I assume the brown line outside that would be the plywood part of the bumper. If so, it should not be extended along the sides of the robot frame.

Figure 8-2 is illustrating where wood vs noodles go. If you blow it up to about 400% you can see there may be a tiny bit of space in the lower left corner. The wood cannot wrap around the corner - it cannot extend past the end of the frame. (The wood in the lower right corner is shown correctly.) But the noodles can go around the corners, and 8-2 shows a variety of ways that can be done. In fact, it seems to be saying that the noodles must go around the corner, as the upper right corner is marked "Not OK". Noodles may go around the corner as a mitered corner (lower right), butted up against each other (upper left), or bent and enclosed in one piece of cloth (lower left).

This update does not confirm or refute that each face side of a robot must have a bumper. There was an earlier related posting of a robot with a wide opening, no bumper on that side, and the foam extending beyond the end of the edge to protect the corner. Both of those issues still have to be asked in Q&A.

[Laaba 80]

Alright, that makes more sense.

[Paul Copioli]

I edited the original post. I guess my brain wouldn't let me put 3 + 6 = 6 ...

[GaryVoshol]

Paul, my interpretation is that a bumper segment includes the backing board, which must be at least 6" and must be attached to the frame. Noodles can extend farther than that 6", but not less.

[Paul Copioli]

Yep Gary, you are right. Rule R8 sub part J makes this painfully obvious. Oh well.

[Greg Needel]

Yep Gary, you are right. Rule R8 sub part J makes this painfully obvious. Oh well.

it still isn't clear to me how the length is accounted for. I understand about the over hang and that what they are showing is 2 sections of bumper with the smallest being 6 inches, but what happens if you make a single bumper that wraps the corner as in 8-2 lower left. While the wooden joints can't over lap, I would argue that, the example shown is 1 bumper and not 2, which is definitely more then 6 inches.

[JesseK]

it still isn't clear to me how the length is accounted for. I understand about the over hang and that what they are showing is 2 sections of bumper with the smallest being 6 inches, but what happens if you make a single bumper that wraps the corner as in 8-2 lower left. While the wooden joints can't over lap, I would argue that, the example shown is 1 bumper and not 2, which is definitely more then 6 inches.

We have to include the definition of a BUMPER into the updates to get the full picture -- A BUMPER by definition technically has a plywood backing, therefore it is also considered a 'hard' bumper by other clauses of the rule, which may not overlap in the corners. Hence, teams need 6" of a plywood-backed 'hard' BUMPER coming off of the corner of every side. Not only that, rule <R08-M> states that all BUMPERs must be supported by the robot, without gaps. This means you must have a piece of your robot backing the bumpers in every corner.

Hence, when you put all clauses of <R08> together, their drawing is correct and makes sense. We've had to rearrange the frame in some way or another over 8 or so drive train iterations to get it right to comply with the bumper rules :rolleyes: . Next year the bumpers need their own section, lol.

<edit> Of course, as I write this I notice clause <E> that states BUMPERS must not weigh more than 18 lbs, so by what I just said the vertical pool noodles shouldn't count towards the weight of the bumpers. But common sense tells us that the vertical noodles are apart of the bumpers... So eh, perhaps they could re-word it to state that the minimum length of 'hard' bumpers must be 6".

[Hanna2325]

It is really starting to make me wonder why they just didn't include an instruction manual with the kit this year saying "we want you to build this"

ha ha...ya i agree :ahh::confused:

[BenB]

Is the intent of this update to warn us for damage to our robot or the risk of penalty for contacting an oppositions trailer in this fashion?

[JesseK]

Well... what if your robot looked something like this?

...

Sorry about the paint image but if black is the robot's outline and purple is bumpers it would be possible to curve plywood around that curve on the front i believe and it would still satisfy the current rules. Please correct me if I am wrong.

Let's just hope that curved parts don't count as technical corners...then we'll see a whole slew of definitions for a CORNER and all of its ensuing confusion.

Since curves are not edges, I would presume that your drawing is ok for the front of the robot:


Rule <R08-O>
The BUMPER backing must not extend beyond the “edge” of the ROBOT. The backing of
adjacent BUMPER segments must not attach to each other if the attachment would require
that the joint extend into the corner (see Figure 8 – 4).

[Ziaholic]

I'd like to think that an inspector, looking at a curvy bumper that is made well, will pass it. A well made curvy bumper (IMO) would have notched wood and notched angle stock to meet the profile as shown in the figure. If you notch it and form it well, it should meet the "intent" of the rule.


... but ... My team's not going curvy, so I'm very interested in the interpretation of the hard surfaces versus the "vertical" piece of floaty.

I could see that if there were 2 floppy piece-parts, backed with 2 separate boards, and only held together by the cloth and the vertical piece, then both of those pieces should be required to be 6" in length.

But, if my hard-parts were formed together as one piece, and rounded the corner as one rigid unit, with or without the vertical piece (i.e. cut angles in the floaties for an angled joint), then I can count the internal linear distance of the angled piece.

So an L-shaped bumper with 4 + 2 inches of coverage would satisfy the 6" rule ... as long as it's a rigid one-piece bumper.

Assuming I'm right, now they'll have to define what "protecting a corner" means. Minimum 1" of bumper? 2"? 3"?

