Unable to edit definition of global coordinate system

[FieldEng]

I should be able to edit/modify the global coordinate system (CSYS) when starting a new part.  But when I open the Edit Definition dialog, the Origin and Orientation tabs are greyed out; inaccessible.  I don't understand why.  

[StephenW · Accepted solution]

This is a previous discussion on the default coordinate system.

https://community.ptc.com/t5/3D-Part-Assembly-Design/Is-it-possible-to-redefine-default-coordinate-system-and-change/m-p/535601#M69404

[FieldEng]

Stephen, 

Thank you, that's exactly what I was looking for.  It has been a while since I have used Pro/E, and I forgot a few things.  Defining the CSYS the way Sullivan explained makes a lot more sense to me.  

Do you have any resources or suggestions for setting my new "default" for my "start parts".  Now that I have done this, I know I can make this a template that I can use every time, but I don't think I ever learned how to do that in Pro/E, so I'm starting from scratch.  Thanks in advance.

[StephenW]

Once you have a file(s) saved you like and are happy with your setup, There are some config.pro settings for template files (start parts)

template_solidpart

template_designasm

and others where you set the path and filename for the part/assembly etc.

[StephenW]

And another long discussion https://community.ptc.com/t5/3D-Part-Assembly-Design/Reorientation-of-the-coordinate-point-xyz-planes/m-p/252517

[tbraxton]

This question comes up with some frequency. Would you elaborate on why you "need" to change the orientation of the default csys? Your use of the term global csys implies that you may be trying to replicate something from another CAD system in Creo. Doing this may or may not be useful for you.

I would suggest you define the problem here and ask for Creo best practices to test out for your scenario.

[FieldEng]

I didn't say that it was a "need", but it should be possible, regardless of why I want to do it.  The answer to your question is that I'm importing models into a different application where I'm conducting modal analysis.  Orienting the CSYS so that the two programs match is a time-saving step.  In either platform, the problem can be overcome, but it's a matter of not wanting to waste time on either end.  I can always start my model on the appropriate plane so that when it's imported, the features line up correctly with the respective coordinate systems.  In some cases, that would require starting a sketch on the negative top plane, or negative Front plane.  Alternately, in the receiving application, I can turn the model to orient the features to the correct axis.  Again, another step that takes time.  I don't want to have to do either of those extra steps.

That said, I have found that Sully7's solution here works perfectly for me: https://community.ptc.com/t5/3D-Part-Assembly-Design/Is-it-possible-to-redefine-default-coordinate-system-and-change/m-p/535601#M69404

[tbraxton]

For your scenario (one I deal with frequently) for import/export to other tools, I typically just add a csys feature in addition to the default csys. The location and orientation needed are set using a transform matrix applied relative to the default Creo csys. The transform matrix is typically not shared across Creo models so a template would not resolve the issue for such a use case.

Are you by any chance working with electromagnetic simulation?

[FieldEng]

Actually, the method you suggested in one that I before the other posts to this thread arrived, and that works fine.  But it's not exactly what I am looking for, because when I export a model, for example as a parasolid, I want the coordinate points to be with respect to the same global coordinate system.  It's merely a time-saving step on the import for the other program. 

No, I'm not working with any electromagnetics. 

[Patriot_1776]

The global coord sys is 0,0,0, all other things are measured FROM it, there is no reason to move it and in any case it's impossible and wouldn't make any sense anyway.  If you moved the origin, everything else would move along with it.  Where would you move 0,0,0 to anyway?  To a "new" 0,0,0???  There HAS to be a zero reference, and that's it.  Just add a new coord sys referenced FROM the global csys at 0,0,0 and use that..

Also, the orientation is based on the "Right Hand Rule":  Positive X to the right, Positive Y up, Positive Z towards you.  Simple.

[FieldEng]

Patriot_1776 - love the name, and you're not wrong, the CSYS is definitely 0,0,0.  But that's not the issue.  We aren't talking about moving the CSYS to a new 0,0,0.  It's simply a matter of reorienting the X, Y, Z axis at that 0,0,0 origin so that they have the preferred orientation w.r.t. to the Front, Right, and Top planes. 

[Patriot_1776]

Thanks,   LOL)...

Then the solution is simple:  Add a new coord sys in the location/rotation you want, and export your file using THAT coord sys.  In exporting from Creo, you can check "Customize Export", and that will allow you to choose which coord sys you want to export from.  The default is the global coord sys, but you can pick (arrow box) any one you want.  This should fix your issue.

Best of luck!

[FieldEng]

Great idea.  I hadn't gotten that far to doing the actual export, but when I was first trying to figure this out, I was wondering if I could specify the reference coordinate system.  Your way is one less step in the model creation, I think.  I will definitely give it a try.

[StephenW]

@FieldEng 

Just to clarify, if you have "named" datums (front, right, top, or whatever), those are part of your start part. They are 100% customizable. An empty start part is really empty, no planes, no csys. 

If you are trying to make your csys agree with your planes, you can name your planes however you desire. Along with that concept, the saved views, if you have them are also added to your start part, so if those don't agree with what you are expecting, change them so they are as you desire.

Really, the only NOT customizable thing is the default coordinate system orientation and position.

[FieldEng]

Stephen, yes, I figured that out by investigating the options for editing the Options, and the Edit Definition for the planes.  I may not always use it, but I like having the option to have the start part be completely empty.  For some models, they may not adhere to the standard that I'm using now, so it's nice to know that I can customize it.  

I have used the saved views in the past ... long time ago with Pro/E.  I don't need them now, but I am familiar with how to orient those as needed, or define new ones.