Re: suggestion

[Ray Henry <rehenry-at-up.net>]

Hi again Hassan.

Interesting action when you come out of estop.  There is a lot in the ini 
that I wouldn't do.  240 ipm is a bit fast for a little mill like this.  
You can change this by setting max and default velocity for units per 
second.  Your units are inches but I suspect that you have used mm for 
max and min position.

I'm not able to run with the default period here so I set it to 0.00003.  
When I start up I can see that axis 2 (z) has an interesting problem with 
motion.  Looking through that section of the ini I see

MIN_OUTPUT =    1               -63.5

Taking out the 1 allows me to get out of estop and home out each axis. 
(see note on what this does below) 

When I try to jog it goes into following error on any axis.  I changed 
the following lines to allow me to reduce jog speed.
-----from
DEFAULT_VELOCITY =	4.0
; DEFAULT_VELOCITY =	0.167
MAX_VELOCITY =          4.0

-----to
; DEFAULT_VELOCITY =	4.0
DEFAULT_VELOCITY =	0.167
MAX_VELOCITY =          4.0

With this change I am able to jog around a bit but it errors out when I 
stop jogging.  I think that it is overshooting from speed back to zero.  

I set D for each axis to 0 and tried it again.  Now I can jog around some 
without loosing it.

There are several other changes that I'd make but they were not essential 
to get it running.

DEFAULT_ACCELERATION =  2.0
MAX_ACCELERATION =      5.0

I would also set each pair of 

MIN_OUTPUT =                    -216
MAX_OUTPUT =                    216

back to 

MIN_OUTPUT =                    -10
MAX_OUTPUT =                    10

NOTE on min output and max output.  

These are designed to give a minimum and maximum voltage out for servo 
systems but they do seem to set the direction of pulses for freqmod.  
Since they were both in the same positive direction for your initial ini 
file, they act like a bias that sets the zero position of the servo loop 
outside of the possible settings.  I believe this is what causes the 
initial jerk when you come out of estop.

Hope this helps.  We would feel bad if EMC fails the ballbar tests.

Ray





On Friday 11 October 2002 03:21 pm, you wrote:
> Hi,
>
> Now these are the values on the axis
> X_axis
> INPUT_SCALE =   -4000    1.000
> OUTPUT_SCALE = -4000    1.000
>
> y_axis
> INPUT_SCALE = 4000    1.000
> OUTPUT_SCALE = 4000    1.000
>
> z_axis
> INPUT_SCALE = -4000    1.000
> OUTPUT_SCALE = -4000    1.000
>
> now as soon as i get out of the E-STOP, the z axis makes a sudden move
> 0.015 then a following error occurs.
>
> Regads
> Hassan