[edit] if they say 6" is the minimum, then they'll also have to revise figure 8-2.

[sdcantrell56]

So is the consensus that this rule is saying that we must have two 6" pieces of bumper on the front or could it be less as long as it wraps around. If it is saying that we must have a certain amount of bumper isn't this getting a bit ridiculous how much regulation there is in the design. Where is the room for innovation?

[Ziaholic]

... and another thing ... they should give us the 7" trailer hitch linear distance as a gimme. There are not many physical ways to poke into that area, so they should let us include that 7" linear distance as a part of our 2/3rds requirement.

[kbaker159]

I was wondering if this would be allowed. The bumper itself wouldn't be shorter than 6", but the L-bracket in the corner is a hard piece, and it would extend past the corner of the robot. I think it wouldn't fly, but I hope someone can find a work-around here. Curving the ends sounds the best so far.
http://fc56.deviantart.com/fs41/f/2009/009/a/9/FIRST_Bumper_assembly_2009_by_Kroden3D.jpg

[AdamHeard]

So is the consensus that this rule is saying that we must have two 6" pieces of bumper on the front or could it be less as long as it wraps around. If it is saying that we must have a certain amount of bumper isn't this getting a bit ridiculous how much regulation there is in the design. Where is the room for innovation?

The rule and update in no way explicitly mandate this, hence the confusion.

[sdcantrell56]

This is a huge point though and needs to be clarified. Basically I am scrambling to change our robot design to work with this 6" per side requirement and I am really not wanting to change the design that we had. This just seems like too much regulation. I understand wanting to possibly force people in to certain drivetrains but this is seriously limiting ball harvesting and scoring apparatuses as well.

[BJT]

The rules and updates absolutely do say that there needs to be a 6 inch piece of plywood covered with pool noodles and fabric on each side of your ball gathering opening. Those of you thinking like lawyers just haven't figured that out yet.

[hillale]

I don't like this definitely takes a lot out of variety out of potential designs. Not saying we won't adapt and overcome, and it is still shadily defined, but the way the gdc phrased that doesn't foster hope in my mind.

[AdamHeard]

The rules and updates absolutely do say that there needs to be a 6 inch piece of plywood covered with pool noodles and fabric on each side of your ball gathering opening. Those of you thinking like lawyers just haven't figured that out yet.

Where does it say this?

[BJT]

in the rules, all of them. but that is just my interpretation, which thus far has not needed any updates for clarification. I could be wrong, but I haven't been yet. I would like a wider opening on the front of our robot too so I hope you are right.

[kbaker159]

After reading the rules some more, I find that a bumper segment can't be shorter than 6", but that the backing (plywood) doesn't have to be in complete segments within each bumper segment. IMO, the segment is defined as a complete piece of bumper held together by either plywood, pool noodle, or both. In this way, I think a bumper with pool noodles that wrap around the corners, no cuts, and attach with 2 pieces of plywood, so long as the entire SEGMENT fits in the 6-38 inch requirement, is allowed. Correct me if there is something that blatantly prohibits using multiple pieces of backing, but I believe this is legal under the rules.

[MrForbes]

I think I read the same rules you did, and came to a different conclusion...how about a rule that says either "there must be bumpers on all sides of the robot" or "bumpers are not required on all sides of the robot". We're engineers, not lawyers.

[Gdeaver]

This update seam's to emphasize that the GDC does not want any robot to trailer contact other than bumper to bumper. It seams very clear that for measuring the bumper length the plywood or AL frame should be used. Not pool noodles. It is also clear that for a rectangular bot every corner must have at least 6" of bumper in each direction.Those who have planed to use the entire front face of a robot for ball gathering have a problem. This means that depending on orientation, The maximum ball entry dimension is either 26 or 16 ". With the limited maneuverability of the robots, running down balls is going to take great driver skill. For those who have chosen the 28" dimension for the front, good luck running down a ball with a 16" max slot. It's not that much better for the 26" either. This update also lets every one Know that in a trailer to robot collision, the trailer can enter into the robot. This may impact some teams design for a ball sweeper mechanism. The diagram in the update does not show the distance the trailer would penetrate into the robot with full pool noodle compression. It would be prudent to make sure that no part of the robot other than bumper can contact the trailer when there is a collision with maximum trailer penetration and pool noodle compression. This will affect our ball sweeper roller design a little.

[DonRotolo]

This may impact some teams design for a ball sweeper mechanism. I wonder, if we made the sweeper robust enough, could we legally sweep in an opponent?:D

Seriously: I do not see any way where I could protect the corners while not having a bumper on each face of the robot with at least 6 inches of hard backing. 26" is about enough for a decent sweeper though.

I agree with squirrel: We're engineers, not lawyers dangnabbit.

Don

[Hadi379]

My interpretation is that this update's intent is to stress the importance of protecting the field elements (trailer is a field element). If your opening was any wider than the 26" wide opening, you may damage the pvc tubing that is attached to the trailer by overlapping the trailor and contacting the posts. Both scenerios bring you within inches of the post circle.

I do not think they are leaning towards a specific design because if you were going to use a narrow chassis, then overlapping or damaging the posts shouldn't be an issue due to the fact that a 26" opening isn't feasible. Therefore, they only showed us a drawing for the wide chassis orientation.

