axis control vs numerical control

  • Thread starter SILVESTRI Marco - Computes
  • Start date
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Thread Starter

SILVESTRI Marco - Computes

Hi to everybody!

I'd want to know your opinions about choosing a board in order to control a 3 axis machine.
Which are advantages and disadvantages of choosing an axis control or a numerical control?

Thanks in advance.

Best Regards

Marco Silvestri
 
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Brandon Ellis

Marco:

What is the difference? I am not being facetious, but in actuality, a multi axis motion controller and a numerical controller function the same. The difference traditionally is that the NC is programmed primarily with G Code. This is now possible with alot of multi axis controllers today. Please keep in mind that when I say multi-axis controller, I speak of only those capable of the CNC application. In other words, if the application requires only 2-D with an electronically geared third axis (Z axis for example), then there are quite a few
controllers available to do this very well; however, if your application requires true 3-D capability, including 3-D cubic splines, and
consisting of 6 or so axes, then there is but one multi-axis motion controller I put my confidence in, and that is Delta Tau.

Feel free to contact me via email or telephone to further discuss this should you have any further questions.

Regards,


Brandon S. Ellis
Sales Manager
Robotic Control Group
700 S. Illinois Ave.
Suite A104
Oak Ridge, TN 37830
Tel: (865) 425-0301, Ext. 160
Fax: (865) 425-0268
http://www.roboticcontrol.com
 
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SILVESTRI Marco - Computes

Well, I don't know what are G-codes, so I suppose I need them...

Regards

Marco Silvestri
 
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Brandon Ellis

Marco:

G-Code is simply a programming language used primarily for the machining industry. With the use of G code, a semi-standard CNC programming
language was established - that is until custom G Codes began to flourish, leaving only the fundamental commands as standard.

Whether you need G code or not is entirely up to you. If you don't know (and don't want to know) G code, then you have plenty of other options.
These other options, however, whether graphical or not, usually end up translating the program into G Code. Thus, another difference between a
multi-axis controller and a NC controller (remember, they are the same in operating principle), most NC termed (or CNC) controllers out there are built around G code programming, the motion controller, however, it designed such that it will accept its own language or the G code
language (sometimes a G Code to "controller" language converter is required).

I hope this explanation helps,

Brandon S. Ellis
Sales Manager
Robotic Control Group
700 S. Illinois Ave.
Suite A104
Oak Ridge, TN 37830
Tel: (865) 425-0301, Ext. 160
Fax: (865) 425-0268
http://www.roboticcontrol.com
 
If you're not using G codes there are a lot more options available to you... but then you're probably not using what most people call CNC. Precision MicroControl Corp www.pmccorp.com, Galil, Acroloop and MEI all make these
controllers in addition to Delta Tau.

Bob Close
Executive V.P.
Precision MicroControl Corp
TELE 760-930-0101
FAX 760-930-0222
[email protected]
 
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There seems to be some confusion about G codes.
G codes are part of the EIA RS-274D standard for the part programming of machine tools.
Part programming is different from the programming that an application engineer does
to interface a controller with a machine. Part programming is the way you enter information into the controller/machine combination in order to
produce the particular part that needs to be machined.
If you are an application engineer interfacing a motion controller to a machine, you will not use RS-274D with its G and M codes. You will use
whatever the vendor offers. Many motion controllers have their own special language. Such is the case with Delta Tau and Galil. Many others use variations of ladder diagrams. Allen-Bradley has GML which is an ICON type language plus they have a ladder version, too.
Many engineers feel that a STATE language is best because it follows the flow of the machine actions.
Control Technology Corporation out of Hopkinton, MA is probably the most established leader in this category.
I guess what I'm telling you is to select a vendor and not a language.
Tom
Thomas B. Bullock, President
Bull's Eye Marketing, Inc.
Industrial Controls Consulting Div.
E-mail: [email protected]
Phone 920: 929-6544
 
C
The key difference is in the level of integration and flexibility. Numerical controllers (NCs, or CNCs) tend to be highly integrated and less flexible; "axis controllers" less integrated and more flexible.

If you use a CNC, you are getting a whole global approach to the problem -- basically the approach of a milling machine. This includes G-codes for motion programming, ladder logic for I/O programming, and a machinist's operator interface. If you can accept this straitjacket, it's a good approach, because a lot of the work has already been done for you.

If you need more flexibility, you are probably better off with a general-purpose multi-axis controller (full disclosure: my company produces these; others have been mentioned as well in this thread). You have some more work to do to tailor these general-purpose boards to your specific purpose, but you get a lot more flexibility in the bargain.

Curt Wilson
Delta Tau Data Systems
 
Marco:is there an online manual for macro programming? I use a three axis machining centre and mill/turn lathe with conventional g-code programming.
 
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