Re: YMTC: Redabot weighs 129.8?
 

I have mixed feelings on this. I agree that the weight you play at is the weight you should weigh in at, but I think the spirit of this year's rule was to put a cap on possible configurations, rather than leaving virtually unlimited potential function. Modular design is an increasingly popular trend, and I believe the rules this year were designed to prevent any one team from essentially building multiple robots. I think it's cool to see a robot with a modular arm which can alternate from ball manipulation to hanging, based on strategy. However, a robot with a standard base and multiple toppings (say, two small ball handlers, a 2x ball grabber, and a hanger) all as separate "functions" is a bit over the top. While technologically cool, in the legal sense each topping could be considered a different robot with different functions. The spirit of this year's ruling was to prevent this. All configurations must be weighed together to total no more than 130lbs.

To answer the original question, by the letter of the law, and from my experience as an inspector, I'd have to rule the second motor illegal if it tops the 130 pound limit. The rules clearly state the robot must not weigh more than 130lbs in ALL possible configurations, even if it's just one more motor. Otherwise, robots could be nickel and dimed up to more weight- if you can add an extra motor on the alternate configuration why not add another motor to another function if it's only a little over the limit.

Regarding the spare part issue- a spare part must be identical in form and function to the original part it would potentially replace. If it has different properties or different functions, it's not a spare, and would have to weigh in as an alternate configuration, which by this past season's rules, would have to be weighed in as part of the whole robot.

Re: YMTC: Redabot weighs 129.8?
 

Tristan,
I would say it does not pass inspection since it is a not fully assembled attachment. It is not in the form at which it will compete and therefore cannot be weighed until complete. As an inspector I would ask that assy be finished and weighed or the team decide to leave the attachment in the pit and not use it during competition.

Re: YMTC: Redabot weighs 129.8?
 

Al are you saying that if the 2nd assembly does not have a motor attached then it is not a functioning piece so that it cannot be used. I do not see a problem with the motor being used on both assemblies as long as it is transfered. If you weighed the robot after changing the motors there would be no weight difference. I am not sure of that part of the rule, if there is one, so could you
help me out a bit with this.

Re: YMTC: Redabot weighs 129.8?
 

Steve,
The intent is to have all assemblies and basic robot that are used for competition weigh in less than 130. If one of the assemblies is incomplete it is not in the form which will compete. If the motor used for both attachments, were part of the basic robot then it would pass. I know that sounds a little contradictory, but the team did/could have had that chance. Moving a motor from one assembly to another to make weight does not fit into the rules in my opinion.
As a team that has competed with attachments in the past, the change in rules in 2004 made a change in our design strategy.
I need to add here that the 130 lb. weight limit is one which allows two (athletic) students and/or adults to get the robot on the field and I support that. Additional attachments that make a robot more than 130 is pushing the envelope of safe handling and I must be against that.

Re: YMTC: Redabot weighs 129.8?
 

In understand the 130 lb weight limit. I agree that 2003 had a better rule. I also saw robots weighed in with all extra parts even though they were not complete. My belief, which is not law, was that the total weight of all pieces would weigh in at 130. In the above case there is only one motor being used. does it matter which assembly it is on. The team must remove it from one and use it on the other so it is really not a set on either assembly. In Tristan's case there are 2 motors involved which is wrong.

Re: YMTC: Redabot weighs 129.8?
 

Steve,
There were robots that weighed in with unassembled attachments. Those teams in most cases were not sure whether they were going to use the attachments or not. We told those teams that officially, if they made changes in the completed assemblies they were required to weigh in a second or third time to insure all competition parts were weighed in total. To my knowledge the teams complied with that request. There is a point that GP must enter into the game and I fully expect participants to reweigh when changes are made. Teams expect that their alliance partners and opponents are legal to compete.

Re: YMTC: Redabot weighs 129.8?
 

At the UTC regional the inspectors performed "spot checks" on random robots on their way out of a match. The weight/size stations were setup relatively close to the field access ramp, so throughout the day Friday and Saturday, robots were periodically "pulled over" for an on the spot weight check. This essentially prevented mechanisms from being added or modified without re-weighing, as on the way out from a match, it's difficult to remove anything added from before the match.

Re: YMTC: Redabot weighs 129.8?
 

Marc gets it, exactly. His understanding of both the specific wording and intent of the rules is correct. I respectfully suggest everyone read his message thoroughly.

As defined in the original problem statement, Redabot is illegal and in violation of the weight constraint.

-dave

Re: YMTC: Redabot weighs 129.8?
 

This is one of the downfalls of the 2004 rule. The spot inspections cannot account for the other mechanisms and their weight. The spot inspection would not find that redabot is illegal as the team would most likely not be carrying both arms with them.

Re: YMTC: Redabot weighs 129.8?
 

Well, Redabot would have had to weigh in with all possible configurations together to pass the inspection initially. The spot checks were intended to stop anyone from "pulling a fast one" and using modified/uninspected configurations post-inspection. Without the spot checks, nothing (legally, not ethically) would stop them from adding whatever to the bot to put it over 130lbs, even after passing the only required inspection.

Re: YMTC: Redabot weighs 129.8?
 

Marc or Dave. The question I have is, would the second arm be allowed if it was weighed in with no motor attached? The team would be moving the motor from the first arm to the second to compete. I understand and agree with the other posts. Al stated that the robot could not be weighed in with out a second motor. If you could state the rule for this I would really be thankful because I was unable to find after looking for and hour.

I love good discussions. They make the brain cells work overtime. :)

Re: YMTC: Redabot weighs 129.8?
 

The rules do provide for other teams to alert FIRST officials is something seems wrong, keeping GP in mind and no sour grapes and all. So I think it's more that without spot checks, a team would be operating illegally until caught or something. Obviously all inspections are required events, a team can't just say they don't want to be reinspected. Anyways, I believe Lone Star had a policy of giving each team a cursory reinspection during Eliminations, and a bit more stringent inspection during Finals. However, our Chief Inspector is a bit crazy. :)

Re: YMTC: Redabot weighs 129.8?
 

The key point in my reasoning is Natchez's stipulation that "only one mechanism is on Redabot at a time" (i.e. a situation where both were attached would be physically impossible). It wouldn't be a "possible configuration" of the robot to have both modules installed. (In the situation where both modules might be attached at once, the rule is unambiguous.)

The fact that a drill motor is a common part to both assemblies means that it shouldn't matter in which position a drill is installed. I would suggest that Al's statement that it is not a "fully assembled attachment" is an ad hoc ruling, and one that is not explicitly stated in, or even supported by the official rules. While it may be a reasonable ruling, it is not the only possible interpretation of the rules as written. For the purposes of inspection, I would expect that the robot have only one drill motor attached, and therefore would come in underweight.

For the purposes of having your assembly ready for competition, the later installation of the second motor is equivalent to switching the drill for a fresh one while you change assemblies, unless, of course, FIRST was really trying to disallow the time savings involved. I don't see how that could be construed as a sensible motivation.

To further clarify my position, consider the following: you have a device which can accept an M12, 50 mm bolt in any of 24 positions. Only one M12 bolt is to be installed at a time, during competition. By the same sort of reasoning which requires a team to install both drill motors for weigh-in, the team is also required to install 24 M12 bolts, because a provision for attaching such a component exists. I'm reasonably sure that nobody would have insisted upon this absurd situation, even if it would have resulted in an overweight robot; but perhaps because of the "high profile" of the drill motor, we're granting it special treatment in this regard.

Re: YMTC: Redabot weighs 129.8?
 

Slippery slope arguments are... well... slippery. Judging extremes is never a good bet, because it's easy to come up with absurd examples for anything. Viz.:

The Fighting Dumples have two possible bolt-on assemblies for their robot, constructed of extruded aluminum, and highly engineered cardboard boxes. Brilliantly, these two assemblies use almost all the same motors and pieces of aluminum and sprockets, just arranged in a highly different fashion. The base robot weighs 60 lbs. Assembly A's unique parts weigh 15 lbs, and Assembly B's unique parts weigh 15 lbs. The common parts between these two add-on assemblies weigh 40 lbs. So the robot makes the weight limit, and presumably the size limits. Sadly, because of the ingenuity and large reuse of parts, it takes 1.5 hours to disassemble A and reassemble it into B and vice versa. By your logic, since all the common parts are already there, the Dumples can have a perfectly legal and fully assembled A and B structure ready to go, since the common parts are "spares". Thus, the Dumples are saved 1.5 hours of frenetic building and can easily swap structures before a match.

While silly, this example is just as valid, and seems just as wrong. I think the point of the "fully functional" assembly argument is to prevent any and all weird interpretations like this from coming up. The point of mandating that the same drill motor be swapped, or that the motions atleast be made, is that there is obviously a secondary cost incurred to make this weight savings. Namely, however much time you need to move a drill motor.

We have been instructed to read the rules with a common sense sort of interpretation, and not be lawyerly. I believe the intent and purpose of this rule is to allow teams to be creative and use exchangable modules while limiting the possibility of Swiss-Army bots with several attachments suitable for any strategy. If teams will insist on an utterly clear, highly detailed rule here, then the solution becomes to pick between creativity and no Swiss-Army bots. The alternate configuration rule is a relatively recent addition, so I'd be cautious about pushing one's luck.

Re: YMTC: Redabot weighs 129.8?
 

It is most definitely a slippery slope situation. I wish that we could figure out rules that didn't lend themselves to that sort of argument, because Kevin, or I, or anyone else, can pick out a situation that makes the rule look foolish. Doing so isn't being "lawyerly", though--it's an easy way of gauging what could go wrong with the rule, and in so doing, it guides your personal interpretation of what's reasonable. When we're asked to consider "gracious professionalism", or the "spirit of FIRST", we're interpreting the rule--whether it does or doesn't happen to coincide with the unspoken beliefs of the rule-writers is irrelevant, because by leaving ambiguity, and leaving room for interpretation, the door is open to a wide variety of reasonably considered, and strictly legal variations, even though some extreme cases might not be terribly appealing. For that reason, you need a rule to define the limits of what's acceptable, not merely the fallacious argument "it isn't graciously professional enough".

So while I think that Al's "fully functional" stipulation is quite sensible, I don't think that there is enough basis in the rules to force a team to abide by it; they couldn't reasonably be expected to have inferred that from what the rules stated.

In real life, we do have laws that are ill-written, and we do have people who argue about semantics, and people who push the limits of what's acceptable. If we want FIRST's rules to represent a broad cross-section of what's good and bad about law and its conventional interpretation in society, then loopholes are par for the course. Otherwise, we need to actively strive to be explicit about our rules. The trick is controlling interpretation, without limiting creativity.