Time to setup my lathe with 7i76e

Cool, one more step. Are you using 2.7 or master. Your code looks a bit different to mine so I suspect its 2.7.

Still on 2.7

tecno wrote:

Still on 2.7

Thats what I thought. No wonder my suggestions did not work. All I've ever used is master

Been playing around with Backlash and I have some *issues* that I can not resolve.

MDI
Commanding z axis to move -10 and back to 0, F50 and all is well (within a couple 1/1000mm) but with F500 I get overshoot with a few 1/100 of a mm on both directions.

What parameters should I change?


How do I implement ILOWPASS to following HAL for MPG?


Thankful for your advice
Cheers
Bengt

Overshoot is likely if you dont have enough acceleration headroom for the stepgen
when backlash compensation is enabled (basically the motion planner needs double
normal motions acceleration value when doing backlash compensation)

Typically you will need to set the stepgen maxaccel value to 2.5X the affected axis maximum
acceleration value to avoid issues.

Thanks for the explanation Peter, will have a go with higher values tomorrow.

I think my values are as below so 1200 should be 1800-2000, will try that.

MAX_VELOCITY = 300
MAX_ACCELERATION = 600
# The values below should be 25% larger than MAX_VELOCITY and MAX_ACCELERATION
# If using BACKLASH compensation STEPGEN_MAXACCEL should be 100% larger.
STEPGEN_MAXVEL = 400
STEPGEN_MAXACCEL = 1200

forum.linuxcnc.org/39-pncconf/33451-time...76e?start=200#107734

How do I implement ILOWPASS for my MPG for X/Z axis?

Been trying to solve the puzzle but no go. Above HAL works but I would like to have smoother movement.

There is an example in hte docs linuxcnc.org/docs/html/examples/mpg.html

It sure does but it is only with one MPG and I have two = one for each axis.

Have been trying but I cannot get it running.