Re: Octave Capability / Control Mach3 System

[Przemek Klosowski]

On 06/30/2010 04:38 AM, Rian Lauwrens wrote:

> I am a 2nd year Mechanical Engineering student busy with vacation work
> at the NMISA. I am designing a system consisting out of a Mach3
> breakout board, Geckodrive stepper driver, Stepper Motor and a linear
> actuator. I want to write an Octave program to control the whole
> system via the Mach3 controller through a parallel port.
>
> I would appreciate it if someone could answer the following questions for me:
>
> Will I be able to do this with Octave or will I need to use MatLab?
> Do I need to download some sort of driver to control the Mach3 or will
> I have to write it?
> Is it true that I will send the Mach3 the GCode from my Octave program
> to move according to my specifications?

I happen to know a little bit about this. You write that you use the 
Mach3 breakout board, but you also imply that you are planning to use 
the Mach3 software. Mach3 is a CNC system---numerical control of a 
material machining station. Essentially, it receives Gcode (RS274) 
commands for configuring a machine (lathe, mill, plotter, etc), 
calculates the trajectories of the elements of the machine (X,Y,Z axis, 
tool spindle, etc), and issues commands to the actuators (stepper 
motors, linear actuators, etc). The utility of Mach3 is in calculating 
those trajectories to take into account constraints like acceleration 
limits in multi-axis moves, cutting speeds, imperfections like backslash 
and difference between climb and conventional cutting. It also knows how 
to interface to many motor controllers, like your Gecko.

Normally, Mach3 takes Gcode files as input, and interprets them to move 
the machine. I don't know whether and how can Mach3 take realtime 
command stream.

Are you sure you need Mach3 at all, rather than directly driving your 
actuator? If you do need it, consider instead using the Free machining 
software called EMC2, http://linuxcnc.org/ . For instance, I do know 
that EMC2 has a Gecko driver, and it has a provision for streaming live 
commands into it via the emcrsh, 
http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Emcrsh