density calculation

[kertus]

Good morning, guys.

I created a piece with variants in family table.
despite the variations, the piece must have a set mass (which I introduce through a mass parameter that I introduced and called mass). I would like to write a report that indirectly calculates the density for each instance of the family table once the volume is known. I created a feature analysis that calculates the volume every time I open a instance of the family table but I can't find out what the volume and density parameters are to express the relationship together with the mass parameter I introduced.

Can you help me?

Thank you.

 

[DANI-3D]

Hello, and thank you for the boy.

I do this:
mp_density=peso/mp_volume(""), where weight is the mass you decide.

 

[kertus]

I'm wrong, guys.

 

[kertus]

Is there a way of understanding how ptc creo calls the parameters of analysis? mi da invalid side assignment

 

[DANI-3D]

it doesn't matter to undo the analysis features. mp_volume is a system parameter always available.

 

[kertus]

That's what he says.

 

[DANI-3D]

have you created and given a value to the parameter called mass? or, in its place in the report, put us a numerical value.
previously a valid material must be assigned to the part.

 

[kertus]

I created a parameter called mass.
frankly I didn't think it was necessary to assign a material since the density is variable for instance as a result of the volume change with imposed mass. I feel like I'm coming back.
How can I recall system parameters in the family table? where can I find a list of system parameters?

 

[DANI-3D]

... where can I find a list of system parameters?

go to the parameters and select mass property generated. you show them all.

 

[calacc]

where can I find a list of system parameters?

test in the guide, I seem to remember seeing them there

 

[320i S]

with creo you can use the material in family table the important thing is that the materials (all necessary) are loaded in the father of family and in the table the ptc_material_name (and select the material between the available ones, to avoid writing it by hand).

if you want to use the reverse system, you must have the father set up as a pre-set mass on "parameters and geometry" in the "prepara" section in the file menu.
at this point the parameters to use are no longer general ones, but alternative ones in the parameter/relations section.
alternative density, I would not say inaccuracies, but should calculate it alone, if you want to see it in family (but only see it), it should obviously be placed between the columns in tavella.

 

[Hope]

Good morning, guys.

I created a piece with variants in family table.
despite the variations, the piece must have a set mass (which I introduce through a mass parameter that I introduced and called mass). I would like to write a report that indirectly calculates the density for each instance of the family table once the volume is known. I created a feature analysis that calculates the volume every time I open a instance of the family table but I can't find out what the volume and density parameters are to express the relationship together with the mass parameter I introduced.

Can you help me?

Thank you.

Hello kertus,

to view geometric and inertial parameters in creo see image 1 or guide online.
to assign the mass to the component open parameters and go on alternative mass properties (image 2)

to assign to each variant a different mass value I would recall the pro_mp_alt_mass value in family table (image 3). If I think of something more direct, I'll take you.

 

[kertus]

hope does not work like this:

at the end I managed the following way:
-) I create a parameter I call, for example, massacre, which I put it in family table
-) recall in family table the calculated volume parameter.... a column of the type volume:fid_xx where instead of xx there is a numbering defined by creo to recognize this parameter

-) I define a relationship of type

mp_density=massaaaa/volume:fid_xx

I have not yet understood what distinguishes the alternated mass reported from those I find in analysis

 

[320i S]

if you can, put a file even wrong or test.

 

[Hope]

hope does not work like this:

at the end I managed the following way:
-) I create a parameter I call, for example, massacre, which I put it in family table
-) recall in family table the calculated volume parameter.... a column of the type volume:fid_xx where instead of xx there is a numbering defined by creo to recognize this parameter

-) I define a relationship of type

mp_density=massaaaa/volume:fid_xx

I have not yet understood what distinguishes the alternated mass reported from those I find in analysis

Hello kertus,

"mass alternate" allows you to edit the mass properties of the part, "reported mass" instead calculates the properties from 3d geometry.

for example if you have a 1mx1mx1m cube with a density of 7800kg/m^3 and calculate the mass you get 7800kg.
once produced the cube from the methylological room tell you that the cube weighs 7500kg (due to inclusions etc.) then you want to assign to your part the measured weight.

creo allows you to change the geometric and mass properties through the "mass alternations". from image 2, point 3 to previous message I have
assigned the mass I wanted to the component.

for the family table, just recall the pro_mp_alt_mass parameter and assign the desired mass to the instances you want to create.

alternative properties are very useful even when incomplete or surface geometries are received. you can assign inertial properties to parts
declared by those who send you the file, for example cg, moments of inertia, mass etc.

another way to access the mass parameters: file>prepare>model properties>mass properties--change> image4 attached (the parameters you go to change are exactly the same as the previous message).

in image4 attached you can decide whether to assign all properties (assigned) or change only some (geometry and parameters).

an interesting thing: as written a few lines above, you often do not receive complete geometries.
If, however, those geometries have been produced with creo, you can ask who produced the file to generate the mass property report (.dat) that you can import into your part. so consider to all effects the geometric and inertial properties.

As 320i s said, if you upload the "type" file, we can tell you more.

greetings

 

[Beth]

Hello.

You know how to give a zero density part?
that I will then use to do the subtraction in other parts so together I would not like to have them as an actual weight.
The only way I know is to create a semplicated representation by excluding these parts, but is it not possible to put something up?

Thank you.

 

[320i S]

Hello.

You know how to give a zero density part?
that I will then use to do the subtraction in other parts so together I would not like to have them as an actual weight.
The only way I know is to create a semplicated representation by excluding these parts, but is it not possible to put something up?

Thank you.

the only really fast to do according to me is to manage them as a family table, giving a material with a very low density whose weight is practically zero.

 

[Beth]

hi 320is agree with you, the minimum inseparable density is 1e-10 kg/mm3.

I regret that 1 meter cube weights me 0.1kg too