Re: New project...PCI based servo control board

[jmkasunich-at-ra.rockwell.com]

Jon Elson wrote:

> I have had the PPMC on the market at US $650 for the 4 axis
> setup with 16 opto-isolated digital inputs and place for 8
> SSRs to mount right on the board, so you don't need an Opto-22
> board, too.  This has 4 16-bit DACs, 4 24-bit encoder counters
> with index channel.  For $30 extra, you get differential
> receivers for the encoder inputs.  And, it has all the E-stop
> logic, with a watchdog timer, built in, too.  This has been on
> the market for over a year, and I've sold SIX units!  I haven't
> even managed to use up the run of 10 prototype boards!

> I have had the Universal Stepper Controller out for nearly a
> year (I demoed it at the last NAMES show) at $200, and Ive
> sold FIVE!  I'm basically giving these away at this price,
> at this volume.  The FPGA on this product costs $30.  But,
> it has 4 24-bit encoder counters (with index) and 4 digital
> step rate generators with 24-bit rate selection,

> So, here I have developed these products, no one wants them,
> and yet you guys are STILL arguing over what would be the
> all-time BEST CNC interface.

> All I can tell you, is unless you want to invest several
> thousand $ a MONTH into advertising, you won't sell more
> than 10 of them a year.

I can't speak for Craig or anyone else, but I don't intend to SELL
anything.  I am
well aware of how hard it is to make money selling to hobbyists.  Face it -
we're
cheapskates.

As I see it, there are two ways to build things at a profit.  One, you
build something
that you can sell in quantity, and you invest in the machinery, etc.,
needed to make
it cheap in volume.  That's basically what Gecko has done with their drives
- there's
no way they would be as cheap as they are without automation and quantity.
The
other way to make money is to build something that is customized or
otherwise
unique, and sell only to those with deep enough pockets to pay for that
unique
quality.  Jon, I think you are well aware of that approach with with your
nuclear
instrumentation.  I have done something similar selling a specialized test
jig to
tile testing labs.   Those deep pocket people are NOT the ones who build
their
own CNC machines for "fun and profit".  I just don't think it will ever be
profitable
selling CNC hardware to people like us. I'm not  even gonna try.

Whatever designs I come up with, I intend to publish as completely open
projects,
and let anyone who wants to build them do so.  If there is enough interest
to warrent
buying a batch of bare boards to get the cost down, great. If not, that's
OK too.
I'll buy one board and build my own system.  I know it will cost as much if
not more
than your $200 USC, but I certainly hope it will be under the $650 pricetag
of the
PPMC system.  (Not counting the value of my time, of course!)

If the USC had everything I want/need for my project, I might well be
buying one
instead of getting involved in this thing.  But is doesn't - I need a
couple of
additional encoder counters, and an analog output.  So being an engineer,
I'm
gonna build my own.  If someone else is doing much the same thing, then
I'll
collaborate with them.  If my needs divirge too much from what everybody
else
wants to do, then I'll go it alone again.  Regardless of how it works out,
I'll post
my schematics and code.

Because I don't expect to make any money doing this, I've been keeping the
design as simple and straightforward as I can.  I've avoided PCI like the
plague,
because I have neither the information, skills, or time to design a PCI
interface.
The single board computers I intend to use for my own project have an ISA
bus,
and I know that an ISA design is reasonable for me to do on my own.  That,
or
an EPP version, is the path I was planning.  If Craig, combined with the
guys at
opencores.org, can make a PCI version, that's great.  Perhaps I can
contribute
to the control hardware design, and others can contribute to the bus
interface...
In any case, the discussions are a good thing that everyone can benefit
from.

John Kasunich