file stl

[romina giu]

you are right I apologize for not clarity and not to be presented initially!!!!

the stl file I have to turn it into solid and use it in dynamic simulation from contact with a cad model made by me; I wanted to know if it is possible to do such a thing.

instead for the corner : considered many cylinders extruded one on the other united by a spherical joint, after the cinematism I must measure the twist that every cylinder has carried out......... just measure the angle around the vertical axis of each. How can I do that?

thank you and sorry.....I am not used to the forums !!!

 

[cacciatorino]

I moved the discussion to the swx forum.

 

[maxopus]

the sl is not a solid file.
is a typical format of rapid prototyping and programs dedicated to reverse.
These are typically rows made up of an infinity, triangular surfaces that can be derived or exported or from a cloud of points.
to make a stl solid, you have to build on the curves, from which revenues of the superifices and from the latter, revenues subsequently the solid.

 

[romina giu]

to model the intervertebral disk I used torsion springs and then I inserted tensile springs between the vertebrae!!!! my model does not take into account the muscles !!!
I agree with the fact of the cad!!!!

 

[zeigs]

you can't measure it: each cylinder is able to rotate completely around the axis that passes through the two spherical joints. you have to give constraints that in some way define their mutual position: like the torque elasticity of the spherical joint. then it is possible that the cad solves the individual reciprocal posizins. but we are definitely not talking about solid edge.
If instead the position gives you an external program and use the solid to make measurements, then my advice is to put markers on your cylinders: At first they are all aligned, after the rotation it is enough that you misuse these markers. which can simply be a solid reference plane to the part or, if they do not affect the simulated model, heels or forellini on the solid

 

[romina giu]

In fact I put some extrusions on the solid to measure the angle... but how do I then measure it??? with measures?

 

[romina giu]

So do I always create surfaces??? Isn't conversion automatic??? I don't know I've never done it but reading the guide I thought I'd try so!!!

 

[romina giu]

In fact I put some extrusions on the solid to measure the angle... but how do I then measure it??? with measures?

 

[maxopus]

So do I always create surfaces??? Isn't conversion automatic??? I don't know I've never done it but reading the guide I thought I'd try so!!!

There is no automatic conversion to the world (I do this by craft and even if I do not use them all, I know what is the method of all reverse programs to get to a solid .... that is equal for all).

 

[cacciatorino]

So do I always create surfaces??? Isn't conversion automatic??? I don't know I've never done it but reading the guide I thought I'd try so!!!

try to work on a very simplified model (three cylinders of which one on the ground and the other two bound by these spherical joints). when you have learned to use the tool you will return to your spine.

I always do that, it's always worth validating the method before you do the tests, at least you understand if what you're doing makes sense and provides realistic and usable results.

 

[romina giu]

There is no automatic conversion to the world (I do this by craft and even if I do not use them all, I know what is the method of all reverse programs to get to a solid .... that is equal for all).

Hello I need advice,
I'm working on the stl file, I ran the mesh preparation and I have to do the superphysics, there's an option on solid that says automatic creation.... what I asked you yesterday, but so it's not okay??? Isn't it working?? In fact, for the anatomical parts it seems that it works without creating any surface it does it automaticmnete !!! what do you think???

 

[maxopus]

If it gives you a satisfactory result and you can solidify them... why not.
I don't know in the latest versions of swx what they have implemented for reverse surfaces.
when I saw him, he did few things and even with great difficulty.
He needed a simple stylus of 100,000 triangles to go to the ball.
It's likely that they improved it from this point of view.

 

[Matteo]

I had absolutely not understood rhetoric in this question!!!! I will spit to see it!!! Enough arguments obvious !!!
cmq pleasure I am creating a biomechanical model of the spine in solidworks and I ask your help .....ve i would be grateful !!!

satisfactory as a presentation? ?

Smile on the presentation speech... on the problem:

1) with a stl file you can do very little at fem level especially in case of such a complex problem where you need some control on the mesh (which with a stl must follow the various "tags")

2) contact analysis (even more than other non-linearity) is not a trivial problem to solve, although "integrated" make it look simple with a set of wizards.

3) if you are studying the model for "personal culture" or because you are a freelance designer who also has to do as a strutturist I can give you a hand (maybe in the fem section: it is not a problem of "struments" but of specific skills of the operator). If it's your company that asks you something like that, I'd say it's better to suggest you use a finite element specialist.

 

[romina giu]

Smile on the presentation speech... on the problem:

1) with a stl file you can do very little at fem level especially in case of such a complex problem where you need some control on the mesh (which with a stl must follow the various "tags")

2) contact analysis (even more than other non-linearity) is not a trivial problem to solve, although "integrated" make it look simple with a set of wizards.

3) if you are studying the model for "personal culture" or because you are a freelance designer who also has to do as a strutturist I can give you a hand (maybe in the fem section: it is not a problem of "struments" but of specific skills of the operator). If it's your company that asks you something like that, I'd say it's better to suggest you use a finite element specialist.

I actually have to finish my graduation project and I'm getting out!!!! I realized that the contact analysis is not easy!!!! If you can give me some tips I thank you I am ready to listen

 

[Matteo]

I actually have to finish my graduation project and I'm getting out!!!! I realized that the contact analysis is not easy!!!! If you can give me some tips I thank you I am ready to listen

the ideal would be to see geometry and understand exactly what you want to simulate. . for now I can only advise you to simplify as much as possible, possibly by putting aside the stl format.

the topic is very interesting!

I would propose (also to submit the problem to experts) the move (further) in the generic cae/fem/cfd section

 

[romina giu]

the ideal would be to see geometry and understand exactly what you want to simulate. . for now I can only advise you to simplify as much as possible, possibly by putting aside the stl format.

the topic is very interesting!

I would propose (also to submit the problem to experts) the move (further) in the generic cae/fem/cfd section

So you tell me if I have a stl file, I can't use it for a contact cinematism??? I think if he comes out he's so cool! the cinematism with the loads I did but not satisfy me

 

[Matteo]

So you tell me if I have a stl file, I can't use it for a contact cinematism??? I think if he comes out he's so cool! the cinematism with the loads I did but not satisfy me

I don't say that it's impossible, but it's certainly not the "furbate" way (although graphically it would be "fright"... okay).

the problem is to understand how contacts work: everything is based on control algorithms of the position of the knots of one surface compared to those of the other with which the contact takes place. So I talked about a couple of surfaces... if couples are "n" (and I think very great) complexity increases exponentially (and I write "exponentially" in the literal sense).

ok... with many pre processors (the more integrated) you can simply specify that the contact is between 2 bodies and then the software will look for the surfaces to "check"... all by relying on the speed of the hardware (5-10 years ago they didn't even dare to propose such an approach). However, it remains a difficult approach, if not in simple cases.

 

[romina giu]

I don't say that it's impossible, but it's certainly not the "furbate" way (although graphically it would be "fright"... okay).

the problem is to understand how contacts work: everything is based on control algorithms of the position of the knots of one surface compared to those of the other with which the contact takes place. So I talked about a couple of surfaces... if couples are "n" (and I think very great) complexity increases exponentially (and I write "exponentially" in the literal sense).

ok... with many pre processors (the more integrated) you can simply specify that the contact is between 2 bodies and then the software will look for the surfaces to "check"... all by relying on the speed of the hardware (5-10 years ago they didn't even dare to propose such an approach). However, it remains a difficult approach, if not in simple cases.

I understood perfectly !!! to me would be a kineamtism between a solid created starting from a stl and a set created by me, in fact they are 12 parts that I have to select for contact simulation !!! according to me it is possible !!! everything is that I can understand well how to transform the stl file into solid