Re: 5-axis machine controller

[Jon Elson <jmelson-at-artsci.wustl.edu>]

john s finnila wrote:

> I am starting a project to add a 5-axis simultaneous servo control to an
> existing  om-3 milling machine.   The milling machine has existing dc
> servo motors with conventional
> plus or minus ten volt dc servo amplifiers and tach generated velocity
> feedback.  I plan
> on using quadrature  output  encoders for position feedback.  I am
> planning on doing this
> control retrofit using the emc controller.   I have successfully
> completed one control of a 3 axis milling machine complete with
> automatic tool changer using a packaged pc-based control runnning under
> dos.  This gives me a little background.  I would very much
> appreciate any and all advice  from  anyone  on the nist  mailing list
> concerning this project.

Well, I've only done 3 axes.  You will have to modify the kinematics
routines to include the correct geometric computations for your
specific arrangment of linear and rotary axes.  There are some robot
kinematics routines that could be useful in understanding how to
define this.

Otherwise, it is a pretty straightforward job, and almost anything you
need to change can be done in the .ini file.

I was probably the first person to set up a servo system on my own,
other than the developers at NIST.  If you have trouble with servo
tuning, I can be of assistance.

Since EMC is open, there is nothing that you can't change, but you may
need to study the code for a bit to understand how it works, first.

Jon