[Ground-station] How are we set for layout tools?

[Wally Ritchie]

1. Few if any tools are perfect, certainly not any PCB design tools, or as
John Ackermann eloquently put it - all of them suck to varying degrees. All
depends on whether your outlook is half-empty or half-full, what you are
trying to accomplish, and what value you place on different things -
especially, time and money.

2. Generally, we are not in the business or non-business of producing tools
- except maybe those that are so specialized to our tasks that they make
sense, either because of the nature of the task or the learning curves
associated with the alternative. So we might write some ad-hoc open-source
verification tools in python instead of an expensive simulink framework -
then again the latter may make more sense - it all depends on what we are
trying to do and the skill sets available to the project.

3. We are embarking on a level of Engineering development on a scale not
undertaken before in the Amateur community, at least with regards to the
technologies we are working with - $2000 FPA chips, $800 radio chips, 12
layer boards, SERDES lanes operating at 12GHz, multi-kilobuck dev boards.
These many technologies are pretty far from traditional Amateur radio and
hobby boards. The projects we are undertaking involve professional skill
sets in many fields. Those working in these fields are accustomed to having
tools able to do the job at hand. We are counting on many Amateur Radio
Enthusiasts who are in fact professionals with relatively current skill
sets, many with high hourly value in commercial or government settings. We
are asking such hams and non-hams to contribute to our projects on a
volunteer basis. We don't expect them to have to bring or buy their own
software tool licenses, test equipment, $3000 eval boards, or $2000 chips.
We want their skills - not their stuff. For these projects to succeed we
will find ways to supply the stuff - and the volunteers will supply the
much higher value engineering labor. Whatever investments we make in tools
will be those that are highly leveraged.

4. You wouldn't make your own hammer, or drill, or CNC machine - although
you could with open source designs. It might be fun to do that - but it
would be a diversion taking you away from the current mission. If you can
get a carpenter to build something for free labor - you wouldn't ask him to
make his own tools - just because he can. We won't build our own spectrum
analyzers or oscilloscopes - although we could. We focus on our project and
we will beg, borrow, steal, or buy if necessary the tools and test
equipment to complete the jobs we are doing.

5. With regard to PC tools, the opinions that matter are those of the
people who will be doing the critical work and what they need to perform
their job. What tools are used for a simple pi-shield don't matter much.
What tool is used to produce a 12 layer FPGA board with 5 DDR4's and a
dozen transceiver lanes may matter much - especially to the person doing
the work and the downstream fab, smt, and test processes. Over the past few
decades or so the roles of pcb layout specialist and draftsman have all but
disappeared. Mechanical engineers themselves are married to solidworks, or
Catia, or whatever. EEs are married to Allegro, Altium, OrCad or some other
multi kilobuck per seat tool - and in relatively rare cases some small
companies may use Eagle Professional multi-seat versions - some still
living in Version 7 and others having moved to Autocad Fusion. Mechanical
and Electrical groups often need close collaboration which is the value
that PCB/3dCAD integration brings to the table. Catia handled this well at
the high end if you have megabucks. Fusion looks like it's workable for the
low end. I've never known of any organization doing commercial or military
work using KiCad. I suppose it's possible but it's usually a poor choice
economically - like asking engineers to work at ping-pong tables sitting on
folding chairs with CRT monitors. These are certainly cheap and plentiful.
But productively comes from proper capitalization of workers - including
programmers and engineers. Time is money. Volunteer time may have zero
associated dollars but it has associated value that we do not wish to
squander - especially when it comes to the most complex parts of our
projects.

6. Our goals are to produce open source designs that anyone is free to
adapt to their specific needs. Some parts may require specialized tools to
use - we wish to minimize that, but non-free non-open source tools may
sometimes be required to utilize the sources. We can limit IP and
endeavor to avoid purchasing IP beyond that included with the standard
tools. But I don't think we can afford not to use commercial tools when
they are the best choice for completing a particular set of tasks. If we
need Matlab to run a vendor's filter generation tools - so be it. If
someone wants to take on converting this to Octave - please have at it. If
you can modify it and prove it's valid we'll be happy to use it. Otherwise,
we will just suck it up and use Matlab (beg'd, borrowed, stolen, or
purchased).

7. Eagle has a long following - many have used it since Version 4 or early
on Mac, Linux, and Windows. They captured a lot of users a decade ago with
free versions for hobbyist use, free versions usable by board houses, and
economic professional versions with auto-routing etc. It's a bit weird and
quirky but generally extremely stable. I don't see any reasonable argument
against using Eagle. Nor KiCad for those so inclined. But I am against
mandating either the forced use of open tools or particular tools. As
projects involving PC boards proceed - consensus will likely appear as to
what is appropriate for the task at hand.

