create solid from stl

[louisdanao]

i need to create a solid part from an stl file. the stl is of a section of the spine exported from a medical imaging software. i cant seem to use the solidify function (not available). i was able to refine the surface but after that, no luck.

 

[csusie]

To make a stl model into a solid you need REX (reverse engineering extension) or a lot of time on your hands to rebuild it manually

 

[design-engine]

restyle and rex are the same and wildfire 5.0 has the restyle tool more like ISDX in functions and iconography BTW.

http://www.ptc.com/WCMS/files/35607/en/35607en_file1.pdf
Edited by: design-engine

 

[louisdanao]

wont restyle generate a surface and not a solid part?

 

[jeff4136]

> wont restyle generate a surface and not a solid part?


What is a 'solid' if not a closed shell (quilt) with
additional attributes (e.g. has been 'Solidify'd)?


Your first pic is obviously a faceted rep (I assume
a facet feature vs. analytic or spline surfaces).


Not sure about the 2nd one.


"was able to refine the surface";
How? What modules are you using?
Have you got a refined mesh or surfaces / quilt(s)?
Open or closed?


It helps to know what your experience level is.
Is this your first taste of Pro/E?
Surface b-rep modeling in general?
Do you know the difference between a 'mesh' or 'facet'
entity and a 'surface' entity? What 'one sided' and
'two sided' edges are?


Why do you need a 'solid' part?

 

[design-engine]

Landing Gear require clearance over a range of motion as they close inside the fuselage compartment for example. I doubt that is whats going on in the above pictures but converting facet data is a challenge that is often required.

Often for a mechanism Pro/MECHANISM assembly designers want to check interference over a range of motion.The mechanism software will generate a mesh/stl/polygon shape of that range of motion. Often in my surfacing classes a participant will ask to convert that polygon to a surface then solid for interference checks over the range.

To create a solid from that range of motion would be a great enhancement of Pro/MECHANISM BTW.
Edited by: design-engine

 

[jeff4136]

> To create a solid from that range of motion would
> be a great enhancement of Pro/MECHANISM BTW


Help
.Mechanism Design Extension
..Results
...Playback
....To Create a Motion Envelope
---------------
6.In the Output Format area of the dialog box,
specify one of the following output file formats:


. Part (selected by default)

 

[louisdanao]

> wont restyle generate a surface and not a solid part?


What is a 'solid' if not a closed shell (quilt) with
additional attributes (e.g. has been 'Solidify'd)?


Your first pic is obviously a faceted rep (I assume
a facet feature vs. analytic or spline surfaces).


Not sure about the 2nd one.


"was able to refine the surface";
How? What modules are you using?
Have you got a refined mesh or surfaces / quilt(s)?
Open or closed?


It helps to know what your experience level is.
Is this your first taste of Pro/E?
Surface b-rep modeling in general?
Do you know the difference between a 'mesh' or 'facet'
entity and a 'surface' entity? What 'one sided' and
'two sided' edges are?


Why do you need a 'solid' part?

when i said "surface" i meant just a shell with nothing inside. the "refined surface" that i mentioned was just the "refine" option in the "facet feature definition". basically smaller triangles to make it look smoother (2nd pic). solidify option is not available when i import the stl.

this is not my first crack into proe but i have very limited experience. i was able to do surface and solid modeling before using ibl files but beyond that no more. no idea what surface b-rep modeling is. sorry.

i need a solid part because i need to put this into ansys for stress analysis.



Edited by: louisdanao

 

[jeff4136]

> when i said "surface" i meant just a shell with nothing inside.


Just for reference; a solid is just a shell with nothing inside.
It is, however, a volume bounded by analytic or spline surface
(a.k.a. 'normal geometry') vs. facet objects in Pro/E. That is
the essence of 'surface b-rep (boundary representation) modeling'.


> the "refined surface" that i mentioned was just the
> "refine" option in the "facet feature definition".
> basically smaller triangles to make it look smoother
> (2nd pic). ... limited experience.
> i need a solid part because i need to put this into
> ansys for stress analysis.


Well, I'm out of my element, too, a Foundation kinda guy.


If you have REXX / ReStyle you should be able to create
'normal geometry' over your Facet model as has been mentioned.


Other than that I'd look into what Ansys can do with the
Faceted b-rep you apparently have. If it's a closed mesh
Ansys may recognize it as a 'solid'.


Someone else may know of other ways to proceed but they're
probably going to be dependent on whatever extension modules
you may or may not have.

 

[louisdanao]

> when i said "surface" i meant just a shell with nothing inside.


Just for reference; a solid is just a shell with nothing inside.
It is, however, a volume bounded by analytic or spline surface
(a.k.a. 'normal geometry') vs. facet objects in Pro/E. That is
the essence of 'surface b-rep (boundary representation) modeling'.


> the "refined surface" that i mentioned was just the
> "refine" option in the "facet feature definition".
> basically smaller triangles to make it look smoother
> (2nd pic). ... limited experience.
> i need a solid part because i need to put this into
> ansys for stress analysis.


Well, I'm out of my element, too, a Foundation kinda guy.


If you have REXX / ReStyle you should be able to create
'normal geometry' over your Facet model as has been mentioned.


Other than that I'd look into what Ansys can do with the
Faceted b-rep you apparently have. If it's a closed mesh
Ansys may recognize it as a 'solid'.


Someone else may know of other ways to proceed but they're
probably going to be dependent on whatever extension modules
you may or may not have.

i have restyle. i tried to use it and i already have the "normal geometry" that you mention.

i may be using inappropriate/incorrect terms when i asked for help, which goes to show my limited knowhow with using proe. i need some sort of a volume, not a shell, so that when i do finite element analysis, i have a solid object, not a hollow structure.

any help would be highly appreciated.