Now if my interpretation is correct, which I'm not exactly sure to be honest because this is just my opinion, then I would think with a narrow design, one would be able to wrap a bumper around a front corner as long as the total segment length is 6" or more.

My reason for this is as follows:

The maximum bumper perimeter is 132". 2/3rds of 132 is 88 inches. If you cover both 38" sides, which equals 76", then you cover the rear, leaving a 7" gap for the trailer tongue, then you've covered an additional 21". These two combined equal 97". Therefore, you have covered 2/3rds of the perimeter.
You still need to add bumpers to the front, and that is where you wrap around the corners to meet this part of <R08>:

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.


I may also be thinking this rule, but its their fault......LOL:ahh:

[Nuttyman54]

See this Q&A post (http://forums.usfirst.org/showthread.php?t=10959) for clarification...it would have been nice if they included the last few lines in the update...

[Paul Copioli]

Here is my problem. I do not like to read the rules as a lawyer and I thought I wasn't. To me, the GDC is lawyering the rules. Here is why:

Nowhere in the rules does it say the entire bumper has to have the plywood backing. It does say a bumper consists of a plywood backing, etc. If I have a legal bumper in my hand, and this year that bumper can be beveled, how long is it? Where do I measure it? At the outside edge? At the plywood?

Before you answer please see rule R8 sub part N as I placed it exactly below:

"BUMPERS may extend beyond the BUMPER PERIMIETER by up to a maximum of 3-1/2 inches per side. "Hard" parts of the BUMPER (i.e. plywood backing, fastening system, and clamping angles) may extend up to a maximum of one inch beyond the BUMPER PERIMETER. Only "soft" parts of the BUMPERS (i.e. pool noodles and cloth covering) may extend more than one inch beyond the bumper perimeter."

This rule clearly indicates the beveled pool noodle is part of the BUMPER. They state it is the "soft" part of the BUMPER.

I don't care either way, but if they want the plywood part of the bumper to be at least 6" long, then why didn't they just say it.

If this update did not come out, my team would have had illegal BUMPERS and would have had no idea why. That is my basic issue.

[GaryVoshol]

I agree with Paul. I can see their point that a bumper assembly includes backer board, noodle and cloth, plus optional corner protection. But wouldn't it be so easy to say, "All three parts must be at least 6 inches"?

They tell you that 2/3 of the perimeter must have a bumper. Nowhere does it say that this 2/3 must be distributed along part of every side of the robot - and that still isn't conclusively stated anywhere. If that's what they meant by "protecting the corners" they should have said so. Teams' interpretations whether an extra bit of noodle going past the corner meets this provision shouldn't have to be guesswork.

I'm working on a concept to avoid this kind of thing in future years' rules. I've yet to flesh it out. But I hope something can be done. I know from the OCCRA Committee that writing down your concept and getting it across to all your readers is difficult.

[GaryVoshol]

I was wondering ... but the L-bracket in the corner is a hard piece, and it would extend past the corner of the robot ... In previous years this would not fly. You couldn't have additional hardware of any type on the back side of the board, except for the fastener that came through the board. But you know the caveat about last year's rules.

And I just found it:
O. The BUMPER backing must not extend beyond the “edge” of the ROBOT. The backing of adjacent BUMPER segments must not attach to each other if the attachment would require that the joint extend into the corner (see Figure 8 – 4).(emphasis mine)

[Richard Wallace]

... if they want the plywood part of the bumper to be at least 6" long, then why didn't they just say it.

If this update did not come out, my team would have had illegal BUMPERS and would have had no idea why. That is my basic issue.I think they did say it, Paul. Taken together, the language quoted below and the section view shown in Fig. 8-1 seem pretty clear to me. A cross section taken anywhere through the bumper segment must include all of the elements shown in the figure, and the minimum segment length is 6 inches.BUMPERS must be constructed as described below and illustrated in Figure 8 – 1.

A. BUMPERS must be built in segments, with a minimum length of six inches, ...

[Paul Copioli]

Richard,

So the part of the BUMPER that is beveled and sticking out of the BUMPER PERIMETER is nto a BUMPER? If not, then does it count for robot weight or BUMPER WEIGHT?

Your argument (and the GDC too, BTW) is like saying a plane must have wings, but the cross section of the plane that doesn't have wings is not part of the plane ... c'mon if that is not splitting hairs, then I don't know what is.

Paul

[GaryVoshol]

Subsection J of <R08> says that bumpers MAY have additional bits of noodles extending to protect the corner. It doesn't say MUST. So there must be other ways of doing it to comply with subsection I - but what are they?

[Richard Wallace]

I interpret the term "cross section" (as used in the rule) to mean a section taken by a plane perpendicular to the BUMPER PERIMETER. In the corner regions, "cross section" is not uniquely defined, because the BUMPER PERIMETER has a singularity (cusp) at each corner. So Fig. 8-1 cannot be applied to corners, and therefore special rules for corner protection are needed. These are provided by <R08-J>.

I agree with Gary; the word MAY in <R08-I> should be replaced by the word MUST or SHALL.