8. While we are on the subject, PCB layout has some esoteric black art
skills - especially for RF - but a very major part of the work
load involves preparing footprints, symbols, and 3d models for parts. While
there are lots of parts in standard libraries there is a rule that says
that many of the ones you want won't be there (unless you made them
before). There is a lot of effort required to make parts correctly and to
verify them. But this does not involve special skills - just a normal skill
with the tool and the usual conventions (like what goes in what layers and
what does not. There are tools that will generate parts from generic
descriptions to the formats of popular cad tools - e.g. Ultra-librarian and
Library Loader - but they are often less than ideal - particularly with
complicated parts that should have multiple symbols in functional
groupings, not  one big block with 900 pins. Element14 also added a lot of
parts (thank you) to Eagle, but often with poor symbols. And a lot of stuff
you'll download from the Internet is poor or outright wrong. If a part
cannot be found, then considerable time will need to be devoted to building
and verifying the part before the PCB layout can continue. Even if a part
is found - is it correct? What design rules are implied? Frankly, this is
the vast majority of all PCB design activities. So this is an area where
many hands could potentially help by contributing. There will be ongoing
needs to build parts, verify parts, and manage libraries of proven good
parts. Have a look at the oresat project's Eagle libraries
https://github.com/oresat/oresat-eagle-libraries. They seem to have a
workable approach for their needs.

9. PCB design software is more than schematic capture and layout. It also
involve simulation (e.g. Spice) and design rule verification. Over the last
decade, integration with 3D mechanical tools has also become common. Those
in the tool business must  continue to provide value to their customers.
Autodesk bought Eagle to add to their other offerings. Their Fusion product
is now pretty usable and economical at the low end and integrates with
their 3D.  They continue to offer free eagle versions but their main
offering is now their $60/month Fusion product. Several in this group use
these tools professionally and they are good value for money. The Autodesk
model is pretty workable as the tools are licensed per named individual but
they can be purchased month to month (or longer). So they are a good match
to specific board projects. Part work can always be done with the free
versions or the very stable version 7. When we are designing and building
complex boards with $2000 parts a few months of Fusion for a couple of
people is in the noise. They are a wise use of funding - especially when
they leverage what would otherwise be tens of thousands of dollars of
engineering labor.

10. So I think that the original question that started this thread should
probably be rephrased as:

A. Who has available time and willingness in the coming months (and
reasonable skill) for building parts in X, or Y, or X and Z including
Footprints, Symbols (not just big squares), and 3D models and/or verifying
same keeping in mind that it's usually best for building and verifying to
be done by different persons. What tools would be needed to take advantage
of those skills.

11. As to the complex boards, I think that is going to be case by case as
design/layout/design rules etc are pretty much engineered together and
difficult to partition within a single board. Generally, the board
designer(s) will be using the tools. I'm sure expert advice on best
practices for any tool will always be encouraged and well received.

12. As a final note, Eagle/Fusion 360 in  the latest versions have a
feature called "Design Blocks" which allow grouping of components and
traces to be made and treated as one (other tools also have this but it has
been notably awkward to do this with Eagle in the past). This adds another
layer of library-like work. It's especially useful for things like
switching power supplies and audio circuits where grounding and routing
issues are critical. It's valuable to have drop in blocks for such things
that have been proven all the way to hardware verification (including EMC).
Generally using these and the 3D fetures requires Fusion as well a Fusion
user in the Organization that hosts the resources. So there might need to
be at least one more or less permanent fusion subscription by the
organization in addition to whatever month to month subscriptions are
required by those that are not already fusion subscribers.

As usual - this is only my $0.02 - your mileage may vary - use at your own
risk.

WU1Y







On Mon, Jul 27, 2020 at 3:51 PM Bruce Perens via Ground-Station
<ground-station at lists.openresearch.institute> wrote:

>
>
> On Mon, Jul 27, 2020 at 9:32 AM Robert McGwier via Ground-Station
> <ground-station at lists.openresearch.institute> wrote:
>
>> I wish to say that the issue of which tool to be used should not be
>> dependent on cost or personal ability to pay.  Don't ask me more than that,
>> but you are entitled to guess all you want.
>>
>
> This is just fine if you are making a decision on behalf of your
> university, Federated Wireless, or Hawkeye 360.
>
> We are Amateurs.
>
> It is a given that we would be using these tools in a personal capacity to
> build experience and achieve our own projects. And then using them in a
> broader role. Thus, a tool which is in our reach financially is indeed
> important.
>
> We also wish to teach with our tools. *Formal* education is not a mission
> of ORI because of the need to be licensed and accredited, and the fact that
> this would have delayed our initial 501(c)3 acceptance. But we still wish
> to teach through example, through the opportunity to participate, and all
> of the things we create.
>
> When we first got money, we used it to license proprietary software. This
> is ironic. It's certainly less than optimal, and we should be using Open
> Source if at all possible. Decisions to license proprietary products should
> never be made lightly.
>
>     Thanks
>
>     Bruce
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openresearch.institute/pipermail/ground-station-openresearch.institute/attachments/20200727/b3eed8d9/attachment-0001.html>