Building Flex Body Models - Kxcad.net

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Adams/Flex
Creating a Flexible Body in Adams/View
When you create a flexible body in Adams/View, Adams/View reads the modal neutral file (MNF)
defining the body and creates the necessary Adams/View geometry for displaying the flexible body. It
also creates a mesh on the flexible body representing the flexible body elements and nodes. You can
simplify the mesh geometry as explained in Substituting Outline Graphics for the Finite Element Mesh.
Adams/Flex places the flexible body so the flexible body's local body reference frame (LBRF) is at the
origin of the global coordinate system. The LBRF corresponds to the origin of the FE environment in
which the body was originally modeled. You can also set the location of the flexible body as you create
the body using options in the dialog box or move the body later as you do any element in Adams/View
using the Move tool stack on the Main toolbox.
After you import an MNF into Adams/View, you can use the Info tool to examine pertinent data about
the flexible body.
To import an MNF into Adams/View:
1. From the Build menu, point to Flexible Bodies, and then select Adams/Flex.
The Create a Flexible Body dialog box appears.
2. In the Flexible Body Name text box, enter the name you want assigned to the flexible body.
3. In the Modal Neutral File Name text box, enter the name of the MNF. .
Note: When you use the Browse command to search for a file, it places the absolute path to the
file in the text box. When you save the database or a command file, Adams/View uses the
absolute path in the saved file. If you are sharing the database or command file with other
users, you may want to edit the path that the Browse command places in the text box so it
is a relative path or remove it altogether if the MNF file is in the current working directory.
4. To set the damping ratio to one other than the default: (a) clear the selection of default, and (b)
in the Damping Ratio text box, either:
• Enter the critical damping ratio.
• Enter a function. To get help building the function, next to the Damping Ratio text box,
select the More button . The Adams/View Function Builder appears. For information
on using the Function Builder, see the Adams/View Function Builder online help.
5. Set Generalized Damping to one of the following:
• Off - Disables the generalized damping. - Disables the generalized damping.
• Full - Enables the complete generalized damping matrix, including the effects of a resultant
damping force.
• Internal Only - Only enables the portion of the generalized damping matrix corresponding to
the modal coordinates (that is, ignore the resultant damping force).
6. Position the flexible body by doing one or more of the following: