could not set up arangement with asm. constraints

[uwam2ie]

I'm trying to create an assembly arrangement with the new constraints in Nx504. I want to change the position of the bar on the steps. I can not understand how to create/switch ... ???deactivating constraint????
thx in ad

 

[JohnRBaker]

OK, I've updated you assembly and added several Arrangements each with a different offset value for the 'overhang' of the item on the step (file attached below).

How you do this is first set up your assembly the way you wish the default arrangement to be (I set that to have 0 overhang) and give that arrangement some name (do that by selecting the Assembly item in the Assembly Navigator and using MB3 select Arrangements -> Edit).

While still in this Arrangement Edit dialog, create one more arrangement and give it an appropriate name and the active Arrangement (just double click it) and then leave the dialog.

Now go back to the Assembly Navigator and expand the Constraints and select ONLY the constraint(s) that you wish to vary in each arrangement and press MB3 and select the 'Arrangement Specific' option. Note: Do NOT make ANY other constraints Arrangement Specific if they are NOT going to vary since the ones that are not Arrangement Specific will automatically be shared with ALL Arrangements.

Now go back to the Arrangement Edit dialog and create as many addition arrangements that you wish to. Note that for each arrangement, including the default one, if your constraint required an expression, such as the Distance Constraint used here in this example, a unique expression will be created. Now you can either edit the value of those expressions in the Expression editor or you can go back ans select the Distance Constraint and using MB3 select the 'Edit in Arrangements...' item and then you can edit all of the Arrangement Specific expression from this dialog.

Anyway, that should do it for this example.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

 

[uwam2ie]

Thank you John,
but this way has worked for me, too.
Works only with on constraint?
I want to create an arangement for each step with the block,
and that did not work with redefining the constraint in the specific arrangement.
I checked the things on arangement without constraint- that works but not / how with constraint.
Another question with the constraints, can I constrain from one Datumcsys to another, for me it only works the datum planes but I 've to do it 3 times, It would be nice...
thx in ad

 

[JohnRBaker]

Do you want to move the block from step to step? If so, there are two approaches that you can use, and while the internals of resulting models are very different, the actual steps performed are virtually IDENTICAL. Now I'm not saying that they ARE identical, as they are quite different in their behavior AFTER you've finished, and also they generally would never be interchanged one for the other.

Attached are 3 assemblies, my original one unchanged (-0) and then 2 others (-1 and -2) constructed using the two approaches.

The first approach (-1) doesn't use ANY CONSTRAINTS AT ALL!

The second approach (-2) uses what at first appearance are duplicate and/or redundant constraints and a lot of them.

However, this can serve two different purposes. The advantage of the first approach is that while each arrangement has a different offset and sits on a different step, once there you can still manually move the block if you wish to. Now in your example that is probably NOT what you're looking for, but think of something like a butterfly value (my favorite demo part). You may wish to have two arrangements, OPEN and CLOSED, yet in either case, you may still wish to move the valve flapper manually, so this first approach would be the way to go.

Now the second approach will still allow you to have the block offset differently and sitting on a different step with each arrangements, but yet in every case it remains fully constrained.

OK, how do you do this?

It's usually easier to create and name all of your arrangements first before you even start to position or constrain your component(s), but you can do these one at a time, but I think if you know up front than how many you're going to need it's more efficient to do it as I'm about to describe.

OK, assuming that you have placed and Fixed your Stairstep, have added your Block (placed just about anywhere), and you have already created 3 additional arrangements, you can start.

First set your assembly as being in the default arrangement.

Now you need to decide, do you want to have a -1 (NO constraints) result or a -2 (fully constrained)?

If you wish to have a -1 result, perform ALL of the steps below using the 'Move Component' function.

If you wish to have a -2 result, perform ALL of the steps below using the 'Assembly Constraints' function.

Open the appropriate function (if you're using 'Move Component', change the 'Type' to 'By Constraints') and go to the 'Settings' section and set the Arrangements option to 'Apply to Used'. Now 'constrain' the block to the first step with whatever offset you wish and hit 'Apply'.

Now go to the Assembly Navigator and change the assembly Arrangement to the the next one in the list.

Now repeat the 'constraining' steps above, only this time going to the next step and then hit 'Apply' again and then move to the next arrangement and repeat until finished with the last arrangement.

Now irrespective of which function you used, Move or Constrain, the results will be IDENTICAL accept as noted above.

OK, I hope that helps. Look at the examples below and hopefully between them and my description above, you will be able to figure out what you need.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

 

[uwam2ie]

thank you John,
you are doing a great job!!!!!!!!!!!!
I will look at it, the -2 result is at the first look that what I want. I thought that I can work without deactivating a constraint and redefine the constraint in the spezific arrangement.

 

[JohnRBaker]

You don't have to activate and deactivate constraints as you create the arrangements as that will happen automatically. That's why I said that the actual interactive steps to accomplish this, with or without constraints, are exactly the same.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

 

[uwam2ie]

John, I tested, reworked,
Ok it works fine in the inline process like you told.
But if I'm not working this way edit an existing arrangement,
the arrangement spezific constraint did not deactivate automatically , I have to deactivate the corresponding old constraint. Another / more an annoyance/ is that if I delete an arrangement the constraint still exist, I have to delete this manually. ... this is a really easy example. In complexer
situations, grumble.... John I hope you understand I' m not really happy with the situation...
thx

 

[JohnRBaker]

I agree with your comment about deleting Arrangement specific constraints. We need something better there. I've opened a PR covering and a couple of other Arrangement/Constraint issues. If I learn anything, I'll pass it along.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

 

[uwam2ie]

I hope we get a better solution.
Because of John I think Nx is the best Cad solution in the world. I like this short way without any indirekt CIP...
nice WE