[Bochek]

Just to add to this thread:

There is a Q&A post here (http://forums.usfirst.org/showthread.php?t=10959&highlight=bumpers) that clarifies the minimum length discussion.

[johnr]

My head hurts. Ok, so in the drawing of this update,the footprint of the robot could not get any bigger? What i am trying to ask is as you build upwards, you could not build over the indentation because you would break your bumper perimeter?

[Mike8519]

My head hurts. Ok, so in the drawing of this update,the footprint of the robot could not get any bigger? What i am trying to ask is as you build upwards, you could not build over the indentation because you would break your bumper perimeter?

The definition of Bumper Perimeter is defined as taking string along the outermost vertices of the robot. Once your bumper perimeter is defined in that manner, you may not go outside of it with any part of your robot. An indentation in the robot (even if bumpers are built on it) does not count as the bumper perimeter and may be built over. Bumpers not placed on the bumper perimeter (the indentation) are superfluous and not required by rules.

[sanddrag]

I submitted a post to the Q/A that I believe covers most if not all of our questions: I've copied it as follows. I hope they reply with more than "Please Refer to Team Update #2".

Rule <R08-A> states that "BUMPERS must be built in segments, with a minimum length of six inches, and a maximum length that does not exceed the maximum horizontal dimension of the ROBOT."

1. What defines a bumper "segment?"
2. From where is the length of a bumper "segment" measured?
3. Is the bumper that wraps around the left rear corner of the robot in Overhead View Figure 8-2 in the Robot Manual considered a single bumper "segment"?
4. May a 6-inch-long bumper "segment" wrap around a corner, in any proportion, such that for example 2 inches of the 6-inch segment may exist on one side of the robot, and 4 inches exist on the adjacent perpendicular side of the robot. Is this still considered a single "segment" for the purposes of satisfying <R08-A>?

Rule <R08-I> states "BUMPERS must protect all exterior corners of the BUMPER PERIMETER".

1. What defines a "corner?"
2. At what radius is a "corner" no longer considered a "corner"?
3. From which direction of contact must corners be protected?

[Tristan Lall]

This part of the rule could definitely have been written better and clarified better (in the update and the Q&A posts).

To me, it looks like FIRST has offered an interpretation of the bumper length specification that is more restrictive than in past years. Given the similarities in phrasing (compared to 2008), and the lack of an explicit statement describing this, I doubt that it was intentional.

In 2008, the rules required that "each STANDARD BUMPER segment must be a minimum of 6 inches in length". There was no guidance as to what "segment" meant, and I suspect that most inspectors used the simple, obvious rationale that a segment was a piece of bumper that could be removed from the robot on its own. That also meant that the length (measured in some reasonable fashion) would be at least 6 in.

For the 2009 season, FIRST says that "BUMPERS must be built in segments, with a minimum length of six inches", but also says that "[c]orners and joints between BUMPER segments may be filled...by wrapping the pool noodles around the corners". By speaking about joints between segments, and wrapping the pool noodle around that joint, it's apparent that FIRST is interpreting a segment to mean the piece of plywood, not the entire piece of bumper. Also, by saying "minimum length", it's unclear whether they mean for the length of bumper segments to be measured at the smallest dimension (i.e. the minimum length, which is probably along the perimeter), or if they're just rephrasing the old rule, which seemed to allow the measurement of length to be made across any reasonable dimension (presumably the largest dimension, to give the benefit of the doubt to the teams). Given the specific permission to use bevelled bumpers, this could have significant consequences.

In fact, you could argue that the meaning of "BUMPERS must be built in segments, with a minimum length of six inches" is to specify that each bumper must be composed of segments—maybe one or more, maybe more than one—and to also make a separate requirement that the entire bumper must have a "minimum length of six inches". That definition seems less likely, given the rest of the rule and past usage, but I don't think that there's anything that makes it strictly incorrect, or outright implausible. While I don't favour this alternative interpretation, I don't think I could really fault anyone for coming to it.

Unfortunately, I can't figure out a way to rationalize the GDC's response to FRC1114's question (http://forums.usfirst.org/showthread.php?t=10959), with my preferred interpretation—it does work with the alternative interpretation, however. All of the other statements by FIRST (the rule, the update, the response to FRC1458 (http://forums.usfirst.org/showthread.php?t=10942)) seem to be consistent (only) with the first interpretation, but by saying that "[t]he length of the the bumper assembly that includes ['a solid plywood backing (as well as the pool noodles and fabric cover)'] is what determines the "bumper length", FIRST seems to be favouring the overall dimensions (maybe even with segments taken together), rather than the minimum dimensions (with segments taken separately).

I don't care either way, but if they want the plywood part of the bumper to be at least 6" long, then why didn't they just say it.Ultimately, I'm wondering the same thing as Paul: if it's important, why not be precise? And if it's not important, just state that inspectors may use broad discretion in permitting bumpers that are not strictly compliant, but which are likely to function adequately.

Although I'm definitely grateful for some of the improvements that were made in the bumper specifications since last year, it looks like there are still some kinks to be worked out in this year's rule.

