Grid Point Singularity Table, NASTRAN

[saileek]

Hi,
I am trying to apply vertical force on 1d ROD element.
one end of the rod is fixed and other end has predisplacement.
This is nothing but a string of a tennis racket.
When i run this model in NASTRAN i keep getting Grid Point Singularity in Z direction.
Please tell me how to remove Grid Point Singularity without constraining the grid points.

 

[Onda]

I think you should tell us a bit more of your analysis.
How is done your model?
In which plane is your ROD element?
what do you mean with pre displacement?
in which direction is the load respect to the ROD?
Which constrain do you use on ROD ends?
Is your analysis linear or not linear?

last question .. . . are You a student? This is not a forum for students.