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Assembly sequence using constraints?

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munners

Marine/Ocean
Jul 11, 2009
33
Hi guys

When doing an assembly sequence, is there a way to access either an existing arrangement or position a component using assembly constraints? Neither of these commands seem to be available when in the sequence toolbar?

Using NX 7.5

Thanks

Munners
 
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No, the Assembly Sequence function starts in whatever Arrangement was set when you entered the 'task' and you created a saved sequence. The only 'access' to constraints that you have while in a Sequece is an option to either accept the model as constrained or to override the constraints. And the only 'access' to Arrangements is that when playing back a sequence, at any point you can stop it and SAVE whatever position the Components are in at that moment as a NEW Arrangement.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
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To an Engineer, the glass is twice as big as it needs to be.
 
Thanks John

I understand what you are saying but cannot get the sequence to run correctly. I have made sure that Assembly constraints are on in the Sequence Navigator but still have the same problem. I have attached the assembly and a movie to show what i am experiencing. In modelling, the motion of the seat is controlled by changing the distance constraint through a range of 0 to 295.
Thanks for your help

Munners
 
 http://files.engineering.com/getfile.aspx?folder=12d93939-2437-4975-bb55-eefba84c72de&file=Aft_Seat.zip
OK, attached is my take on your assembly. I know what you tried to do but that's not how sequencing works. Sequencing works by moving Components and in this case allowing the rest of the Component to move based on the constraints applied to them. Note that I deleted your old sequences but I did leave all you Arrangements intact. I did create a new one called 'Movable'. I also create one new component (pin) which consists of only a single like (which is hidden in the assembly). I used it to define the component that I was going to drive using a sequence. The line, called 'Pin.prt' simply represented the centerline of the 'pin' which runs in the guides on the sides of the case. In my arrangement I suppressed the 'Distance' constraint and added an alignment of the 'pin' and the pins on the seat. Anyway, if you look at what I've done I think you'll figure it out. Open the assembly and play the sequence.

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
 http://files.engineering.com/getfile.aspx?folder=35661e4b-72d7-4682-b53f-69778ab82f9e&file=munners_(Eng-Tips).zip
Hi John

Thanks for the help.

Just to make sure I understand, you added the arrangement called 'Movable' because it does NOT ignore constraints? And the 'pin' component was added so that you have better control over the assembly, i.e. you can simply re-position that component and the other components will move as dictated by their assembly constraints? If I am understanding correctly, that makes perfect sense to me and I can follow the logic. What I cant understand then is why I seem to be getting a different result (see attached movie of the sequence in the assembly you sent me - presumably that is not what you intended....) Is there another setting somewhere that I have missed? Is there a different version that might be causing the differences? I'm running NX 7.5.4.4

Thanks again

Munners
 
I don't know what the problem is. I'm running NX 7.5.5.4 and the sequence runs just fine, as seen in the attached video, without making any changes after simply opening my version of the assembly (and I've verified that I made no changes to any parts other than the ones that I created or renamed).

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.
 
 http://files.engineering.com/getfile.aspx?folder=37688ddf-a770-472e-856a-a4e062dbfbd6&file=movie-JRB-1.avi
Hi John

Maybe its 7.5.4.4 as opposed to 7.5.5.4?

I'll try the update

Thanks for your help

Munners
 
Fixed!

Must be a bug in 7.5.4.4

Munners
 
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