Calling post from post (and 6 axes postprocessing)

[Edi Filipovic]

Hi,

 

Can please someone give me a Little help about way to solve 6 axes posting. 
I´we concluded that I should build a postprocessor that will run 3 subpostprocessors.

Why do I want that ?
Maybe I´m wrong and someone has other idea ?
So, first I would build 3 posts that would process different kinematics :

1) X,Y,Z,A,B

2) X,Y,Z,A,C

3) X,Y,Z,B,C

Then, the "main postprocesor" would have logic to detect which post would be used for particular operation and call particular "subpost".

And then, while posting, we would have something like this :

OP1 -> post 2)

OP2 -> post 3)
OP3 -> post 2)

OP4 -> post 1)

.... etc. .... all together would go to one joint .NC file

 

So, can I do something like that ?

Is there a function that can call another post from post ?

 

Thanks all,

Edi.

[Colin Gilchrist]

Technically, it is probably possible. That is a ton of work to do something like that though. Is this just for choosing which 5 Axis kinematic logic you want to use? If so, it is probably much easier to modify the Generic Fanuc 5X Mill Post to change the internal variables.

 

The Generic Fanuc 5X Mill Post already has the logic inside to change the kinematic configuration, rotary limits, and so on. So if you manipulate the 'mtype' variable and associated 'rotaxis' and 'rotdir' configurations programmatically, then you've got much less work to do.

[Edi Filipovic]

Technically, it is probably possible. That is a ton of work to do something like that though. Is this just for choosing which 5 Axis kinematic logic you want to use? If so, it is probably much easier to modify the Generic Fanuc 5X Mill Post to change the internal variables.

 

The Generic Fanuc 5X Mill Post already has the logic inside to change the kinematic configuration, rotary limits, and so on. So if you manipulate the 'mtype' variable and associated 'rotaxis' and 'rotdir' configurations programmatically, then you've got much less work to do.

Thanks Colin.

Well, my task now is to write a post for 6 axis mill, and I´we never done that before. I´m just looking the way to do it.

Of course, so far I´we done 5 axis posts, and that is standard in MC with good resources to start from (generic 5x posts).

At the moment I have zero resources (like some generic post as an idea how to start) or anything.

Luckily I have some time to do it, right now it´s more like "can you do it" than "when will you finish it".

I´d be gratefull for some guidance.

 

Edi

 

[EX-wccprogrammer]

If you are going to start from scratch, you will want to start with a 'positioning' post.  The matrix has all of the data to position any number of axes that your machine has.  As you change Tool Planes in Mastercam, the matrix changes.  The content in the matrix is the difference between the WCS and Tool Plane.

 

How position for each axis is calculated depends on your machine's configuration.  My machine is Rotary on Rotary, meaning that the B axis rotary rides on the A axis rotary.  This code calculates the positions for my machine:

          if m1$ >= 0, aabs = asin(m7$)
          if m1$ < 0, aabs = 180 - asin(m7$)
          if m5$ >= 0, babs = asin(m6$)*-1
          if m5$ < 0, babs = asin(m6$) + 180

You will need to find the proper formulas that output for your machine configuration.

 

Once you have good positioning output, then you can start adding vector calculations that add simultaneous multiaxis machining.  This is where everything gets complicated.  When one axis moves, it can change the values of all of the other axes.  The calculations to keep up with 6-Axis simultaneous will be brutal.  Each additional axis that a machine has requires an exponential increase in calculations.

 

 

[acam]

Hello,

 

we have done several posts like that before.

 

It is all done by one postprocessor  which includes logic to change output between different configurations

 

The method we use is the use of misc integer parameter to set the one of three configurations.

 

This method also enables you to "mix" different configurations within one NC file.

 

For instance:

 

Mi5$ = 1 ==> XYZAB (C= 0)

Mi5$ = 2 ==> XYZAC (B= 0)

Mi5$ = 3 ==> XYZBC (A= 0)

 

Of course it takes a lot of work to set it up (postprocessor must be practically rewritten from ground up)

Probably the hardest thing is to  correctly switch on and off all machine functions when changing configurations within one NC file.

 

One note: you will most probably not be able to achieve this by using Mastercams  Gen5ax because this postprocessor has some logic binned which prevents it to change configurations.

At first we have tried to change the Gen5ax  to get the wanted output (the one with multiple configurations) but were unsuccessful. So we created our own generic 5axis postprocessor which enables us to use up to 3 configurations within one NC file.

 

regards.

[Edi Filipovic]

Hello,

 

we have done several posts like that before.

 

It is all done by one postprocessor  which includes logic to change output between different configurations

 

The method we use is the use of misc integer parameter to set the one of three configurations.

 

This method also enables you to "mix" different configurations within one NC file.

 

For instance:

 

Mi5$ = 1 ==> XYZAB (C= 0)

Mi5$ = 2 ==> XYZAC (B= 0)

Mi5$ = 3 ==> XYZBC (A= 0)

 

Of course it takes a lot of work to set it up (postprocessor must be practically rewritten from ground up)

Probably the hardest thing is to  correctly switch on and off all machine functions when changing configurations within one NC file.

 

One note: you will most probably not be able to achieve this by using Mastercams  Gen5ax because this postprocessor has some logic binned which prevents it to change configurations.

At first we have tried to change the Gen5ax  to get the wanted output (the one with multiple configurations) but were unsuccessful. So we created our own generic 5axis postprocessor which enables us to use up to 3 configurations within one NC file.

 

regards.

 

Hello Gorazd,

 

Nice to see you here, last time we met was about 15 years ago in Ljubljana

So, is this idea you´re talking about the way to make 6 axis post ?

All this I´m thinking about is just for that reason - how to solve post for 6 axis machine, for one project I´m working on.

 

regards,

Edi

[acam]

yes,

 

this is the general idea we are using when creating 6-axis postprocessors.

We think it is the best way - it is clean (no other special external EXEs od DLLs are needed) and also all necessary mathematic functions are present in MP language.

 

Regards.