As some of you might now I am heavy into 3DP and see great use for it for FRC. I am retired and love designing and would like to make my designs available to all in an FRC legal/make sense (COTS?) way.
So the draw back for 3DP parts is that they generally are not a COTS but a Fabricated item and with that have to be discarded at the end of each season (discarded from FRC use). Except if lets say andymark prints them for you and anyone in which case they are COTS (seems cause some business made money on it).
So there are online printing services. If I either
a.) set up a storefront where everyone can order the 3DP parts within the 5 days etc. Now the online printing service is a VENDOR (if it can ship within 5 days and most can in some cases you might have to pay extra for “rush service” like for example shapeways.
b.) just publicly upload the stls and sell them for a penny or whatever. It seems FRC does not allow things to be given away for free and be COTS. At least as how I read the rules as if there was a free way I do it - or could it be “sold” for a voluntary donation. I design the stuff for teams to use and not to make a living.
Now the part of the rules are a bit murky to me when it comes to the “equivalent” part. So question is if the item is available from and online print service for $xxx and with that COTS. would it still be COTS if you print it yourself from the exact same STL in exact the same way/material etc etc. Or would it become a fabricated item that only has a life cycle of one year as no “vendor” profited of it.
My goal is to make my parts available to anyone who wants to use them as a contribution to robotics. At least intellectually - as I don’t have the resources to supply all of FRC for free lol. And even if I did - the way I read the COTS - I would give them away and you would not buy them and hence the core of COTS (vendors getting $$$) would be eliminated.
So is there a way to not turn all prior years 3DP stuff into trash at kickoff day. Or do what some teams I know of do with lets say 3DP pulleys - they say “I have no way of telling if that pulley was printed this season or survived the purge from a prior season - besides we want to be environmentally conscious”
This seems like a rule that really should be changed to allow reuse of 3d printed parts more easily. For example, I have a number of the 120A Breaker Shield’s that AndyMark provides the STL file for. I printed them off so I can provide them to teams at events if they need them - and I’ve provided quite a few over the years. Never even thought twice about it, but when I have extra at the end of the season, they just go in the crate I bring to competition and get mixed in with new prints the following year to be provided to teams as needed. In that sort of situation, there’s no competitive or vendor-related reason to disallow those parts, although the rules as written don’t allow them. I’d love to figure out exactly what changes are needed to the rules to allow these sorts of parts.
I think the rules are like they are to make their donors $$$ as the emphasis seems to be on “off the shelf” sold with emphasis on “sold”. As you mention andymark the funniest things are things like the “String pot” initially designed by an FRC team then shared and then sold by andymark. Now if you buy it from them 3D printed its COTS. if you download the STL and print it yourself its not COTS so the difference is “Did andymark make a profit?”
For the string pot example, would it fall under R302 E, being functionally equivalent to a COTS part? It creates a difference between something like the String Pot and the 120A Breaker Shield - one is a 3D printed equivalent to a COTS part, the other is not available as a COTS part.
As I understand it, the rule is there as an attempt at enforcing parity. If a part can be re-used each year then it needs to be available to every team. This prevents a high resource team from having a large collection of custom parts they can simply grab off the shelf at any time. It definitely has some very bad unintended consequences, though, and I personally hate the forced waste.
Just so we are clear, we are mainly discussing R302:
R302 *Custom parts, generally from this year only. FABRICATED ITEMS created before Kickoff are not permitted.
Exceptions are:
A. OPERATOR CONSOLE,
B. BUMPERS,
C. battery assemblies as described in R103-B,
D. FABRICATED ITEMS consisting of 1 COTS electrical device (e.g. a motor or motor
controller) and attached COMPONENTS associated with any of the following
modifications:
a. wires modified to facilitate connection to a ROBOT (including removal of existing
connectors),
b. connectors and any materials to secure and insulate those connectors added (note:
passive PCBs such as those used to adapt motor terminals to connectors are
considered connectors),
c. motor shafts modified and/or gears, pulleys, or sprockets added, and
d. motors modified with a filtering capacitor as described in the blue box below R625.
E. COTS items, or functional equivalents, with any of the following modifications:
a. non-functional decoration or labeling,
b. assembly of COTS items per manufacturer specs, unless the result constitutes a
MAJOR MECHANISM as defined in I101, and
c. work that could be reasonably accomplished in fewer than 30 minutes with the use
of handheld tools (e.g. drilling a small number of holes in a COTS part).
While we seemingly benefit from it, AndyMark is not pushing for these rules, and I love exception E-c that was added in the last few years permitting the use of modified COTS parts.
On a personal rules lawyering note, one of my printers has a handle on it, does that make it a hand tool like the drill mentioned in the example? Now since I believe 3D printer filament is a COTS item, does that mean that anything I can print in 30 minutes or less would fall under exemption E-c?
you have the “need to publicly share” rule if you want to reuse a design (not the par) and its easier for a high resource team to do that. They can easier afford to throw stuff away and reprint/remachine it at the beginning of the season than a low resource team. Lets assume you made a custom shooter that cost you 500 bucks and next year or in 2 years you need the same - a high resource team easily builds the same $500 “custom” shooter whereas a low resource team might struggle to come up with the $500 again where a perfectly fine one is sitting on the shelf. The only one who would loose out are the ones making a profit selling shooters
It would be great if FIRST would just consider striking R302. I’m not sure who it helps in practice, and anecdotally it seems to create a lot more frustrations than provide benefits.