 

[jeff4136]

> i have restyle.
> i tried to use it and i already have
> the "normal geometry" that you mention.


Are you certain?
If you set your selection filter to Quilts can you select what you
see in the graphics window? If you set your selection filter to
Geometry can you select individual faces, edges, vertices?


> i may be using inappropriate/incorrect terms
> when i asked for help, which goes to show my
> limited knowhow with using proe.


Not a problem but this goes beyond 'using Pro/E' to using any b-rep
modeler, as do some of the terms used. In fact; Pro/E, as do most
programs, make things a little harder by not using a common language
to describe entities and definitions.


> i need some sort of a volume, not a shell,
> so that when i do finite element analysis,
> i have a solid object, not a hollow structure.


And to further complicate things we're mixing b-rep concepts and
descriptions with those used in finite element analysis and programs.


A 'shell' is analogous to a 'quilt' in Pro/E. It is one or more
surfaces with 'topology'. Topology describes the information (database
entities; attributes, flags, etc.) linking one surface to adjacent
surfaces by creating what Pro/E calls 'two sided' edges which I asked
about previously. The generic term is 'manifold edge'.


A 'volume' is a space defined by a CLOSED shell (/ quilt). The closed
shell differs from the constituent OPEN shells (/ surfaces / quilts)
in its topology. Without that the program does not know the volume
exists even though the graphic representation indicates it does to the
user / viewer.


A 'solid' is a closed shell (/ volume definition) with additional
database attributes, i.e. 'density'. Other 'solid' database entities
can link to additional closed shells (/ volumes) defining 'void'
spaces. Shell 'normal directions' (topology) can indicate interior
and exterior shells or be set appropriately. The details of it all
get pretty complicated, well beyond what I have a firm grasp on.
Studying IGES or STEP specifications can provide a lot of clues and
definitions. Likewise reviewing export and import log files once you
understand some of the terminology.


There is no b-rep equivalent to finite element solid elements or
nodes inside the shell. (In fact finite element nonmanifold concepts
conflict with the concept of a manifold b-rep object which the
average 'solid modeler' is based on.)


So repeat after me (a more precise version of a previous statement);
"A b-rep solid is a shell with nothing inside.". ;^)


A volume (or a solid) can also be defined by a closed mesh. Each
program's developer determines whether or not that happens. Pro/E
does not. AutoCAD does (its pre-CSG, pre-ACIS solids were described
by mesh entities). Ansys might. Have you checked?


[You know; I suggested that the basics of this stuff should be the
first thing a 3D CAD user be taught in an entry level mechanical CAD
program forum. The consensus among that program's "experts" that
voiced their opinions was that the information is irrelevant to
'todays solid modeling' and that I should take a class and get up to
speed.]


Anyway, getting back to your specific model...


If you do have 'normal geometry', e.g. quilt(s), and you cannot
Solidify then there is no valid defined volume and you need to look
for one sided edges to close it up, look for self intersecting
surfaces, etc.


If you don't, and "smaller triangles" leads me to believe you don't,
I can't help with the specifics of surfacing a facet model with
ReStyle but maybe someone else can and will. Failing there I might*
be able to suggest a way to convert the faceted b-rep to a (faceted)
surface b-rep / solid if you have access to AutoCAD or Rhino. If Ansys
insists on interpreting an imported faceted b-rep as shell elements
converting to planar analytic or spline faces may be all it takes to
trick it into treating it as a volume / solid.


If you have ReStyle; do you also have Mechanica? Is there a way to
solid mesh, which I assume you want, what you have and export to Ansys?

* Rhino has a function. If I remember correctly Acad IGES exports
can write out copious data (facets) as either mesh or surface entities.
A very dense mesh (many vertices) may present problems either way.
Importing as a planar faced solid may also lock you into solid mesh
results you don't really like, too.

 

[louisdanao]

i'm dead.


> Are you certain?
> If you set your selection filter to Quilts can you select what you
> see in the graphics window? If you set your selection filter to
> Geometry can you select individual faces, edges, vertices?haha i thought i had it. nope, i dont have a quilt, not even a point. i cant seem to put a surface on to the faceted feature. i tried putting curves but its going to be very tedious to reconstruct the whole thing using this method. to make things worse, i actually have more than 5 spinal sections (from 5 patients) to analyze!

> If you have ReStyle; do you also have Mechanica? Is there a way to
> solid mesh, which I assume you want, what you have and export to Ansys?

i dont have mechanica. if i can just export it as at least an iges then ansys can easily do the meshing and anything after that.

 

[Jo_T]

Louisdanao,


I don't know if you ever found a solution to your problem, but here is my suggestion.


Use the Shrinkwrap functionality to create afacetedsolid from your stl.


File/Save a Copy/ scroll to "shrinkwrap" in the file type at the bottom of your dialog box.


Once in the Create Shrinkwrap dialog box


"creation method" select/Faceted solid/


"quality" change the level to what you want (1-10)


"special handling" since you have a stl file you can leave it with the defaults


"output"


make sure /part/ is selected


Note that there is a template option available and if you would like to specify which start part to use, you will need to unselect the /Use default template/


Select the option for solid faceted

 

[Thiago Souza]

Louisdanao,


if you want to transform .stl in a part solid try this:


1 - Save a copy


2 - choice de typeoption "product view *.ed"


When you to open the new archive, choice the PART option.


I hope that this help you.