RE: [CAD_CAM_EDM_DRO] Re: Interface. Gauging interest.

Sheesh - haven't thought about Forth in a long long time...

It still has quite an active interest group:
http://www.forth.org/

It was designed by Chuck Moore to do the motion control at the US
National Radio Astronomy Observatory in the early 1970s, and has been
used by some organizations for animation and motion control (Disney was
a big user).

It has advantages in that it is fully extensible -- if there is a
command that you want that isn't supported, you can write the code to do
it and Forth will self-compile the new command into your copy of the
language.

The syntax is RPN -- Reverse Polish Notation (the larger HP calculators
use this).

I am imagining that this would probably be a bear to support
commercially as every system would be slightly different with people's
own extensions and hardware differences. It is very small and very fast
but really best for one-off applications.

Thanks for the memories -- used to work with it on some lab control
systems.
Dave

> -----Original Message-----
> From: CAD_CAM_EDM_DRO@yahoogroups.com
> [mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Mike Pogue
> Sent: Monday, May 15, 2006 11:13 PM
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Subject: Re: [CAD_CAM_EDM_DRO] Re: Interface. Gauging interest.
>
>
> I've been thinking about this.... There's a language that
> was built for
> exactly this kind of machine control thing: Forth. It's tiny,
> extensible, and fast. It's mature. It's designed for machine control.
>
> But, the world operates on g-code nowadays, so it's not clear
> to me that
> a language switch makes sense at this point in time. Here's why -- a
> new language could certainly be done (fairly easily), but
> would anybody
> use it? You and I would, but how about all the other vendors
> out there?
> It would require new drivers (post processors) for CAM
> software. And,
> new training for 1000's of operators.
>
> So, the benefits of a new language (whatever syntax you choose) would
> have to be large/compelling, to overcome the disadvantages, I think.
>
> Mike
>
> Jack Hudler wrote:
> > 1) That's what I thought.
> > 2) Hear! Hear! This is what freaks me out about using the
> parallel port; I would
> > not want my Domain Server backing up my CNC machines to
> wreck my machine.
> > 3) Hexapod? Answer is; you wouldn't. The Hexapod would
> appear as a 3 axis
> > device, or more depending on what end effecter you attach.
> >
> > To follow up on the G-Code part of the third point; there
> needs to be another
> > language created for Modern CNC. Professionally I am a
> Windows programmer; I've
> > played around with a CNC program that is driven via
> scripts. The scripts can be
> > in any language the Windows scripting host supports.
> Currently VBScript,
> > JavaScript, Python, PerlScript, RubyScript, TclScript, and
> ForthScript are but a
> > few of the supported languages. Of course you'd have to
> reduce this to the
> > lowest common denominator for *nix.
> > Right now my stuff doesn't understand G-Code, I just
> program the part in and run
> > the script.
> > Example: CNC.Home(0,-1); // means home X
> axis rapid (G0)
> > CNC.Home(1,-1); // means home Y
> axis rapid (G0)
> > CNC.Home(2,-1); // means home Z
> axis rapid (G0)
> > CNC.WaitForOperator("Ready to start making chips");
> > CNC.Spindle(0,1000,0); // Main Spindle (0)
> spin up 1000 rpm, CW
> > CNC.FeedRate(2,2.0); // Z Axis feedrate 2 IPM
>
> > {
> > // Create a 3D fractal
> > // write your favorite Mandelbrot or
> Julia set here.
> > // Or if your not into 3D than a simple
> Koch Curve.
> > //
> http://www.jracademy.com/~jtucek/math/dimen.html
> > // Show me this in G-Code.
> > }
> > // See where I'm going?
> >
> > Think of this new language like HTML and CSS, you just
> define a new keyword, or
> > similar to embedding scripts in a web page. You give them
> names and call them.
> > I am not proposing getting rid of G-Code just be allowed to
> augment it in a
> > standard way without having to modify the interpreter.
> >
> > I have seen one case on a diamond turning machine where the
> finish pass on an
> > beryllium mirror takes over 40 hours (non stop) to
> complete. I can't imagine
> > G-Code could ever handle such a numerically complex task
