Interesting/Cool Scaling Mechanism Designs

[GeeTwo]

Originally Posted by Dave McLaughlin

I was told while spectating 4060 at Auburn on Saturday that they fill the tube using a fan, separating it from the pneumatic system. I believe they 3D printed many of the components.

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

[JABot67]

Originally Posted by GeeTwo

If you're doing work with air, it's a pneumatic device.

If this is true, then all fans and fan-blown vacuum devices on FRC robots are illegal.

It is unclear to me what constitutes a pneumatic device. Obviously nothing custom can be connected to the "canonical" pneumatic system on the robot, which is heavily regulated.

EDIT: Vacuums are legal per R77. Other things maybe not.

R79 Compressed air on the ROBOT must be provided by one and only one compressor. Compressor
specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC.

Hard to argue that an inflatable tube hanger does not create compressed air.

[bennettj800]

so how does a 3d printed fan fill a cheapo innertube to extend...?
could this be the work of a secondary compressor? (it may very well be the same work of the one original with a solenoid allowing for a tank to empty into it... or something... :/

also, i dont know that its the most consistent way to hook onto the bar, seeing as it wobbles here and there when they do it...

(again, please let me know if i have the wrong thought train here...)

(like, please... pretty please)

[Cory]

Originally Posted by GeeTwo

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

I love the confidence with which you make your clearly wrong statement.

[Navid Shafa]

Originally Posted by Cory

I love the confidence with which you make your clearly wrong statement.

I guess we may never know the answer to the age old question:

How much SWAG is too much SWAG?

[orangemoore]

Originally Posted by GeeTwo

It looks like that homebrew compressor was pushing a whole lot more than 1.1 cfm. If you're doing work with air, it's a pneumatic device. (Noted exception for closed cycle air springs.)

Custom Airblowers created from legal motors and fan parts are not constrained by the Pneumatic rules.

If you don't believe me please point to the rule(s) that prove what you are saying.

[bennettj800]

Rule R79:
"Compressed air on the ROBOT must be provided by one and only one compressor. Compressor specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC."

this has already been pointed out...

also, a custom fan blowing a tube up (like a balloon) would be, in any circumstance, a compressor, thereby violating this rule. ergo, the custom fan has got to go if it is actuating something like it is.

[martin417]

Originally Posted by bennettj800

Rule R79:
"Compressed air on the ROBOT must be provided by one and only one compressor. Compressor specifications must not exceed nominal 1.10 cfm flow rate @ 12VDC."

this has already been pointed out...

also, a custom fan blowing a tube up (like a balloon) would be, in any circumstance, a compressor, thereby violating this rule. ergo, the custom fan has got to go if it is actuating something like it is.

For the purpose of FRC, a compressor is a positive displacement device.

Fans are legal per R29:

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

A fan is a fan, not a compressor. The rule does NOT say "a fan is legal unless you blow it into a tube", so don't try to create rules that don't exist,

[GeeTwo]

Originally Posted by martin417

For the purpose of FRC, a compressor is a positive displacement device.

What about:

Originally Posted by martin417

don't try to create rules that don't exist

FRC doesn't define a compressor but they do say that there shall be only one source of compressed air, and that it must be rated 1.10cfm or less. I don't remember anything about a positive displacement device in the rules...

[martin417]

Originally Posted by GeeTwo

What about:



FRC doesn't define a compressor but they do say that there shall be only one source of compressed air, and that it must be rated 1.10cfm or less. I don't remember anything about a positive displacement device in the rules...

Note: the below is my opinion. I am not on the GDC. For a definitive ruling, submit a question to the GDC.

A fan does not provide compressed air, it provides flow. That is why it is very difficult to even find a rating for delta P for most muffin fans as supplied in the KOP in the past. But I was able to find a rating for for a special "high static pressure" muffin fan for restrictive computer cases. This "high static pressure" fan was able to create a static delta P of .002 PSI when dead-headed.

Fans are listed in the rules under the electrical rules, not the pneumatic rules, for the excellent reason that they are not pneumatic devices.

The Q&A cited earlier was a question about using air from a solenoid valve attached to the pneumatic system, not a fan.

If you are not a member of the GDC, do not cite your opinion as fact (note that I have taken my own advice).

[GeeTwo]

Until and unless the GDC clarifies otherwise, I'll continue to assume that the manuals are written in American English.

[martin417]

Originally Posted by GeeTwo

Until and unless the GDC clarifies otherwise, I'll continue to assume that the manuals are written in American English.

Can't really argue with that. Of course it really has no bearing on the productive discussion at hand. My admonishment stands: If you are not on the GDC, please do not state your opinion as fact.

Are my bumpers compressors? When my robot is in motion, there is a rise in static pressure across the surface. What about closed cell foam (like pool noodles are made of)? when force is applied to the foam, the pressure inside the cells of the foam is increased. Every time two robots collide or push against each other they are creating air pressure inside the closed cell foam far in excess of anything that could be produced by a muffin fan.

The pneumatic system rules are very clear. Fans are not mentioned, in English or any other language.

[Chris is me]

Originally Posted by GeeTwo

Until and unless the GDC clarifies otherwise, I'll continue to assume that the manuals are written in American English.

What are you even talking about? Like, honestly, this post makes absolutely no sense. No one said anything about what language to read the manual in, or the definitions of words.

The Manual allows fans, both electronics muffin fans and fans powered by FRC motors. A cloth bag placed over a fan is not containing compressed air - it's just containing air. The bag restricts flow of the air somewhat but it is not airtight - the bag does not stay even close to inflated the second the air is cut.

These rules have been the same for years, and in previous years the GDC has explicitly allowed mechanisms just like these. There's substantial historical precedent for these mechanisms (see blockers in 2013, similar hanging mechanisms in 2010, etc). You can't state your opinion as certain fact and then refuse to listen to anyone else's view unless the GDC says so. You're applying different levels of scrutiny to yourself versus others.

[bkahl]

Originally Posted by GeeTwo

Until and unless the GDC clarifies otherwise, I'll continue to assume that the manuals are written in American English.

Do the Canadians get this in Canadian English?

What about those Aussies?

And we can't forget the Hawaiians!

------------------------------------------------------------------------

Seriously Gus, your logic just isn't there.
From my understanding...
If my dump valve happens to dump air into a Versatube somewhere on my robot because its mounted near that, I guess that's part of the pnuematics system now?

Introducing the new VEX Versatube with new PNEUMATIC Features!

What about the 2013 blocker I remember 116 having at IRI?

[Lil' Lavery]

Originally Posted by bkahl

What about the 2013 blocker I remember 116 having at IRI?

To be fair, I wouldn't make the assumption that a device added specifically for an off-season event that doesn't have an inspection process is legal.