Re: [CAD_CAM_EDM_DRO] EMC Following Error

Bill,

thanks for the quick reply. I reduced the velocity to 0.5" per sec and also
lowered the acceleration to 1.0. This runs without the following errors. I
will experiment to see how much I can increase these values.

I had already made some pulley blanks so that I could reduce the 32000 steps
per inch to 16000. This afternoon I cut the teeth on them. I hope this will
allow me to increase the speed somewhat within the limits of the motors.

You asked about the computer speed - 700 MHz. What sort of step rate can I
expect to achieve?

Regards,

Dave.

David Micklethwaite

> David
>
> Following errors while running steppermod means the computer can't put out
> the steps as fast as you are asking it to, and you're are asking quite a

bit

> of the
> computer by trying to output 32,000 steps per inch at 1.2 inches per

second.

> Since you can't do much about the steps per inch at this point, you can

try

> to lower your max acceleration to somewhere around 5 and the default
> acceleration to about 3. If this fixes the problem, you can up the numbers
> a bit and try again until the problem comes back. If that does not work

try

> lowering the max velocity. Even if you get this to work well when doing
> straight jogs, running a program with circular interpolation in it will
> probably
> cause lots of following errors. What speed computer are you running?
>
> Probably your best bet is to get the number of steps per inch down to a

more

> reasonable level either by changing the belts and pulleys or ask Mariss of
> Gecko Drive if you can plug the step multipliers onto the G320's and make
> them into G340's. Set them for 10X and drop your input scale to 3,200

steps

> per inch. I think they are about $25.00 each.
>
> Of course others may have different or better answers.
>
> Bill
>
>
> > I am trying to get EMC working with a small mill. I have Gecko G320
> drivers
> > and am using steppermod. I can jog the axes back and forwards by the
> amounts
> > I expect and in the right directions. However, I occasionally get
> following
> > errors and do not understand why.
> >
> > The emc.ini parameters that I think are relevant are:
> > TASK = minimilltask
> >
> > ; Trajectory Planner
> > section --------------------------------------------------
> > EMCMOT = steppermod.o
> > DEFAULT_VELOCITY = 0.0167
> > MAX_VELOCITY = 1.2
> > DEFAULT_ACCELERATION = 20.0
> > MAX_ACCELERATION = 20.0
> >
> > ; Axes
> > sections ---------------------------------------------------------------
> > ; First axis
> > [AXIS_0]
> >
> > TYPE = LINEAR
> > UNITS = 0.03937007874016
> > HOME = 0.000
> > MAX_VELOCITY = 1.2
> >
> > INPUT_SCALE = -32000 0
> > OUTPUT_SCALE = 1.000 0.000
> >
> > FERROR = 1.000
> > MIN_FERROR = 0.010
> >
> > I have other questions about the emc.ini file but I'm happier taking one
> > step at a time!
> >
> > Regards,
> >
> > Dave.
> >
> > David Micklethwaite
> >
> >
> >
>
>
>
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