Browsers supply a great deal of view-related functionality in HyperMesh by listing the parts of a model in a tabular and/or tree-based format, and providing controls inside the table
that allow you to alter the display of model parts.
Perform automatic checks on CAD models, and identify potential issues with geometry that may slow down the meshing
process using the Verification and Comparison tools.
The Domains and Handles approach involves dividing the mesh into domains containing elements or nodes and placing
handles at the corners of those domains.
Each global domain is associated with any number of global handles. Global handles will only influence the nodes contained
within their associated global domains. Global domains and handles are best for making large scale shape changes to the
model.
Each local domain is associated with any number of local handles. Local handles will only influence nodes contained within
their associated local domains. Local handles are intended to be used to make small scale, parametric changes to the model.
Partitioning is a method of dividing 2D domains into smaller 2D domains at logical places, such as at the edges of surfaces
associated with the mesh, or where the angle between elements exceeds a certain value, or where the domain changes from
flat to curved.
Space frames are models that have a sparse distribution of elements, such as a car body. Space frame models can generally
have element counts in the hundreds of thousands, but their basic structure is rather simple.
Shell models are models that are made up primarily of shell elements, namely, quads, and trias. In general, a shell
model represents many parts, each with numerous features such as holes and edges, and connected together using 1D
elements such as bars and rigids.
Solid models are models that are made up of solid elements, namely, tetras, pentas, and hexas. In general, a solid
model represents a single part with numerous features such as holes, edges, bosses, flanges and ribs.
The Domains and Handles approach involves dividing the mesh into domains containing elements or nodes and placing
handles at the corners of those domains.
Each local domain is associated with any number of local handles. Local handles will only influence nodes contained within
their associated local domains. Local handles are intended to be used to make small scale, parametric changes to the model.
Each local domain is associated with any number of local handles. Local handles will
only influence nodes contained within their associated local domains. Local handles are intended
to be used to make small scale, parametric changes to the model.
A model can contain both global and local handles and domains, which allows for both large
and small scale morphs. It is not necessary to have both types of domains and handles in a
model.
Local domains are represented by a single rectangle for 1D domains, two joined rectangles
for 2D domains, a cube for 3D domains, four joined rectangles for general domains, and a
line for edge domains.
Local handles are colored orange if they are not dependent on other handles. Local handles
are colored green, blue, or pink if they are dependent on other handles, the color
indicating their level of dependency. The base size of all the handles in the model can be
set on the morphing Visualization Controls tab accessed by using the Visualization Options
icon () on the Visualization toolbar. The
size given is used as the diameter for the independent local handles. You cannot edit the
color of the handles nor the relative size between the dependent and independent handles.
However, you can edit the color of the domains in the morphing Visualization Controls
tab.
Local domains can be created individually by selecting nodes or elements in the Domains
panel, Create subpanel. When local domains are created, HyperMorph automatically places local handles at the ends of all edge domains. These local handles
are named local followed by a number. The placement of local handles depends on the type of
domain created and the partitioning options, if partitioning is selected.
In Figure 1, the rigid elements have been placed in a 1D domain with the center node having an
independent (orange) handle and the other nodes having dependent (green) handles. The shell
elements have been placed in two 2D domains separated at the bend line due to partitioning.
The solid elements have been placed in a 3D domain. Shell elements have been created on the
faces of the 3D domain. These elements are placed in a component named ^morphface. 2D
domains have been created on the faces of the 3D domain and that edge domains have been
created on the edges of all the 2D domains. Handles have been placed at the ends of all the
edge domains.
1D Domains
1D domains are made up of 1D elements, such as bars and rigid elements.
When automatically creating local 1D domains, 1D elements that share common nodes are
grouped together into 1D domains. An independent local handle is placed at the centermost
node of the 1D domain and dependent local handles are placed at every other node of the
elements in the 1D domain. The independent handle is larger and orange, while the dependent
handles are smaller and green. All the dependent handles in a given 1D domain are directly
dependent on the independent handle. This dependency relationship means that moving the
independent handle also results in moving the dependent handles the same amount in the same
direction. This is done to preserve the unique relationship established for groups of 1D
elements. Additionally, the bias factors for the dependent handles for a 1D domain are given
an initial value of 3. All other handles in the model are given a biasing factor of 1. A
higher biasing factor means that a given handle will have greater influence over the
surrounding mesh than the others. The higher biasing factor given to dependent handles on 1D
domains is intended to prevent mesh distortion when the 1D elements connect to nodes in 2D
and 3D domains.