[aaeamdar]

First, it seems clear to *me* that Team Update 2 is wrong - the rules as they stand now would allow for (probably) a 34 inch opening*. Hopefully we'll see more clarification on this issue from FIRST, but let's assume that you use "wraparound" bumpers to cover your front corners, which would come 2'' onto your front side. In theory you could design them to be less than that, but 2'' seems like a pretty practical limit. The problem as I see it is the chassis - how are you going to design a solid, robust chassis in significantly under 6''? And remember, no adamantium.

Second, to those unhappy with this rule - I understand your frustration. Coming up with a great design and then seeing it foiled by a rule change is a frustrating experience. However, try to keep in mind the intent of the bumper rules in general. The intent is to minimize damage to field elements and robots so that we can continue playing the game. If the bumper rules were lax enough that they didn't restrict overall robot design at least a little, it's hard to imagine that they would provide adequate protection. Also, keep in mind that everyone is in the same position here - so it's restricting your design, but it's also restricting everyone's, so at the end of the day it's just making you think more, and a wash in terms of the game.

Third, a friendly suggestion, particularly to new teams: FIRST changes the rules around pretty much when they feel like it and how they feel like it. Sometimes rule changes that (from my perspective) were obvious necesities from the beginning were not implemented until week 6 of build, or were never implemented. So, the suggestion is: design your bumpers (and your robot in general) so that you're not even close to violating these rules. That way, if they change the rules a bit, you won't be scrambling around Monday night in a panic.

Good luck to everyone, and hope things are going well after one week
Paul

[cnepo]

I personally could not find this in the rule book and maybe I'm missing it but is there a height restriction on the bumpers?

Thanks for any of the help you can provide!

[wilmo]

Charles,

Definitions:

BUMPER ZONE – the volume contained between two virtual horizontal planes, one inch above the
floor and seven inches above the floor.

R08:

P. BUMPERS must be mounted to the ROBOT within the BUMPER ZONE, and must remain
there. The BUMPERS must not be articulated or designed to move outside of the BUMPER
ZONE.

Wilmo

(we are all tired :P )

[acdcfan259]

Just some clarification needed. Each side of the robot has to have bumpers on it, right?

[MrForbes]

Yeah, we think so, but maybe not....hopefully we'll get some substantial clarification.

Better plan on putting bumpers on every side, 6" minimum length at each end at least.

[Richard Wallace]

The GDC has provided further clarification in this Q&A response (http://forums.usfirst.org/showthread.php?t=11159).

[Elgin Clock]

So, looking at all the responses in the Q&A & the pics & reading the pertaining rules associated with this fiasco, it clearly means that the 6" min is the length of the wood backing only, so thus a bumper with a soft noodle making the corner extend the diameter of a bumper which is really a bumper 6"+~2.5" long is defined as a 6" bumper.*
*(The ~2.5" being the diameter of 1 pool noodle in the vertical position for protection of the corner of the bot)

Why can't they just say that?

It's like buying a 2x4 piece of wood.
We all know it's not really 2" x 4" but that's just the name of the darn thing.

Why can't they just come out & say that a 6" bumper is either 6" total length without any overlap past the wood, or a 6" piece of wood with the only allowed overlap being the 1 or 2 pieces of vertical pool noodle(s) at the ends.

I'm glad I (think I) understand what they are trying to say, but why must they be so roundabout sometimes in the way they say things?

[MrForbes]

The GDC has provided further clarification in this Q&A response (http://forums.usfirst.org/showthread.php?t=11159).

This finally does state the fact that we need bumpers on all sides of the robot.

"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."

[Hadi379]

I still would like to know if we can wrap a corner with a bumper and have that considered as one segment....in an "L" shape

[MrForbes]

It appears not. See part O of rule <R08>

O. The BUMPER backing must not extend beyond the “edge” of the ROBOT. The backing of adjacent BUMPER segments must not attach to each other if the attachment would requirethat the joint extend into the corner (see Figure 8 – 4).

To make the bumper wrap around a corner, you would need to extend the backing past two edges of the robot.

[Elgin Clock]

This finally does state the fact that we need bumpers on all sides of the robot.

"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 believe that was a direct response to the angled configuration that was posted by that person as an example.

Which makes complete sense, because common sense tells you that if you do build a robot that wants to hug the goal, you can only touch the goal with bumper on bumper contact, so the face of your bot that will touch the goal will need a bumper.

[MrForbes]

Elgin, I think it's a more general response....it appeared to me that they did not give a specific answer for that design. I'm starting to sound like a lawyer, I better stop posting on this thread

[Jared Russell]

I wish the GDC would have just come out and said whether 842's chassis design was legal.

[rfolea]

Why can't they just come out & say that a 6" bumper is either 6" total length without any overlap past the wood, or a 6" piece of wood with the only allowed overlap being the 1 or 2 pieces of vertical pool noodle(s) at the ends.

I'm glad I (think I) understand what they are trying to say, but why must they be so roundabout sometimes in the way they say things?

That Q&A was mine.

I too was struggling with the obtuse language, but it is VERY clear now: The length of a "Bumper" is the any length that includes all three elements: the wood backing, foam and cover.

So angular foam protrusions and vertical noodles are NOT part of the bumper length (they don't include the wood backing).

This explains why the 9" bumper on the front of the robot in the figures is measured as 6".