Yeah I mention Andymark a lot as it comes to mind as the vendor I am most familiar with as you have been the #1 supplier in my case for now 12 years.
Now i got handle on a printer too and easily could put one on all of mine. As for the 30 min do you count printing time or actual work time as most of the time I just start a print which takes minutes and then go do something else. Now if you want to make my parts “legal” by selling them - lets talk I got a ton
Maybe they need to come under rules like software/code does. That is, you publicly post code so that anyone can use it, which makes it reusable by you as well. The same could be done for 3DP parts. If you publish it or if it is a publicly available .stl file, then it’s allowed to reuse it even if you printed it in a previous season. It would allow teams to reuse common things (like your breaker shields or spacers) and thus reduce waste, while still keeping unusual or highly specific parts within the realm of other non-COTS parts, since they’d be specific to the season and robot and thus not really the things teams would reuse in any case. Just seems like that would be a viable fix to the problem and would also allow individuals like @mpirringer and teams to put the neat and generally useful things they come up with out there for everyone to use, in the proper spirit of coopertition, just as we do now with robot code.
I feel like it should be similar to code with a few tweaks, given the CAD is open and public, the parts list or where to find needed parts is included, and basic manufacturing instructions are provided I don’t see a reason why it would be unfair to allow parts to be rolled over year to year, disallowing rollover stifles things like innovation in custom swerve modules where teams need months just to design them and can’t afford to refabricate them every season which is just driving most teams to only use COTS swerve.
I think the issue there would be that everyone uses the same Roborio, but 3DP can be far more variable. Just because I give you CAD for a part for my (hypothetical) metal 3D printer doesn’t mean you’ll be able to make it. The same would apply for other materials beyond PLA. You could even see issues with PLA if someone has a particularly large printer bed (or belt printer) and can creat large parts that many people won’t be able to recreate.
Maybe restrictions that the part being reused must be PLA and must fit on a certain relatively small bed size.
Is there an official process to request rule changes, I know team 900 pushed hard for some reform on multi device CAN control I’m wondering if there would be a way to collect enough teams and common consensus to put forwards an official request for the rule change.
But that’s the thing, not everyone issues it, Rio 1 to Rio 2 is a huge difference and there are now more then 10 common coprocessors some teams like 900 don’t even use the first libraries in most of their code using ROS instead now.
I’m fairly certain this is one of a handful of rules designed more to appease the audience (specifically sponsors).
Explicitly allowing teams to reuse major mechanism or entire robots, which would have been extremely advantageous for a few games, would probably not jive well with sponsors, or at least First seems to think that.
The reality is that it’s a non-issue, but the perception of the possible perception seems to be bad, if that makes sense.
I can think of a few games where a relatively poor team would do a erage by reusing a robot, but exceptionally few where it would be competitive compared to making one from mostly-scratch.
Even if 2020 robots could shoot 2022 balls, it’s not like 254 was about to sit back and re-use their old robot. Same goes for 99% of competitive teams.
The rule overwhelmingly benefits teams that can afford to rebuild each year and hurts those who cannot, plain and simple.
As far as I can tell, this would make the parts bought from Shapeways COTSCommercial, off-the-shelf and it would allow identical parts printed by teams before the season to be used during the season, since they would be “functional equivalents” of COTSCommercial, off-the-shelf parts. If you also uploaded the STLs, you wouldn’t even have make any Shapeways sales for teams to print your parts before the season and use them during the season.
This would not be sufficient. Custom fabricated parts must be made during the season, even if their designs are available before hand.
Regarding PLA - well its not that suitable for robotics except for some minor brackets its pretty useless. Its brittle and it deforms easy if it gets too warm and its abrasive with itself so if you use it for gears it generally grinds itself down quickly. HIPS, ABS, PETG and maybe Nylon (expensive) are much better. And pretty much any newer printer can print it.
Regarding size… as for my parts… Its true I have a 400x400 printer and have done some big parts but probably around 90% of what I design can be printed on an Ender 3. I got one of those too (I bought a pro for $100 on sale) And all except maybe a few can be printed on a 300x300 like a CR10 or similar. All new parts I print at least one on an Ender 3 to make sure most anyone could do so. And yes I upgraded my Ender 3 to all metal ($11 bimetal heatbreak) or other printers to a volcano clone ($25ish) and my ender now has direct drive (orbiter). All in all even getting a new cobra max (400x400x450) is less than $500 and then you could also buy the parts.
Regarding - accuracy… I got 4 printers (Currently 3 working) and they all can print the same parts - even planetaries - interchangeably. They can be tuned quite easily to be accurate enough. The only exception maybe is that for example on my big printer I got a .8 nozzle and that (unless I change it) limits how small I can print (so HTD5 is ok GT2 not so much that needs a nozzle <.6)
So it would come down to learning how to print accurate with your printer kinda like its necessary to learn how to use a drill press or any other tool properly
