Fixtures for FRC

[Tyler2517]

I know it is illegal to use none off the shelf components that you built before kickoff. Is it illegal to use pre-built fixtures for machining on cnc/manual equipment? I cant decide if it would be or not i fell like its a weird grey area...

[Knufire]

Standard caveat: Chief Delphi isn't an official source of rule interpretations. Past rules may not be future rules.


ROBOT elements created before Kickoff are not permitted. ROBOT elements, including software, that are designed
before Kickoff are not permitted.
Exceptions include the following:
A. BUMPERS,
B. OPERATOR CONSOLE,
C. battery assemblies per R5-A, and
D. software and designs with source files publicly available prior to Kickoff.



ROBOT: an electromechanical assembly built by an FRC Team to perform specific tasks when competing in AERIAL
ASSIST. It includes all of the basic systems required to be an active participant in the game: power, communications,
control, mobility, and actuation. The implementation must obviously follow a design approach intended to play AERIAL
ASSIST (e.g. a box of unassembled parts placed on the FIELD or a ROBOT designed to play a different game would
not satisfy this definition).


By that definition, I wouldn't consider fixtures to be part of the ROBOT, and therefore not fall under the restrictions specified by R13.

[Tyler2517]

I guess to use fixtures you would need pre designed parts and such... You could make fixtures that hold generic parts then change final sizing for the game.

[asid61]

That would be pretty unfair IMO. Does that mean custom lathe stops have to be rebuit every year? It seems like a big inconvenience to smaller teams.

[Mike Marandola]

I guess to use fixtures you would need pre designed parts and such... You could make fixtures that hold generic parts then change final sizing for the game.

If they are generic, just make the designs public and you can use them.

[EricH]

I would consider such fixtures to be similar to blueprints. In the past, blueprints have been considered to be part of the design--but if you happen to post them publicly, they're fair game to be used.

So if you were to put your design out, and then note that "oh, by the way, we found the following fixtures very helpful to have, here's the design and approximate fit points", I don't think anybody at all would have a problem.

If a rule has a blue box, that can very often be very helpful in understanding what the intent/violations of the rules are.

[cgmv123]

The 2014 rules do not consider parts/structures used to create FABRICATED ITEMS to be FABRICATED ITEMS themselves and thus parts/structures used to create FABRICATED ITEMS are not subject to 2014 R13.

[Tyler2517]

I know we have 2 fixtures that made machining our swerve really easy last year; pain in the butt to build but well worth the time to rebuild if necessary type of things.

I graduated but would be a nice thing to hand down.
I know any thing said on chief delphi is not official.
The designs were released before the end of last build season so that's not a problem...

[Orion.DeYoe]

I know it is illegal to use none off the shelf components that you built before kickoff. Is it illegal to use pre-built fixtures for machining on cnc/manual equipment? I cant decide if it would be or not i fell like its a weird grey area...

I think there are two kinds of fixtures we could be talking about here:

1) A fixture designed for a specific part. It is not useful for any other part. e.g. a plate used for locating cuts on tubing for an arm used in the 2014 game.

2) A fixture used for making repeated feature spanning multiple robots. It can be used in a variety of ways. e.g. a block with a locating pin and drill bushings to drill a straight pattern of 1/4" holes 1" apart.

Type 1 is VERY closely related to CAD drawings and designs in general. I wouldn't push that limit if I were you. Type 2 I think is fully in keeping with the rules.

Note: If you're not sure about it, post the design on CD, and then you can use it during the build season because it has been made equally available to all teams.

[Tyler2517]

I think there are two kinds of fixtures we could be talking about here:

1) A fixture designed for a specific part. It is not useful for any other part. e.g. a plate used for locating cuts on tubing for an arm used in the 2014 game.

2) A fixture used for making repeated feature spanning multiple robots. It can be used in a variety of ways. e.g. a block with a locating pin and drill bushings to drill a straight pattern of 1/4" holes 1" apart.

Type 1 is VERY closely related to CAD drawings and designs in general. I wouldn't push that limit if I were you. Type 2 I think is fully in keeping with the rules.

Note: If you're not sure about it, post the design on CD, and then you can use it during the build season because it has been made equally available to all teams.

I am talking about a #1 here something designed and built to only ever build relevant in making that one part or something very very close to the original parts design.

[EricH]

I am talking about a #1 here something designed and built to only ever build relevant in making that one part or something very very close to the original parts design.

And I would assume that if you're building that part, you'll need said #1-type fixture, or some near equivalent. (Logical continuation)


If I wanted to play it safe, which I suspect you do, I would release some form of documentation--blueprint, CAD, etc.--along with the part that it goes to. WHERE you release it is up to you--CD is one option; FRC Designs might take it; you could just put it up on your team's website.

[Tyler2517]

We don't need it to make it and the parts i am talking about have been published else where forever ago thank you.

[Mr V]

My interpretation is that posting designs for something like a fixture would not allow you to reuse the fabricated fixture, use the design to build a new fixture yes.

[Mike Marandola]

My interpretation is that posting designs for something like a fixture would not allow you to reuse the fabricated fixture, use the design to build a new fixture yes.

But the fixture wouldn't be part of the robot. The posted design would be of the part created using the fixture.

[Tyler2517]

But the fixture wouldn't be part of the robot. The posted design would be of the parted created using the fixture.

Its a grey area i fell like its in the letter of the law but not the spirit.

[dtengineering]

"Robot elements that are designed before kickoff are not permitted." (unless the design is published prior to kickoff)

The fixture is not an issue here. It won't be on your robot, so it is not subject to the robot rules.

The key aspect is the design. If the design of the part occurred before kickoff then you either need to publish the design in advance, or else go through the design process all over.

Note, however, that while you have to re-design the part... you can use your off-season experience and experiments to streamline the design process.

And yeah... that is a pretty grey area. I'd say just publish your design, build your fixture and then proceed with a clear conscience. Just remember that the Game Design Committee has been known to throw the occasional monkey wrench in to the work to ensure that no one ever gets too confident about their ability to use a pre-season design.

Again... the issue is not the fixture... it is the design.

Jason

[asid61]

We don't need it to make it and the parts i am talking about have been published else where forever ago thank you.

Where were they published, out of curiosity?

Anyway, reflecting more on this topic, I think that you should have to release the design for it or for the part it is making. This is because it would be used in a manner like a blueprint would be, to make something. It's not a huge things to ask that teams release their fixtures for parts.

The spirit of the law is what matters here. It's more a of a question for Q&A.

[Mike Marandola]

Its a grey area i fell like its in the letter of the law but not the spirit.

I don't understand how it could be a grey area.

[Tyler2517]

I had manufactured them last build season and was trying to figure out if the team could use the same fixtures to manufacture the newer swerve drive. The old swerve drive was published way bad when i can go find the file.(that is what the fixture was originally for)

If the team builds another swerve this year (i dont know if they will tell build season) and i know they have some changes they would want to make but as long as its close egnuff to the original the fixture will still work.

There will be changes to it no mater what post build season so the designs being re published is not a problem.

[AdamHeard]

Fixtures are fair game in that FIRST didn't mention them.

They also are merely a tool/process... common sense here.

There is no issue here, nothing needs to be disclosed or posted.

[dtengineering]

Fixtures are fair game in that FIRST didn't mention them.

They also are merely a tool/process... common sense here.

There is no issue here, nothing needs to be disclosed or posted.

I agree with you regarding the fixtures... however if the fixtures are specific to one design and are built prior to build, then that implies (requires!) that the design of the part was completed prior to build season. Since that part will be on the robot, it is covered by the design rules.

It isn't whether the fixture is built before build season, but rather whether the part was designed before build season.

Jason

[Al Skierkiewicz]

Jason has hit the answer in both of his posts I think. The fixture in general is not part of the robot so realistically, robot rules do not apply. However, the chicken and egg conundrum does apply here in that the design of the part made easy by the fixture, came before the season starts.
I am still awed by teams who dedicate themselves to a design before the game is announced. I have stated this many times before, we do not use crab drive if the game doesn't benefit from it's use. We won't know until the game is announced ( a few short weeks away) and the team has had a chance to analyze how to play the game effectively.