Legality of third party fans

[cantdecide]

R29 says:

Hard drive motors or fans that are: included in any Kickoff Kit, distributed via FIRST Choice, part
of a legal motor controller (including manufacturer provided accessories), or part of a legal COTS
computing device

We recently bought a number of 40mm computer fans to mount on our Talon SR ESCs, but this rule caught my eye. Since we didn't obtain the fans via a kickoff kit or via FIRST Choice, and they're not the original fans or bought via the ESC vendor, and they're not previously included in a COTS computing device, are they legal? We're not using them strategically, just as replacements for Talon SR fans, and they're not doing anything unexpected from a fan. Just regular 40mm fans.

[MaGiC_PiKaChU]

I guess your fans don't fall into any of those categories... thus making them illegal.
I can't imagine your robot would not pass inspection because your cooling fans are third party tough.

[cantdecide]

Originally Posted by MaGiC_PiKaChU

I can't imagine your robot would not pass inspection because your cooling fans are third party tough.

That's exactly what I thought. They would be technically illegal, but practically not. However, I'd still not like to rely on its practical legality, so I'm a bit over the fence on whether we should use them.

[MaGiC_PiKaChU]

Originally Posted by cantdecide

That's exactly what I thought. They would be technically illegal, but practically not. However, I'd still not like to rely on its practical legality, so I'm a bit over the fence on whether we should use them.

if they are sold as a computer fan, I guess it would fall in the intent of the rule...
I recommend you ask on the Q&A

[GeeTwo]

Originally Posted by MaGiC_PiKaChU

if they are sold as a computer fan, I guess it would fall in the intent of the rule...
I recommend you ask on the Q&A

On the other hand, I see this as outside the intent of the rule. The rule is intended to be very specific. Only fans that are part of a KoP or FIRST Choice or sold specifically for an allowed motor controller are allowed, with the exception that a fan included on a COTS laptop (or other COTS computing device) does not render the COTS computing device illegal.

[rich2202]

Originally Posted by cantdecide

just as replacements for Talon SR fans

If it looks like a duck, and quacks like a duck, it must be a duck.

If it doesn't look like a duck, then you've got some 'splainin to do.

That said, your RI may not look closely enough to see if it looks like a duck vs a goose.

[D_Price]

I definitely would not try to bypass the rules in anyways. If your RI would happen to "glance" at more than just the frame of the robot then you would still be in violation of the rules.

Originally Posted by MaGiC_PiKaChU

I guess your fans don't fall into any of those categories... thus making them illegal.
I can't imagine your robot would not pass inspection because your cooling fans are third party tough.

[Joe Johnson]

I read this rule to be that any Victor Fans (e.g. the model of fan that comes with a Victor 888) are legal regardless of whether they were acquired via purchasing a Victor or whether they are being USED ON THE ROBOT to cool a Victor.

I think if you started to take the impellers off and use the motors to do work beyond blowing air, we might have something to talk about but I think as it is as long as you are using the same model fan as any of the fans listed, you can use them in unlimited numbers.

That's how I read it anyway...

Dr. Joe J.

[Sparky3D]

This rule bothers me. DC powered "computer" fans are pretty ubiquitous, using a different brand/model isn't going to give you a competitive advantage. On top of that, it's borderline unenforceable. Does the GDC really expect all inspectors to have a list of every year's KOP and try to match model numbers on every fan that shows up on a robot?

Sorry for the rant, but it would make things so much easier if the rule were something along the lines of "DC powered computer fans of size X or smaller are legal". Easier and cheaper for teams who need to cool a compressor/motor, and much easier for inspectors to enforce.

[Jon Stratis]

Originally Posted by Sparky3D

This rule bothers me. DC powered "computer" fans are pretty ubiquitous, using a different brand/model isn't going to give you a competitive advantage. On top of that, it's borderline unenforceable. Does the GDC really expect all inspectors to have a list of every year's KOP and try to match model numbers on every fan that shows up on a robot?

Sorry for the rant, but it would make things so much easier if the rule were something along the lines of "DC powered computer fans of size X or smaller are legal". Easier and cheaper for teams who need to cool a compressor/motor, and much easier for inspectors to enforce.

