Welcome to MCAD Central

Join our MCAD Central community forums, the largest resource for MCAD (Mechanical Computer-Aided Design) professionals, including files, forums, jobs, articles, calendar, and more.

Register Log in

slow regeneration of assembly

ksboo79

New member
hi,



i donno if anyone experienced this problem but any help is great appreciated.



i have an assembly of a medium sized fixture with 4 sub-assemblies and more sub-assemblies in the subasemblies. the problem happen when i change a part that has a lot of cross references form other parts (e.g. the base plate), it would take about a second to regenerate one feature of that part. so if this part has 60 features, it'd take a long one minute just to regenerate this part.



i'm running on winXP on athlonXP 1800 with 256mb. please help me.. i'm taking coffee breaks in between regenerations of my assembly..
 

mardit

New member
One way and in my opinion the only way to get rid of this situation is to use Simplified Represenation in assembly. In that case you are able to reduce your regeneration time and drink coffee after Pro/e :).



Regards,
 

mardit

New member
One way and in my opinion the only way to get rid of this situation is to use Simplified Represenation in assembly. In that case you are able to reduce your regeneration time and drink coffee after Pro/e :).



Regards,
 

ksboo79

New member
hi mardit,



i'm sorry i don't get your point of simplified representation in assembly. can you explain in more detail?



thanks..
 

mardit

New member
In Pro/assembly in the side menu there is an item:

Simplfd Rep --> create



Then you can create that Rep. for yor assembly, but there are different options, like: Graphics Rep, it depends on your assembly that you are gonna use which of them. This simplification will speed up your regeneration time.

For more information about Graphic Rep or Geometry Rep...

I think there are some explanation in pro/help documents.



Hope this will help.
 

ksboo79

New member
hi mardit,



i've tried to simplify my model.. it do help speed up my work while twisting my model. but the problem of the slow regeration still exist.



anyway, thanks for your advice.
 

ksboo79

New member
i think i've found out the root of this problem. it's just a speculation of why it happened this way. i have replaced a sub-assembly (which have been reference by features in the main assembl) from the main assembly with another sub-assembly, assuming that proE will give error msgs for me to redefine features with lost references (but it didn't do this). instead proE search into the original sub-assembly (which is not in session) to retrieve references for features, making regeneration slow.. can anyone verify this?? there's no such problem with the first model i built which is of the same size..



thanks
 

sfrey

New member
One major factor that can increase assembly regeneration time is the use of assembly features, such as cuts.
 

jperkins

New member
Another thing you might want to consider is to add some more memory to your machine, 512Mb or more is recommended.



jperkins
 

mmead0ws

New member
Several things will affect retrieval and regeneration time. Look for some of these:



Warnings messages are an indication that Pro/ENGINEER is spending time determining what you want. Just because the geometry doesn't fail doesn't mean its efficient. Look for Geom Checks and 'cut entirely outside of model' type warnings. These are computational resource drains that can be avoided in most cases.



Assembly features like cuts do add to regeneration time. Assembly features essentially create assembly-level hidden family tables. It is cumbersome to explain, so in short, it increases regen time. Assembly features especially increase regen time when they are 'entirely outside the model'.



External references also affect regeneration time. If external references are tied to components not currently in your assembly, they will either freeze the geometry in your assembly (generally a bad thing), or they will retrieve the required model(s) in the background and verify them before updating the desired component. I think this is determined by a config.pro option, but I'm not sure. Use the Global Reference Viewer Graph to see a model tree structure of your external references.



When possible, use a skeleton model. Skeletons are part of the advanced assembly option (AAX). I figure if you are creating external references, you must have access to AAX. AAX is a group of top-down design tools that make managing large assemblies faster and easier. Use skeletons to maintain external references and to assembly all your sub-assemblies. Don't copy external references into your skeletons, only use your skeleton as a reference to other components/geometry.



Use a skeleton in conjunction with your Simplified Reps. This will reduce in-session memory usage even more. Although it doesn't help regen time. Another option is to use on-demand simplified reps. You have to turn these on with a config.pro option (open_simplified_rep_by_default = yes). Then when you open an assembly, it prompts you for the rep to open. Choose Graphics Rep and fill the check box for 'Enable On-Demand Updating'. This will open another dialog asking how/when you want to swap out components. Essentially all components start out as graphics reps. As you assemble, they change to geometry reps. If you modify a feature in a comonent, it changes to a master rep. For truely large assemblies, this is a huge time and resource saver.



How you created the geometry itself can significantly affect regeneration time. Patterns of complex cuts in some cases take much longer than if you surface transformed the cut. I've reduced regeneration times by minutes before just by using surfacing. If this is an issue, please let me know and I'll provide more detail.



You are doing the right thing by using lots of sub-assemblies. Sub-assemblies allow you to break a large assembly into manageable chuncks. Most of the time you can work on an individual sub-assembly and not have to wait on the full assembly to open or regenerate. This is a great top-down design technique.



Good Luck
 

Sponsor

Top