Bottom Line: Bumpers are REQUIRED in TWO places:

1. On the front, two 6" segments minimum.
2. on the rear (or wherever the trailer hits the robot when it swings around.

[GaryVoshol]

Bottom Line: Bumpers are REQUIRED in TWO places:

1. On the front, two 6" segments minimum.
2. on the rear (or wherever the trailer hits the robot when it swings around.Make that THREE:
3. On the sides adjacent to the front and back bumpers. (Because both sides of the corner must be protected with a bumper.)

[JesseK]

Dave likes to remind us every year at VCU that we're really solving problems that are very similar to the same problems NASA has to solve. I can't wait for this year's speech, but until then I think about the bumpers like this:

All of the little Mars rovers had airbags that deployed and overlapped the corners of the tetrahedron. The 'hard' bumpers may not have been allowed to overlap each other due to NASA's testing and requirements, but obviously all of the corners had to be covered by a bumper. There were probably other requirements that were derived from testing as well. If the bumper system failed in any way shape or form, the free fall from X number of miles out would have compromised the entire multi-million dollar mission.

We complain that there are very strict bumper rules, and each individual rule appears to contradict other rules when put into a certain perspective. However, the only perspective that matters is the big picture: the GDC wants less damage done to their fields, their field components, and teams' robots. Yes the rules limit the design a bit, and yes some of the requirements appear unclear when put into the myriad of perspectives. How is that any different from the real world of engineering?

[Cory]

We complain that there are very strict bumper rules, and each individual rule appears to contradict other rules when put into a certain perspective. However, the only perspective that matters is the big picture: the GDC wants less damage done to their fields, their field components, and teams' robots. Yes the rules limit the design a bit, and yes some of the requirements appear unclear when put into the myriad of perspectives. How is that any different from the real world of engineering?

Because it would have been far easier to say "all sides of your robot must have bumpers", "all corners must be protected by bumpers", "a single bumper segment cannot span both sides of a corner", "a bumper segment has a plywood backing a minimum of 6" long, with pool noodle overlapping the edge (unsupported) no more than 2.5 inches", and "bumpers must cover 2/3 of the robot's perimeter"

There really wouldn't be any confusion if the rules had been more specific. We're always asked not to lawyer the rules but our team hasn't felt like we could be certain our bumper configuration would meet the intent (or word) of the rules without doing so.

[AdamHeard]

Because it would have been far easier to say "all sides of your robot must have bumpers", "all corners must be protected by bumpers", "a single bumper segment cannot span both sides of a corner", "a bumper segment has a plywood backing a minimum of 6" long, with pool noodle overlapping the edge (unsupported) no more than 2.5 inches", and "bumpers must cover 2/3 of the robot's perimeter"

There really wouldn't be any confusion if the rules had been more specific. We're always asked not to lawyer the rules but our team hasn't felt like we could be certain our bumper configuration would meet the intent (or word) of the rules without doing so.

Exactly.

Did anyone else have to modify frames that had already been cut? We did. Some people may say we we're being "Greedy" and thinking we could get away with not having bumpers on all sides. But if we arrived at a regional and many teams were legally competing without them, we'd be terribly upset.

[Elgin Clock]

Some people may say we we're being "Greedy" and thinking we could get away with not having bumpers on all sides. But if we arrived at a regional and many teams were legally competing without them, we'd be terribly upset.

It will happen, so be prepared to be upset.
The teams would not be competing legally btw.
They (inspectors, staff, etc,) would rather have a team compete being illegal, than miss out on the experience because it is too much work to modify something on a lone practice day that they spent 6 weeks making.
They will be told that they are in violation & be given time to fix it, but if it's not perfect, they will be able to slide unfortunately.
I've seen it happen before & it will happen again.

Would you deny a team to compete if they made the effort to fix their problem that practice day? I would say they gave a good effort, & give them credit for trying & allow it as long as it wasn't a clear safety hazard - I know that's a huge grey area, but it will happen.

On the other hand, would you tell them they couldn't compete at all if they didn't care, & went on the field knowing they were illegal without giving any effort to fix it? I would deny them that priviledge if they were arrogant about it, or just didn't care.

It's something to shudder at thinking about it, but you get used to it; while hopefully not getting too stressed about it, & realizing it just comes with the territory.
The best thing to do, is help teams if you have the resources at your regionals to be fully compliant within the rules if they misinterpreted something.
We have all misinterpreted som rules at some time or another, so just give them the benefit of the doubt, & help them if they do not comply with the rules.
If they refuse to change, then bring it up with an inspector & let them handle it.

[SuperJake]

<edit> Elgin beat me to it by a couple of seconds, but I wanted to add my sentiment anyway </edit>

Exactly.

Did anyone else have to modify frames that had already been cut? We did. Some people may say we we're being "Greedy" and thinking we could get away with not having bumpers on all sides. But if we arrived at a regional and many teams were legally competing without them, we'd be terribly upset.

My biggest problem with issues like this is that there have been several occasions where FIRST has had a rule going into the Regional Competition that has changed because too many teams show up at the regional in conflict with the rules.

I will be quite disappointed if this rule is made legal during the regionals because some other teams decided to ignore the rules.