> (paraboloids of all
> > types, or interlaced paraboloids). Nor would I trust it.
> However, the machine is
> > not as versatile as it could be because everything must be
> described in software
> > to machine a surface where nanometers make the difference
> (floating point
> > rounding errors taking off a few extra atoms on that radii
> or less on the next,
> > looks like phonograph record when done, and not acceptable).
> >
> >
> >
> > -----Original Message-----
> > From: CAD_CAM_EDM_DRO@yahoogroups.com
> [mailto:CAD_CAM_EDM_DRO@yahoogroups.com]
> > On Behalf Of Mariss Freimanis
> > Sent: Monday, May 15, 2006 8:09 PM
> > To: CAD_CAM_EDM_DRO@yahoogroups.com
> > Subject: [CAD_CAM_EDM_DRO] Re: Interface. Gauging interest.
> >
> > Couple of additional points:
> >
> > 1) I wish the G-Rex was a pizza you cut into 6 slices and take as
> > many as you need, 1 slice or all 6.:-)
> >
> > It doesn't work that way; a single axis still needs the Rabbit
> > RCM3720, the Xilinx FPGA, the FT245BM USB controller, the
> regulators,
> > connector blocks, xtal oscillators, pcb, enclosure, LEDs, etc, etc.
> > All you would save for a "single slice" would be a few
> 74HCT 10-penny
> > parts.
> >
> > 2) Step pulse generation is donkey-work a PC shouldn't have
> to do. It
> > is singularly ill-equipped for that task. This properly belongs in
> > dedicated hardware like an FPGA; it was born to do that.
> >
> > Off-loading this onerous task from the PC relieves its
> burden. Art of
> > Mach fame reported he could watch a DVD and surf the web
> while Mach4
> > was running a complex contouring program. This on a slow PC
> without a
> > burp.
> >
> > PCs are meant to compute, not to do bean-counter accounting parsing
> > out microsecond step pulse timing and counting. It is the
> latter task
> > that makes PCs difficult to run easily no matter the OS.
> >
> > 3) G-code is at best a 2-1/2 axis control code. It is unimaginably
> > unweildly for higher axis counts. How would you efficiently write
> > application code for 6-axis of coordinated motion like a hexapod
> > using g-code?
> >
> > Mariss
> >
> >
> >
> >
> >
> > Addresses:
> > FAQ: http://www.ktmarketing.com/faq.html
> > FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
> > Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com
> >
> > Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> > Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> > List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com,
> wanliker@..., timg@...
> > Moderator: pentam@... indigo_red@...
> davemucha@... [Moderators]
> > URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
> >
> > OFF Topic POSTS: General Machining
> > If you wish to post on unlimited OT subjects goto:
> aol://5863:126/rec.crafts.metalworking or go thru Google.com
> to reach it if you have trouble.
> > http://www.metalworking.com/news_servers.html
> >
> > http://groups.yahoo.com/group/jobshophomeshop I consider
> this to be a sister site to the CCED group, as many of the
> same members are there, for OT subjects, that are not allowed
> on the CCED list.
> >
> > NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY
> POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO
> EXCEPTIONS........
> > bill
> > List Mom
> > List Owner
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
>
>
>
> Addresses:
> FAQ: http://www.ktmarketing.com/faq.html
> FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/
> Post Messages: CAD_CAM_EDM_DRO@yahoogroups.com
>
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com,
> wanliker@..., timg@...
> Moderator: pentam@... indigo_red@...
> davemucha@... [Moderators]
> URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
>
> OFF Topic POSTS: General Machining
> If you wish to post on unlimited OT subjects goto:
> aol://5863:126/rec.crafts.metalworking or go thru Google.com
> to reach it if you have trouble.
> http://www.metalworking.com/news_servers.html
>

http://groups.yahoo.com/group/jobshophomeshop I consider this to be a
sister site to the CCED group, as many of the same members are there,
for OT subjects, that are not allowed on the CCED list.

NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM.
DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........
bill
List Mom
List Owner


Yahoo! Groups Links