Re: Windows timing subroutines, how do they work? JitteryMonkey pic

Sorry, was a broken link.

http://home.alltel.net/dec4857/jitterymonkey.jpg
http://home.alltel.net/dec4857/jitterymonkey1.jpg

My page..
http://home.alltel.net/dec4857/index.htm

You can tell I don't access them pages often..
David






--- In CAD_CAM_EDM_DRO@yahoogroups.com, "ibewgypsie" <ibewgypsie@h...>
wrote:

> Howdy Mariss..
>
> Are ya after my heart and mind? I'll check it out. If you don't know
> me, I love new toys.. Anything to make my machine better, quicker,
> stronger, shinier.. (I bolted some polished stainless to it)
>
> I found your Jittery Monkey..
> http://home.alltel.net\dec4857\jitterymonkey.jpg
> http://home.alltel.net\dec4857\jitterymonkey1.jpg
>
> My page..
> http://home.alltel.net\dec4857\index.htm
>
> David
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mariss Freimanis"
> <mariss92705@y...> wrote:
> > David,
> >
> > Has happened already. Conventional constant contouring techniques
> > use "look-ahead" schemes and complex math to move at a constant
> > velocity along a concatened line segment path.
> >
> > The G101 uses a velocity-word stream to the step pulse engine. This
> > allows for a unique and very simple constant contouring method I
> > call "look-behind". Simply put, the generated velocity-words (along
> > the concatenated path, no accel/decel) are passed thru a moving
> > average filter whose output goes to the pulse engine.
> >
> > Some advantages over conventional techniques is this method requires
> > no analysis of the line-segment coordinate data, uses only add,
> > subtract and division by powers of 2 (bit right-shift). It natively
> > adapts to the requested vector velocity, automatically increasing the
> > rounding at line-segment nodes the faster it goes. The filter can be
> > switched in and out on the fly to allow accel/decel where sharp
> > direction changes are required.
> >
> > If you want to see it run, please see www.geckodrive.com, go to
> > the 'support' page and pick the very last item listed (video). The
> > pen in the video is tracing at 300 IPM on a 6" by 6" XY stage having
> > 5 TPI screws. The motors are 3A/phase PK268s at 24VDC. The drives are
> > G201s. It could go much faster but the screws sound very unhappy
> > above 1,500 RPM.
> >
> > The file is about 5 megabytes so having a broadband connection is a
> > real plus.
> >
> > Mariss
> >
> >
> >
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "ibewgypsie"
> > <ibewgypsie@h...> wrote:
> > > What is probably needed? One Timing generator running at a obscene
> > > speed, smaller processors that get a bluetooth into buffer dump for
> > > distance or usb, or? Each processor handles one axis, reading the
> > > encoder to adjust it's own loop-feedback, running pulse ratio per
> > main
> > > engine. All interpolated, All with a error out line back to main
> > > source to err-out. Each axis dedicated to itself. Then here-we-go..
> > > Look ahead software that processes speed changes per gcode line and
> > > pid's it all to that frequency to make desired end of line
> > directional
> > > changes without losing it's interpolation between axis. Ramp up,
> > Ramp
> > > down each line is not a good way to machine, but the only thing I
> > have
> > > saw on my machine.
> > >
> > > Will it happen, probably not.
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "caudlet" <thom@t...> wrote:
> > > > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mariss Freimanis"
> > > > <mariss92705@y...> wrote:
> > > > > In my opinion it should not be the task of a PC to do
> > the 'donkey
> > > > > work' of generating step pulses be it Linux, DOS or Windows.
> > That is
> > > > > a task that belongs to dumb dedicated hardware.
> > > > >
> > > > > A PC is an 'intelligence engine'. It's task is to do a lot of
> > math
> > > > > and make decisions. Its output product should go to a 'pulse
> > engine',
> > > > > hardware finely tuned to the task of generating of producing
> > pure and
> > > > > clean frequencies on demand from the PC.
> > > > >
> > > > > These are tasks are so diametrically opposed it's like using a
> > claw
> > > > > hammer for a screwdriver. In a pinch you can do it but it's not
> > > > > pretty.
> > > > >
> > > > > That also pretty much surmises what I have seen from most PC
> > based
> > > > > CNC programs. The step pulse phase jitter is horrible even from
> > the
> > > > > most popular out there. The motors sound like a barrel of
> > agitated
> > > > > monkeys and I have the scope pixs to prove it.
> > > > >
> > > > > If things are going to be done right, the PC has to interface
> > to some
> > > > > kind of step pulse engine.
> > > > >
> > > > > The 'agitated monkey' part. Motors that sound like that are
> > being
> > > > > robbed of their potential torque especially at high speeds.
> > Phase
> > > > > modulation imposes unnecessary torque demands (infinite
> > impulse
> > > > > functions) on the motors. Said more simply, you pay for all
> > that
> > > > > noise in performance.
> > > > >
> > > > > Mariss
> > > > >
> > > > >
> > > > The problem in the past and currently in the present, is that
> > there is
> > > > no "standard" for an external pulse generator so you end up
> > having to
> > > > buy a "system" that is composed of software and matching
> > hardware.
> > > > Your options start to dwindle and if you want/need/desire to
> > change
> > > > the software you have to throw away the entire system. It would
> > be
> > > > like every car manufacturer deciding to use non-standard tires
> > that
> > > > only they provided or each TV network broadcating in a different
> > > > format so you had to buy a set specifically for their signal
> > format.
> > > > From a pure engineering standpoint it might make sense to hand off
> > > > signal processing to another circuit like a DSP card, but it
> > needs to
> > > > have an open set of standards that ANY software company could
> > write
> > > > to. If it's going to end up as a PC perhipheral then it needs to
> > have
> > > > drivers or open standards that make it useful with different
> > > > programs. Show me a pulser card that is not single source, has
> > open
> > > > standards and is supported by multiple vendors (especially MACH)
> > and
> > > > I'll get in line to buy one.