2D Domains
2D domains are made up of shell elements.
When automatically creating local 2D domains, shell elements that share common nodes are
grouped together into 2D domains. If partitioning has been selected,
these domains are subdivided into smaller domains along break angles and curvature changes
according to the partitioning parameters. Edge domains are placed along the edges of the 2D
domains and are also partitioned. Local handles are placed at the ends of all the edge
domains. In general, the local handles are placed at the corners of the 2D domains and at
other useful positions. The intent is to make it faster and easier for you to apply
parametric changes to the model. Since you morph the model by moving handles, it helps to
have handles already at the positions where you want them. HyperMorph tries to predict where the handles should be placed to
reduce the amount of time it takes to prepare your model for morphing. If the handles or
domains are not laid out in the positions where you want them to be, you can delete them,
edit them, or create new ones. Also, even though the generated local handles are associated
with the edge domains, they will influence the nodes in any domain that shares the node at
which it is placed. This is true even if the handle is associated with the 2D domain. A
handle associated with any domain will always influence the nodes in domains that it is
touching. Note that it is possible to create a handle on a node that is not touching the
domain to which it is associated. This allows you to place a handle outside of a domain,
such as floating in space near the domain, and have it influence the nodes within its
domain.
3D Domains
3D domains are made up of solid elements.
When automatically creating local 3D domains, solid elements that share common nodes are
grouped together into 3D domains. Shell elements are created on the faces of each 3D domain
and placed into a component called ^morphface. It is recommended that you do not delete or
edit these elements nor rename or delete the ^morphface component. However, if you do, these
elements and their 2D domains will be regenerated the next time you enter or exit a HyperMorph panel or the Delete panel. The shell elements on the face of
each 3D domain are placed into a 2D domain that is then partitioned if the
partitioning option is active. Edge elements are placed around each
2D domain and local handles are created at the ends of each edge domain. In cases where
shell elements that are attached to the faces of solid elements are present in the model,
HyperMorph will not create ^morphface elements coincident with
the existing elements. The color of the ^morphface component can be changed on the morphing
Visualization dialog accessed by using the Visualization Options icon on the Visualization
toolbar.
Note: The face elements in the ^morphface component will not be written out to any
FEM formatted deck since the component name begins with a "^".
Edge Domains
Edge domains are made up of a list of nodes.
When automatically creating local edge domains, edge domains are placed around the edges of
all 2D domains. When you are selecting domains and are holding the mouse button down while
placing the mouse over the icon of a 2D or 3D domain, or an element in the domain, HyperMesh will highlight both the domain icon and the surrounding edge
domains. This makes it easier for you to tell which domain you are selecting. When you
release the mouse button, only the icon for the domain remains highlighted.
Edge domains and 2D domains on the faces of 3D domains play an important function in
determining the influences for the handles over a given domain. Nodes on edge domains will
only move as a function of the handles touching the edge domain. No other handles will
affect the nodes on the edges. Similarly, nodes in a 2D domain on the face of a 3D domain
will only move as a function of the handles touching the 2D domain. This preserves the
boundaries of 2D and 3D domains such that straight edges remain straight, flat surfaces
remain flat, and curved edges retain their curvature. It allows you to move handles within a
2D or 3D domain without affecting the edges. If you do not want to have the boundaries of a
domain preserved, you can delete the edges for a given domain, or choose to create the
domain as a general domain instead. Also, non-reflective symmetries allow the influences of
handles to extend through edges and faces depending on the type of symmetry. For domains
that have non-reflective symmetry types, the boundaries may not be preserved during
morphing.
General Domains
General domains are made up of any combination of 1D, 2D, and 3D elements.
General domains are not automatically created when automatically generating local domains.
Like all other domains, the elements within a single general domain must touch one
another.
When a general domain is created, no 2D domains are created on the faces of any 3D elements
and no edge domains are created either, thus no handles are created for the domain. However,
general domains respect all neighboring edge domains and 2D domains and thus if you create
2D and edge domains for your general domains they will impose restrictions on handle
influences for the general domain. Otherwise, handles on a general domain freely influence
all of the nodes inside the general domain, allowing it to stretch and deform in an
unbounded manner with morphing extending across differences in element type. General domains
are very useful for realized connectors which are often represented as clusters of different
element types. Another use is for meshes where precise changes are required for one section,
where 1D, 2D, and 3D domains are used, but the rest of the mesh, where a general domain is
used, can simply follow along.