Skip to main content
S
smilliman-21-Visitor
1-Visitor
April 13, 2016
Question

Mass Properties on ALL parts

  • April 13, 2016
  • 2 replies
  • 15739 views

We have some very large assemblies with roughly 30 to 50 thousand parts in them. We manage these with simplified reps, mostly a first level or empty rep. So a user never opens the master up, it would crash Creo. So I am looking for a way to run mass properties on a master I can not open, (because it will crash Creo).

Some ideas I have are to run the model with first level only components turned on, everything else excluded. This works but only gives me the active level.

  • I would like it to run on all components. How would I achieve this with a simplified rep
  • Tried adding config options

mp_calc_level all_models

Specifies the level of mass properties calculation.

assembly_only, all_models

assembly_only

esr_mass_properties extended

Defines whether to include all immediate components of external simplified rep into Mass Properties calculations or only defined state of design assembly.

design_only, extended

force_upd_assem_mp_in_simp_rep no

force_upd_assem_mp_in_simp_rep

Update mass properties parameters even when some of the components of the assembly are not in master rep.

yes, no, use_stored

mass_property_calculate automatic

mass_property_calculate

Calculate mass properties upon regeneration, upon save or by user request

automatic, by_request, check_upon_save

by_request

The model might need to open in a batch or no-visual mode so it can open.

  • I could run it in ModelCHECK batch
    • But how can I make it run mass properties on all models?
    • mass_property_calculate automatic This option should run mass, but will it run on all parts?
  • Then I would need Creo to save the model on exit.

Script, JLink or Toolkit not an option.

Thoughts or suggestions?

2 replies

M
mbonka2-Explorer
2-Explorer
April 14, 2016

Hello Scottb Milliman

l have just a tip for you. What about BOM table with your specific parameters?

See what l think:

- create new, empty assembly drawing

- create BOM table als you wish (fill in your paremeters and etc.)

- put BOM table into your empty assembly drawing

- CHANGE BOM TABLE "SOURCE ASSEMBLY" (see following picture)

00-BOM_table.jpg

RESULT:

A) Have BOM table with all desired parameters.

B) Have master assembly in session and can work with it.

C) DON´T HAVE TO open master assembly in graphics are (dont have to see it)

D) DON´T HAVE TO put assembly in drawing.

Hope it can helps or at least give you some idea...

Regards

Milan

    S
    smilliman-21-VisitorAuthor
    1-Visitor
    April 14, 2016

    Guess I should have added that part as well. I have a bom table that will give me the correct information I need.

    I also have added some parameters to the bom table that shows when you do Bill of material in assembly mode.

    But the catch here is still the driving assembly, it you do empty you get nothing, to get a bom, you need at least the first level components to be master.

    I tried your suggested, menu picks are slightly different than you show. But it still grabs the assembly and regenerates the model. It took 9 minutes to regenerate to model (small model) and update the bom. Which already had the first level components showing.

    The main question sounds simple enough.

    Create a bom structure with required models, run mass props, export out results. Then the user would be able to identify that the COG is at the front of the model now instead of the back.

    S
    23-Emerald III
    StephenW23-Emerald III
    23-Emerald III
    April 14, 2016

    I'm very interested in this thread. We have the same mass props problem on some models. So if you have a simplified rep with the 1st level included, it will give you the correct mass props on the repeat region?

    C
    Chris321-Topaz I
    21-Topaz I
    April 14, 2016

    Be very careful using PRO_MP_MASS. That value is only a snapshot in time. If a user changes the geometry that value does not get updated until you run the mass property report from file-> Prepare -> Model Properties -> Mass Properties -> Change -> generate report. It will also update if you have mass_property_calculate automatic but this only works if you are not working in a PDM environment as you will likely have released models that can't be modified to be updated.

    If you are using the Analysis -> Mass Properties and you have mp_calc_level all_models set be aware that despite the wording "all_models" not all models are returned. PTC says that if any components have a mass of 0 then it is working to specification to simply leave them out of the report

    Also I have opened SPR 4696442 because there are other models that should be reported for Analysis -> Mass Properties that do not. That SPR has been opened since August of 2015 with no activity.

    I created a script to dump the mass properties data into Excel and it was / is extremely frustrating to work with the way PTC has implemented their mass properties reporting.

    Consider voting for : Create a report for mass and CG of all components in subassemblies

    S
    smilliman-21-VisitorAuthor
    1-Visitor
    April 15, 2016

    Working with this many models you are always careful, one wrong menu pick and you are in regen wait time or you crash Creo.

    I would prefer to work within Creo to get this information if at all possible. Its all their, just need a way to update and extract it.

    C
    Chris321-Topaz I
    21-Topaz I
    April 15, 2016

    I agree. If you figure out a way to do it, let me know. Currently I am using the Analysis -> Mass Properties and then I am saving that as a text file and parsing / reformatting it in Excel. As I mentioned though PTC doesn't include components with a mass of 0 in that report nor do they include the component level so it is frustrating to work with.

    Terms & ConditionsCookie settingsAccessibility statement