×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

CG of the model in FEMAP

CG of the model in FEMAP

CG of the model in FEMAP

(OP)
Hi All,

I am trying to find the CG of my model in FEMAP in order to apply a mass element which will represent some components of my model. The problem is with Tools> Mass Properties > Solid Properties I am prompted to choose only one geometry. How can I get the CG of my model without meshing the whole model? Do I have to get the CG in cad and just create a node at the CG instead or can I do it all in FEMAP?


Thanks!

RE: CG of the model in FEMAP

"How can I get the CG of my model without meshing the whole model?" not sure you can ... meshing is how Femap understands the structure, and is where you apply density and weight.

Sure you can go through AutoCad to get the CG ... I guess that'd be a volume CG since I don't think AutoCad understands weight.
Else run Femap with three supports and determine the CG from the results.

another day in paradise, or is paradise one day closer ?

RE: CG of the model in FEMAP

(OP)
Ah alright thank you for the reply. Ill probably go through CAD.

RE: CG of the model in FEMAP

does Cad understand the weight of your assembly ?

another day in paradise, or is paradise one day closer ?

RE: CG of the model in FEMAP

This is something that can be done in Femap via API; see the code below, paste it into your Femap API programming window and try it.

Sub Main
Dim App As femap.model
Set App = GetObject(,"femap.model")

Dim sol As femap.Solid
Set sol = App.feSolid

Dim solset As femap.Set
Set solset = App.feSet

Dim area As Double
Dim vol As Double
Dim cg As Variant
Dim Inetia As Variant

Dim density As Double

solset.Select (FT_SOLID, True, "Select Solids for Mass Properties")

App.feGetReal ("Enter Density", 1E-15, 1E+16, density)

SolidID = solset.First

While SolidID > 0

sol.Get (SolidID)

sol.MassProp (area, vol, cg, inertia)

CGXw = cg(0)

CGYw = cg(1)

CGZw = cg(2)

currentmass = vol*density

mass = currentmass + mass

cgxT = (cgxw*currentmass) + cgxT

cgyT = (cgyw*currentmass) + cgyT

cgzT = (cgzw*currentmass) + cgzT

SolidID = solset.Next

Wend

cgx =(cgxT/mass)

cgy =(cgyT/mass)

cgz =(cgzT/mass)

App.feAppMessage (FCM_NORMAL, "The total Mass of the selected solids is "+ mass+".")

App.feAppMessage (FCM_NORMAL, "Center of Gravity: X = "+ Format (cgx, "0.#####")+", Y = "+Format (cgy, "0.#####")+", Z = "+Format (cgz, "0.#####")+"." )

End Sub


Regards,

Joe

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Resources

Research Report - What’s the State of Nonlinear Simulation?
Simulation is an increasingly valuable tool across the product design workflow, but not all simulations are equal. We set out to determine how engineers and product designers make use of specialized analyses, how they incorporate nonlinear simulation into their work and how they rate the available software. Download Now
White Paper – Data Security and Know-How Protection
Our data is constantly exposed to the danger of being intercepted or stolen as it wends its way over global data networks. Data security measures and measures for protecting intellectual property should not, however, first be implemented when data is exchanged – companies must lay the foundation for these measures within their own organization. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close