PROBLEMS WITH DEFINING GEOMETRY FOR TOPOLOGY OPTIMIZATION

Regina de Quiroga Tello

Hello,

I'm having problem with preparing the geometry for topology optimization. I want to optimize a lower control arm, which has 3 constraints: 2 bushings and 1 pin/bolt . My problem is that I cannot define the bolt/pin properly, and when I optimize the componente, the structure doesn't match the requirements. Find below the geometry of the component I'm working with:

a) BAseline

Geometry CAD in inspire

c) constraints: Type of supports: Bushings and pin

D) Results of topology optimization

 

 As you see, these results are not valid.... How can I fix this and get the results I need??? 

I have tried to join the bolt to the part, but then I cannot select it as non-design space.... and when I select it as non-design space, it tells me that OptiStruct does not support joining contacts..... 
I have also tried to keep as non-design space the lateral surface together with the final bolt, but as it is a surface and not a solid, I cannot optimise it or analyse it structurally either.

 

I need to solve this problem ASAP, and i've been trying to fix it for 5 days... 

Thank you very much

Johan_Dahlberg_2011

Hi Regina
Looks like you need to work with your loads and constraint a bit, also the optimisation set-up!
If there is no load transferred to "B" and you ask the software to just use some portion of the weigth it would simple "remove" unloaded material!

//johan

Ximena

Hi Regina!,

I hope that you are doing well.

In addition to the previous answer from my colleague, I would like to suggest the following:

- Add the connecting piece (red circle) to your model, this way it will look like an assembly.

In the same way, create and add the fastener in "B" (blue circle) so that you will have 3 parts: the main body that you want to optimize, part in red circle and he fastener "B".

After doing that, click on the Fastener > Property Editor > Optimization > Activate "Enable".

This option allows to include the fastener during the optimization.

 

Also, you can take as reference this example:

https://help.altair.com/inspire/en_us/topics/inspire/tutorials/tut_conn_grounded_c.htm?hl=fastener,optimization

 

I hope that you will find it useful.

 

Kind Regards,

Ximena Z.

Regina de Quiroga Tello

Johan Dahlberg_20306 said:

Hi Regina
Looks like you need to work with your loads and constraint a bit, also the optimisation set-up!
If there is no load transferred to "B" and you ask the software to just use some portion of the weigth it would simple "remove" unloaded material!

//johan

Hello Johan, 

There is no load transfer to B beacuse its a fixed support. 

Thank you

Regina de Quiroga Tello

Ximena Zepeda_21572 said:

Hi Regina!,

I hope that you are doing well.

In addition to the previous answer from my colleague, I would like to suggest the following:

- Add the connecting piece (red circle) to your model, this way it will look like an assembly.

In the same way, create and add the fastener in "B" (blue circle) so that you will have 3 parts: the main body that you want to optimize, part in red circle and he fastener "B".

After doing that, click on the Fastener > Property Editor > Optimization > Activate "Enable".

This option allows to include the fastener during the optimization.

 

Also, you can take as reference this example:

https://help.altair.com/inspire/en_us/topics/inspire/tutorials/tut_conn_grounded_c.htm?hl=fastener,optimization

 

I hope that you will find it useful.

 

Kind Regards,

Ximena Z.

Dear Ximena, 

As mentioned, i cannot add the load on point B beacuase its a fixed support: pointB doesn't allow movement in any direction, like a flush-mounted bracket.

Creating and adding a fastener will complicate thinks, as i am not very good with skecthing.... This is what im working with: the translation in X, Y, Z direction and rotation around Y, Z axis of point A is constraint, so to simulate this i have used bushings:

- Bushing in poit A1 and  A2 are simulated with conetion type Bushing of sharefile, I have created a "ball" and the conection between the ball and the structure is type bushing

- force is applied in bushing connection in point A1, for now i till be only vertical force, but im thinking including longitudinal and horizontal forces...

- point B is a fixed support

The problem now is that i loose the conection between the hole part and the bushing A2, and with this type of conection i dont have the option you mentioned of  "Property Editor > Optimization > Activate "Enable""

What do you suggest?