Having built a few computers in my day, I know that not all fans are created equal. There are some out there that get much more airflow than others, despite being the same size. So the rule does have some practical applicability.

That said, when inspecting the robot, I'm not going to be closely examining every fan that's attached to a speed controller. If it looks like one of the fans that's stacked up in my team's electrical closet, then I'm going to assume it's legal. If it's a some blue one with built in LED's, then I know it's not legal (and yes, they sell ones like that, for people who want "cool" looking Computer cases!). If your using the fans to do something other than cooling on motor controllers, I'm going to take a closer look at them.

[Sparky3D]

Originally Posted by Jon Stratis

That said, when inspecting the robot, I'm not going to be closely examining every fan that's attached to a speed controller. If it looks like one of the fans that's stacked up in my team's electrical closet, then I'm going to assume it's legal.

This is exactly my point. If an experienced LRI's method of enforcement is " it looks like one of the fans that's stacked up in my team's electrical closet", what is an average inspector's(aka me) method of enforcement supposed to be?

Originally Posted by Jon Stratis

Having built a few computers in my day, I know that not all fans are created equal. There are some out there that get much more airflow than others, despite being the same size. So the rule does have some practical applicability.

I completely understand, but my point is "Does it matter?". Even a high powered 120mm computer fan doesn't provide enough thrust to launch a boulder or deflect a frisbee. Are there safety concerns with using "some blue fan with LED's"? Is using a high powered fan an unfair advantage to some teams? I'm just trying to understand why we have the restriction to KOP fans in the first place.

[engunneer]

I'd say they aren't legal. CTR doesn't sell them, and they don't meet any of the other criteria for legality. If they happen to have the same model number as the one Andymark sells as part of first choice, I'd pass them. Otherwise, I'd bring it to my LRI.

In general, I think the fan limitations were designed to keep the playing field level on power. If you had super awesome fans on your air compressor or speed controller, you could get more power through them, therefore giving a competitive advantage.

[Rosiebotboss]

Originally Posted by Sparky3D

I completely understand, but my point is "Does it matter?". Even a high powered 120mm computer fan doesn't provide enough thrust to launch a boulder or deflect a frisbee. Are there safety concerns with using "some blue fan with LED's"? Is using a high powered fan an unfair advantage to some teams? I'm just trying to understand why we have the restriction to KOP fans in the first place.

The important point here is this: "Does it matter?" Probably not.

Is it legal? No.

Your call. Do you want to potentially miss a match?

[ratdude747]

Originally Posted by Rosiebotboss

The important point here is this: "Does it matter?" Probably not.

Is it legal? No.

Your call. Do you want to potentially miss a match?

Yeah. As asinine as it is, the rules are the rules.

It would be nice for next year though, maybe at least have a size and/or airflow/current restriction. Some of the higher end (read, not for PCs or even workstations/servers) brushless fans run so fast that they'll rip off fingertips ... and unless you had grilles or the fans actively controlled (to only be on in Auto/Teleop), which could also mandated in the rules, such fans wouldn't be safe for robots that often get carried while booting up.

---

That said, the fans are still fine for off-season use... before the modern battery rules (which are like what I described above, only for batteries), there was only one (and later two) batteries one could use. Up to 2006 it was Exide (IIRC, I wasn't in FIRST that far back), then 2007-2009 it was MK only, with Enersys batteries becoming the new KOP brand in 2010 as a second legal choice along side the MK units. What teams would do is use the "legal" batteries for competition and use those and other batteries of the same specifications for everything else. At least in my old team's (1747) case, we had a local electronics supply for a sponsor and they carried PowerSonic batteries, of which an equivalent was available.

The same could be done with the fans, as the rules only apply at competition. In fact, if you have legal fans on talons already that aren't going to see competition use (in an old/demo bot or the like), I'd swap them, which would save the cost of buying new legal fans. Sure they'd be used, but that way the fans wouldn't be sitting without a use.

[SamM]

We're having trouble finding info on fans from previous KOPs.

Does anyone have a manufacturer/model number list of what was given in previous KOPs?

Were 80mm fans given in any of them?

Thanks!