How is the friction set on a member hinge via the COM interface?

Answer

Friction is a nonlinearity and can therefore only be modified via the interface to the member hinge.

For this, it is first necessary to create the member hinge, if not already available. Then, the IMemberHinge interface is brought to the member hinge and then to the nonlinearity (here IFriction). Then, you can use the methods GetData and SetData to modify the data (here Friction):

Sub SetMemberHingeFriction ()

    Dim model As RFEM5.model
    Set model = GetObject(, "RFEM5.Model")
    model.GetApplication.LockLicense

    On Error GoTo e

    Dim data As IModelData
    Set data = model.GetModelData

    Dim hinge(0 To 0) As RFEM5.MemberHinge

    hinge(0).No = 1
    hinge(0).RotationalConstantX = 1
    hinge(0).RotationalConstantY = 2
    hinge(0).RotationalConstantZ = 3
    hinge(0).TranslationalConstantX = 4
    hinge(0).TranslationalConstantY = 5
    hinge(0).TranslationalConstantZ = 6
    hinge(0).Comment = "Member Hinge 1"
    
    hinge(0).TranslationalNonlinearityX = FrictionAType

    data.PrepareModification
    data.SetMemberHinges hinge
    data.FinishModification
    
    ' get interface for member hinge
    Dim imemhing As IMemberHinge
    Set imemhing = data.GetMemberHinge(1, AtNo)
    
    ' get interface for nonlinearity 'friction'
    Dim iFric As IFriction
    Set iFric = imemhing.GetNonlinearity(AlongAxisX)
    
    ' get friction data
    Dim fric As Friction
    fric = iFric.GetData
    
    fric.Coefficient1 = 0.3
    
    ' set friction data
    data.PrepareModification
    iFric.SetData fric
    data.FinishModification
    
    
e:  If Err.Number <> 0 Then MsgBox Err.Description, , Err.Source

    Set data = Nothing
    model.GetApplication.UnlockLicense
    Set model = Nothing

End Sub


In the case of the friction Vy + Vz, the Coefficient2 is used to set the second coefficient. The spring constant in the Friction dialog box is controlled by the translational spring of the member hinge. In this particular case, this is TranslationalConstantX for the X‑direction (see Figure 01).

Keywords

COM Friction Nonlinearity GetData SetData

Downloads

Contact us

Did you find your question?
If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

+49 9673 9203 0

info@dlubal.com

RFEM Main Program
RFEM 5.xx

Main Program

Structural engineering software for finite element analysis (FEA) of planar and spatial structural systems consisting of plates, walls, shells, members (beams), solids and contact elements

Price of First License
3,540.00 USD
RSTAB Main Program
RSTAB 8.xx

Main Program

The structural engineering software for design of frame, beam and truss structures, performing linear and nonlinear calculations of internal forces, deformations, and support reactions

Price of First License
2,550.00 USD
RFEM Other
RF-COM 5.xx

Add-on Module

Programmable interface (API) based on the COM technology

Price of First License
580.00 USD
RSTAB Other
RS-COM 8.xx

Add-on Module

Programmable interface (API) based on the COM technology

Price of First License
580.00 USD