[AdamHeard]

It will happen, so be prepared to be upset.
The teams would not be competing legally btw.
They would rather have a team compete being illegal, than miss out on the experience because it is too much work to modify something on a lone practice day that they spent 6 weeks making.
They will be told that they are in violation & be given time to fix it, but if it's not perfect, they will be able to slide unfortunately.
I've seen it happen before & it will happen again.
Would you deny a team to compete if they made the effort to fix their problem that practice day? I would say they gave a good effort, & give them credit or trying & allow it as long as it wasn't a clear safety hazard.
On the other hand, would you tell them they couldn't compete at all if they didn't care, & went on the field knowing they were illegal without giving any effort to fix it? I would.
It's something to shudder at thinking about it, but you get used to it; while hopefully not getting too stressed about it, & realizing it just comes with the territory.
The best thing to do, is help teams if yuo have the resources at your regionals to be fully compliant within the rules if they misinterpreted something.
We have all misinterpreted som rules at some time or another, so just help them if they do.
If they refuse to change, then bring it up with an inspector & let them handle it.

I'm familiar with the instances you're talking about, hopefully they would consider bumpers easy enough to add that they won't go back on this rule. Ideally, they'd let teams slide on bumper mounting (maybe not exactly on bumper perimeter, not supported along the whole length, etc..) rather than just let teams go without bumpers on all sides.

[Aren_Hill]

With all this stuff happening in regards to bumpers, i'm really wondering how many teams are even keeping track. I can picture quite a few ignorant teams showing up with non legal bumpers simply for not checking the updates and QandA system. I hope inspectors will have those teams make the bot legal before they can play qualifiers, otherwise everyones headaches trying to figure out bumper rules had no point when they could've just ignored them and still played.

last year i saw a bot with 2 van door motors, 1 of them being from 2006 and duct tape quite evident in quite a few places, and the bot still played, i didn't mention anything to the inspectors.

[Elgin Clock]

I'm familiar with the instances you're talking about, hopefully they would consider bumpers easy enough to add that they won't go back on this rule. Ideally, they'd let teams slide on bumper mounting (maybe not exactly on bumper perimeter, not supported along the whole length, etc..) rather than just let teams go without bumpers on all sides.

This is true. Unlike some previous years where bumpers were optional, so if you had a problem with them you could just take them off if they didn't comply, I hope by the end of week 6 that EVERYONE is on the same page of what is allowed & what is not regarding bumpers.
(I saw one team show up with duct tape over pipe insulation wrap on the side of their bot one year thinking that would pass as a bumper. It didn't, so they just took them off.)

The only reason I say this, is that a bumper is probably not the easiest thing to fabricate for teams with bad ones at a regional event. (Relatively speaking I guess. It's easier to make a set of bumpers than re-design a whole drivetrain, but you know what I mean...

When in doubt, bring two (or more) pre-made configurations of your proposed bumper designs for your specific robot, & ask the inspectors which one is legal at your first competition if you have any questions.

It will HAVE to be goverened on a case by case basis in that regard ONLY at the events in my opinion, unless the GDC starts taking submissions of pictures of every team's bumper designs & approving them on a case by case basis now (before shipping).

I don't want to see the GDC have to nit-pick now & do that, as they have already spent enough time on this issue as it is.

[AdamHeard]

When in doubt, bring two (or more) pre-made configurations of your proposed bumper designs for your specific robot, & ask the inspectors which one is legal at your first competition if you have any questions.


That would actually require us to bring two different frames, and possible two different mechanisms; that's how much the bumper rules affect design.

I think we'll be bringing some plywood, some pool noodles, and some nice bright orange bumper fabric. Hell, maybe we'll even make some 6" sections to hand out; first 10 teams to fail get 6" free!

[tiger192]

Rule <R18> secion E states "The Trailer Hitch must be placed such that, as the TRAILER swings from side to side, the first contact between th TRAILER and ROBOT is BUMPER-to-BUMPER and not TRAILER-tongue-to-BUMPER."

Are there any other teams having a problem with this in their designs? With our hitch on a 28" side of our design which doesn't include 90 degree corners on the back, we can not seem to find a way to make our concept account for the trail bumpers hitting the robot before the tongue does.

[Akash Rastogi]

When in doubt, bring two (or more) pre-made configurations of your proposed bumper designs for your specific robot, & ask the inspectors which one is legal at your first competition if you have any questions.


This is a good plan...but I agree with Adam's and Corey's statement that it shouldn't come down to that in the first place. Kinda like saying "oh let's take two robots and see which one they say is legal we'll use."

But idk, the rules always seem this ambiguous to me anyway.

My pov, it shouldn't have to come down to making two configs. But you gotta roll with the punches I guess.

[JHSmentor]

The GDC has provided further clarification in this Q&A response (http://forums.usfirst.org/showthread.php?t=11159).

while I agree that this response from the GDC answers nearly all concerns, it doesn't answer the question of what they consider a corner. Is it any angle between two pieces of plywood. Is it simply a change of direction? Is it something greater than 45*? Like the one picture in the rule book shows, there is a continuous section that rounds a 120* angle corner. Now - this corner appears that it probably has a 6" side on one part and a longer side on the other. So, I'm assuming this is a corner. I'm also assuming, however, that if this was a continuous arc in the frame rather than a sharp corner or change of direction, and if you could bend the plywood to match, then the total segment length could be 6" around the bend. Would this be a feasible design? I have no idea - never tried to make a roundish robot or even part of one and I have never tried to bend plywood. It may be physically impossible and a moot point.

