Stress and strain visualization on car part ( cosimulation motionsolve - edem)

Mahdi Masmoudi

Hello, 

I am running a co-simulation using motion solve and edem ( trying to follow this course : https://learn.altair.com/course/view.php?id=157 )

My issue is that I am not able to see the stress contour like here

 

 

My system is a car ( using vehicle tools from motionsolve) and i use EDEM to simulate the soil ( road)

My issue is that I am adding an arm to the vehicle and I want to see the strain and stress on that arm. I used hypermesh to create that arm and imported to motionsolve. 

My question is how to see stress and strain on that arm ?

Should I define it on hypermesh and imported to motionsolve ? Or i can simply define it as body in motionsolve? how can I request strain / stress as outputs ?

 

Any help is very much appreciated. 

Christopher_Fadanelli

Hello Mahdi,

You can generate the flexbody stress strain results both in hypermesh and MotionView.  I would highly suggest going over the MotionView elearning, there is a dedicated chapter regarding flexbodies. 

Hope this helps!

Christopher Fadanelli

Mahdi Masmoudi

Christopher Fadanelli_22565 said:

Hello Mahdi,

You can generate the flexbody stress strain results both in hypermesh and MotionView.  I would highly suggest going over the MotionView elearning, there is a dedicated chapter regarding flexbodies. 

Hope this helps!

Christopher Fadanelli

Thanks for your time to reply to this question. 

I figured out that I need to create a flexbody and include it in motion solve. Actually, now I am facing a different issue and I would appreciate if you could help me with it.

So for my simulation I need to see strain and stress on the disk crossing the soil.

What I have done so far is: Created the disk in hypermesh with properties of aliminum. I ended up with a .fem file.

Next I used PrepFlex from motionview to create the flexbody. Ended up with H3D file.

In the motionview simulation I include this disk in a body as flex.

I couple the simulation with edem and I run my cosimulation. Finally I get these results: you can see that the disk has very low values of strain and stress. I am expecting these values to be higher on the edges as the edges are in contact with soil. On the other hand I can see from edem results that the soil is loading some force on the disk which values are realistic( see figure of results from edem and hyperview) 

My assumption is that the fem model is not working for some reason even when provided with the needed external force from edem ( coming from the soil). Do you know what I could have done wrong ? 

 

 

Christopher_Fadanelli

Mahdi Masmoudi said:

Thanks for your time to reply to this question. 

I figured out that I need to create a flexbody and include it in motion solve. Actually, now I am facing a different issue and I would appreciate if you could help me with it.

So for my simulation I need to see strain and stress on the disk crossing the soil.

What I have done so far is: Created the disk in hypermesh with properties of aliminum. I ended up with a .fem file.

Next I used PrepFlex from motionview to create the flexbody. Ended up with H3D file.

In the motionview simulation I include this disk in a body as flex.

I couple the simulation with edem and I run my cosimulation. Finally I get these results: you can see that the disk has very low values of strain and stress. I am expecting these values to be higher on the edges as the edges are in contact with soil. On the other hand I can see from edem results that the soil is loading some force on the disk which values are realistic( see figure of results from edem and hyperview) 

My assumption is that the fem model is not working for some reason even when provided with the needed external force from edem ( coming from the soil). Do you know what I could have done wrong ? 

 

 

Hello Mahdi,

 

How many modes do you have associated to the flexbody? The forces are being transform from nodal to modal space, the local contact effects might not be captured correctly. This depends on the way the CMS flexbody was generated (number of eigenmodes, static modes); the higher the number of modes, the better approximation -- along with higher computational overhead. Other way to increase local accuracy at areas of interest is to enrich flexbody’s mode space with appropriate static modes.

 

Best,

 

Christopher Fadanelli