Hi All:

I am trying to simulate a 4inch drop for our product. The module layout is shown in the attached picture.

Three rubber pads are used in the module to absorb the contact shock.

As a result, the linear drop test cannot give me an accurate predication.

I have two questions for this nonlinear simulation:

1. How to model the ground for the object to hit. It should be similar to the

"virtual wall" option in static analysis but the nonlinear package doesn't provide this option.

2. How to calculate the Rayleigh damping coefficient for this system.

I understand I should calculate these values according to the system natural frequency.

However, I should calculate the natural frequency of the drop piece only or the drop piece with

ground?

Can anyone give me some suggestions on these questions?

Thanks a lot.

Zhemin

Is the material really that nonlinear that you need that?

I Thibk linear would be enough and if you needed more, you could use platixity

http://help.solidworks.com/2010/english/SolidWorks/cworks/legacyhelp/simulation/Materials/Material_models/von_Mises_Plasticity_Model_(Kinematic_Isotropic).htm

Model the ground the way it actually exists.