So, is this relevent? Yes - if it were possible to do a curved section (or round robot for that matter) then it leaves open more flexibility.

Also, can someone please explain to me what is meant by "lawering" the rules? How can simply trying to understand the rules properly so that you know your appropriate limitations for your design be considered lawering? Anyway - just want to understand since I have seen it used in many different contexts.

[hillale]

Also, can someone please explain to me what is meant by "lawering" the rules? How can simply trying to understand the rules properly so that you know your appropriate limitations for your design be considered lawering? Anyway - just want to understand since I have seen it used in many different contexts.

Certain people consider translating the rules into a playable robot, while finding ways to make it more competitive than others might think the rules allow, to be lawyering.

[JHSmentor]

Certain people consider translating the rules into a playable robot, while finding ways to make it more competitive than others might think the rules allow, to be lawyering.

okay - that makes sense. I can agree with that - as long as it applies to the intent of the rule. Correct?

So, in the case of the 6" long bumper rule - is the intent to allow for sufficient bumper to bumper contact to eliminate/reduce damage between the two contacted surfaces or is it to increase the design challenge? or something else?


I think it's just a rule to dictate proper protection. If someone can come up with a good (although potentially complicated) design that will allow them a wider opening (>16") on the 28" wide side of the allowable robot design then I call that good engineering.

I'm only saying this because that's what I want to do - engineer my way out of this 16" limitation if I can. I don't want to be called a cheat or something because others might think that I'm stretching the intent or letter of the rules. (BTW, I'm not saying that anyone will, but that is a fear that I have).

Of course, part of a good design (particularly for this case with the bumpers) would be that, even though the design would be fresh and innovative, would be very clear that the rules were followed to the "T" without question.

[hillale]

okay - that makes sense. I can agree with that - as long as it applies to the intent of the rule. Correct?

So, in the case of the 6" long bumper rule - is the intent to allow for sufficient bumper to bumper contact to eliminate/reduce damage between the two contacted surfaces or is it to increase the design challenge? or something else?


I think it's just a rule to dictate proper protection. If someone can come up with a good (although potentially complicated) design that will allow them a wider opening (>16") on the 28" wide side of the allowable robot design then I call that good engineering.

I'm only saying this because that's what I want to do - engineer my way out of this 16" limitation if I can. I don't want to be called a cheat or something because others might think that I'm stretching the intent or letter of the rules. (BTW, I'm not saying that anyone will, but that is a fear that I have).

Of course, part of a good design (particularly for this case with the bumpers) would be that, even though the design would be fresh and innovative, would be very clear that the rules were followed to the "T" without question.

I agree with your interpretation on the rule and I really hope that's the way it is clarified (if it ever is). However, given the exact design shown in team update 2, I'm not sure what's going to happen.

[Gdeaver]

It's amazing how First is a microcosm of the real world. And as such it gives the students a chance to play the game of life without the threat of job loss or financial ruin. Team's don't have to like the rules, they don't have to make sense in you specific case. It doesn't matter what you think they should be or how they should be interpreted. The rules are the rules. You must follow Z RULES. You must be in compliance. Compliance is WHAT EVER THE RULE ENFORCERS SAY THEY ARE. PERIOD.
I'm in the construction business and a good part of my life is spent figuring out how to keep my jobs and business in compliance. It's a never ending battle to stay on top of all the rules and the interpretations of them. If I fail to to do it the financial repercussions could bankrupt me. So I would suggest teams take a conservative interpretation of the bumper rules and make your robot fit the bumper restrictions. Once again you don't have to like them. One the worst things that can happen is to show up practice day and not be in compliance. Been there, it's not fun.

[MrForbes]

I think we'll be bringing some plywood, some pool noodles, and some nice bright orange bumper fabric. Hell, maybe we'll even make some 6" sections to hand out; first 10 teams to fail get 6" free!

Now you're talkin....that's a great idea!


:)

[hillale]

The rules are the rules. You must follow Z RULES. You must be in compliance. Compliance is WHAT EVER THE RULE ENFORCERS SAY THEY ARE. PERIOD.

I'm just really curious what the RULE ENFORCERS are actually saying. If they wanted us to only have a 26" opening on a wide-based robot, why not tell us that specifically? There is always going to be some gray area. Whether this is to leave space for innovation or to have the gray area defined by the respective regional referees, I'm not sure in this case. I'm hoping it's for the prior, but the past does not shed positive light on that path.

So I would suggest teams take a conservative interpretation of the bumper rules and make your robot fit the bumper restrictions.

I'd much rather build something that plays the game well, thinks outside the box AND adheres to all of the existing rules (updates included). I always find those to be more inspiring... to everyone.

[Gdeaver]

The GDC has decided to expose the First community to bureaucratic double speak this year. Your lucky they didn't give it to us in the paragraph-sub paragraph 30 layers deep form that only lawyers can write. Compared to some of the regulatory documentation and insurance policies I have received this year, The Robot rules are clearly written.