Creating Rigid Virtual Parts

A Rigid Virtual Part is a rigid body connecting a specified point to specified part geometries, behaving as a mass-less rigid object which will stiffly transmit actions (masses, restraints and loads) applied at the handle point, while locally stiffening the deformable body or bodies to which it is attached.

The Rigid Virtual Part does not take into account the elastic deformability of the parts to which it is attached.

The program proceeds as follows:

	a node is created in coincidence with the specified handle point.
	each node of the specified geometry supports meshes is connected by a kinematical rig-beam element to the handle node.
	a set of rig-beam relations is generated between the handle node degree of freedom and the connected nodes degree of freedom.

Thus, the Rigid Virtual Part generates as many rig-beam kinematical elements as there are nodes on specified support meshes.
The Rigid Virtual Part is built with a Rigid Spider element.

To know more about this element, see Rigid Spider in the Finite Element Reference Guide.

Rigid Virtual Parts can be applied to the following types of Supports:

Mechanical Feature	Geometrical Feature				Analysis Feature
Mechanical Feature	Point or Vertex	Curve or Edge	Surface or Face	Volume or Part	Analysis Feature

This task shows how to create a Rigid Virtual Part between a point and a geometry support.

You can use the sample28.CATAnalysis document from the samples directory for this task: Finite Element Model containing a Static Analysis Case and computed corresponding Static Solution. A Part Design point was created on the associated CATPart document.

Before You Begin:
Go to View -> Render Style -> Customize View and make sure the Shading, Outlines and Materials options are active in the Custom View Modes dialog box.

1. Click the Rigid Virtual Part icon

.
The Rigid Virtual Part dialog box is displayed.

2. Select a face or an edge of the part as a geometry support. In this particular case, select a face.

3. Position the cursor on the Handler field in the Rigid Virtual Part dialog box and select a vertex or a point as handler point (the handler point symbol appears as your cursor passes over it). In this case, select a point.

	This point selected as handler must be a Part Design point.
	If you do not specifically select a point, the centroid (the point at which the lines meet) will be used as the handler point.

When several virtual parts share a same handler point, only one finite element node is generated.

4. Click OK to create the Rigid Virtual Part.

A Rigid Virtual Part object appears in the specification tree under the active Nodes and Elements objects set.

	You can select several geometry supports.
	The Rigid Virtual Part will connect all supports to the handle point and stiffly transmit all actions as a rigid body.