Ethical dilemma? You decide.

[Cory]

This rule isn't even worth worrying about.

What are the odds you'll want to use what you already did in it's EXACT configuration? Not very high, most likely. You'll probably want to change the distance between wheels, the exact position of the gearbox in the tubes, the mounting points for motors, provisions for tensioners, etc.

We have a family of parts that has not changed in two years and isn't likely to change again this year. We have machine code for our CNC mill to make each of the three parts that theoretically could be used from two years ago but every year it becomes more obvious that the previous year's code, while workable, needs to be optimized to lessen run time, lower tool wear, increase accuracy, etc and never actually stays the same.

I would argue that all you would have to do is delete all your selected geometry from your toolpaths, go back in an hour after kickoff, reselect the geometry and you've satisfied the rule about previous design. You wouldn't even need to delete all of it, but then you have another question of how substantial do changes have to be for it to be "different". Can you delete a toolpath to drill one hole and then redo it and call it different?

[BJC]

A lot of teams walk this fine line every year. Many of them are very respected and well-known teams, all have very respectable people on them, and none of whom I would consider to be "cheaters". No matter what is said in this thread, however, it is ultimately your decision what to do. My Advice: Do what would make your grandmother proud.

Sincerely, Bryan Culver

[Tristan Lall]

Strictly speaking, isn't the CNC program the design of the process used to create the robot part, rather than necessarily an element of the design of the part itself? I grant that the design of the part and the design of the CNC program might certainly be codependent, but fundamentally, they're separate things. Completion of one does not necessarily imply completion of the other—it would be quite reasonable to contend that the design of the part depends on the lessons learned from the implementation of the CNC program, and that the "final design" of the part is incomplete until the results of a trial run are analyzed and deemed satisfactory.

And although FIRST hasn't said so explicitly, I give serious credence to the idea that the robot rules must be assumed to only apply to actual parts of the robot, unless otherwise specified. (If you read the LabView example as applying to non-robot code, it opens up a world of unenforceable insanity.)

Put another way, logically, if you were to instantiate the part design, you'd get the part. But if you instantiate the CNC program, you get a machine following a toolpath—and maybe a part as well, but only if you decided to cut metal (or whatever the part is made of) rather than thin air.

And in any event, like Chris and Cory said: if you're still uncomfortable, make any one tiny geometric change, and it's unambiguously no longer the same part. (The old part can rightly be called a prototype, if you happened to make any. Don't use the prototypes in competition.)

Following my own chain of reasoning, I disagree that posting it publicly would be a remedy under the rules—stuff that isn't part of the robot has no particular reason to be (or to become) COTS.

Aside: See here....

[Al Skierkiewicz]

Example: The same TEAM realizes that the transmission designed and built in the fall perfectly fits their need for a transmission to drive the ROBOT arm. They build an exact copy of the transmission from the original design plans, and bolt it to the ROBOT. This would be prohibited, as the transmission – although fabricated during the competition season – was built from detailed designs developed prior to kick-off.

This would seem to say it all in your case, substituting "code" for "plans". As Cory has said, a little examination of the CNC code will show that some improvements can be made in the code. You can move things around, make more efficient use of programming space, etc. The skills are already there, this could be a great opportunity for your students to practice and learn.