<R12> 72" x 72" Size Restriction

[BobC]

Originally Posted by Joobacca

You DO realize that 72 inches is equivalent to 6 feet. Does that answer your question?

But the question was "Where the arm might stick 4 or 5 feet outside the robot to place the top tube?"

38 inch robot plus 60 inch arm equals 98 inches which is more than 72 inches.

[Wayne Doenges]

Last year you could not extend higher than 5'. If you had a 4' 6" bot that had a door on top that was 1' long and it rotated past the 5' limit when opening you would be penalized.
This year I see a 72" L x 72" W x infinite high box and if you extend out of this box you will be penalized. Even if it's only for a moment.
Just my $.02 YMMV

[ttedrow]

Originally Posted by BobC

But the question was "Where the arm might stick 4 or 5 feet outside the robot to place the top tube?"

38 inch robot plus 60 inch arm equals 98 inches which is more than 72 inches.

R12 is very clear. They define a "Box" 72"x72" of which the diagonal is more than 101"
But, if the arm swings out of the box, you risk being panelized. I don't know if this will be an inspection item this year. The sizing is already complicated with the different classes. The Refs may have a way of measuring on the field.

Try designing a round robot using omni wheels. It will be very hard to define the width and depth axis.

[Kingofl337]

I guess the big problem is with and arm while its lifting a ringer from the ground robot will normaly break that 72" plane for a brief amount of time and then return to within the 72" rule. To stay within the rule your arm would have to retract the arm back in towards the robot before extending out again. I think the intention of the rule is to stop huge robots roaming around the field and not to limit arm design. But, thats question I'm trying to find out.

[Brandon Holley]

I honestly cannot wait to see the refs out there with tape measures trying to see what the invisble 72" box is, and when a robot extends out of it. Honestly this seems quite difficult to enforce if what were talking about is the correct interpretation.

[Richard Wallace]

Originally Posted by Brandon Holley

I honestly cannot wait to see the refs out there with tape measures trying to see what the invisble 72" box is, and when a robot extends out of it. Honestly this seems quite difficult to enforce if what were talking about is the correct interpretation.

I can seen Robot Inspectors doing exactly that, before your robot ever gets to the field. An extra long arm is a potential safety hazard to people near the field boundary, such as referees, emcees, announcers, field resetters, etc. To protect those people, the Lead Robot Inspector has discretion under <R112> to keep any robot off the field, even for practice, until it has been brought into compliance with the rules.

[Brandon Holley]

Originally Posted by Richard

I can seen Robot Inspectors doing exactly that, before your robot ever gets to the field. An extra long arm is a potential safety hazard to people near the field boundary, such as referees, emcees, announcers, field resetters, etc. To protect those people, the Lead Robot Inspector has discretion under <R112> to keep any robot off the field, even for practice, until it has been brought into compliance with the rules.

I also can see this, but there are many different orientations of robots. This also severely limits the types of arms you can make, articulation will require some thorough calculations.

[Taylor]

The rules are simple. Your robot may, during normal play, not exceed 72" X 72". Use your GP, stay within the confines of the rules, don't try to bend or break these rules and everything will be fine. Yes, some rules make the game hard - that's the point! With each limitation comes a new challenge, another opportunity to show off your team's ingenuity.
Personally, I would hope that refs would never have to whip out their 72-inch measuring sticks - if the robots are designed respectfully within the given boundaries, there won't be any problems.

[Kevin Sevcik]

Originally Posted by boiler

The rules are simple. Your robot may, during normal play, not exceed 72" X 72". Use your GP, stay within the confines of the rules, don't try to bend or break these rules and everything will be fine. Yes, some rules make the game hard - that's the point! With each limitation comes a new challenge, another opportunity to show off your team's ingenuity.
Personally, I would hope that refs would never have to whip out their 72-inch measuring sticks - if the robots are designed respectfully within the given boundaries, there won't be any problems.

Again, my only question is if it's a 72"x72" box you have to fit in, or if you paste something on your robot that says "72" this way, and 72" that way."

[Richard Wallace]

Originally Posted by Kevin Sevcik

Again, my only question is if it's a 72"x72" box you have to fit in, or if you paste something on your robot that says "72" this way, and 72" that way."

I expect the inpsection checklist will have a line item corresponding to <R12>. The test will probably be to place the arm or extension so that it is at its maximum reach, then verify that the robot still fits within the 72" wide x 72" deep limit. Of course, passing this test will not ensure that an arm is legal. Safety is always the paramount concern, and <R03> clearly says that an otherwise-legal device on a robot can be disallowed if, in the judgement of the inpsectors or referees, it poses a hazard.

[Brandon Holley]

i think this rule is good, arms could get out of control...but then again this is FIRST :-P

[Richard Wallace]

Originally Posted by Brandon Holley

i think this rule is good, arms could get out of control...but then again this is FIRST :-P

Uhh, yeah. I was one of numerous volunteers to get inadvertently whacked by a tetra in 2005, while standing near the edge of the field. I recall seeing video somewhere of another volunteer actually getting capped, and something similar happened to a robot operator when an arm reached over the end wall and dropped one.

FIRST will continue searching for rules and procedures to keep us from hurting ourselves. However, none of this will substitute for judicious application of common sense.

[Brandon Holley]

Originally Posted by Richard

FIRST will continue searching for rules and procedures to keep us from hurting ourselves. However, none of this will substitute for judicious application of common sense.

without a doubt

[Kevin Sevcik]

Originally Posted by Richard

I expect the inpsection checklist will have a line item corresponding to <R12>. The test will probably be to place the arm or extension so that it is at its maximum reach, then verify that the robot still fits within the 72" wide x 72" deep limit. Of course, passing this test will not ensure that an arm is legal. Safety is always the paramount concern, and <R03> clearly says that an otherwise-legal device on a robot can be disallowed if, in the judgement of the inpsectors or referees, it poses a hazard.

I would surmise as much, but I'm going to ask the question anyways. I've seen enough official interpretations counter to my instincts that I feel safer just checking.

[Pat Fairbank]

Originally Posted by Richard

The test will probably be to place the arm or extension so that it is at its maximum reach, then verify that the robot still fits within the 72" wide x 72" deep limit.

I don't think this kind of test would work. The rule states that "a ROBOT may expand up to a maximum width of 72 inches and depth of 72 inches", not that the robot must fit within such a limit at maximum extension.

If a team were to design a robot with an arm that was mechanically capable of exceeding the limit, but either programatically limited the horizontal extension of the arm or trained their operators to always stay within the limit, it wouldn't appear to be a violation of <R12>.