This option enables mapping orientations from beam elements (the connection between the beam nodes) to solid meshes for use with other composite material models in the LS-DYNA application simulations. The routine is similar to the Beam to Shell mapping option.
This section covers:
| SourceFile = STRING | Define the name and, if needed, the path of the source file (usually a *.dynain file). |
| TargetFile = STRING | Define the name and, if needed, the path of the target file. The target file should be an LS-DYNA application mesh. |
| MappingResult = STRING | Define the result filename. The mapping result is written to this newly generated file. |
| OrientationFile =HISV Nodes | Define this flag to enable transfer of orientations. It informs the program that the orientation data is stored within history variables (HISV). Alternatively, orientations can be derived from the element nodes. This method may yield accurate results if the mesh was well-aligned initially. |
| TransformedMeshFile = STRING | Specify the filename for the transformed mesh output. This option is intended solely for postprocessing of the transformation. For additional details, refer to the Transformation Options section below. |
| SourceFileFormat = LS−DYNA | The source file format. The only format available is LS-DYNA. |
| TargetFileFormat = LS−DYNA | The target file format. The only format available is LS-DYNA. |
| ResultFileFormat = LS−DYNA | The result file format. The only format available is LS-DYNA. |
| NumTargetPids = INT |
Define the number of parts in the target mesh that are considered within the mapping. This option should be followed by TargetPid#i definitions. |
| TargetPid#i = INT | Define as many part IDs as specified in NumTargetPids. These parts are considered for the mapping. |
| NumSourcePIDs = INT |
Define the number of parts in the source mesh that are considered within the mapping. This option should be followed by SourcePID#i definitions. |
| SourcePID#i = INT | Define as many part IDs as specified in NumSourcePIDs. These parts are considered for the mapping. |
Note: The options above specifically narrow down the scope of the mapping procedure to defined-part IDs. Other parts are ignored on both the source and target meshes.
|
TRANSFORMATION = YES NO |
Enable/disable the transformation option. |
|
WriteTransformedMesh = YES NO |
Flag to enable output of the transformed mesh used for mapping. This enables success verification for the transformation. If set to YES, a TransformedMeshFile must be specified (see above). |
There are three available methods for performing mesh transformation:
TRAFO_OPTION is required:
Iterative Closest Point (ICP)
Four-Points-Congruent Sets (4PCS)
TRAFO_OPTION is not required:
User-defined translation and rotation
The 4PCS method should be used with caution, as it is fully automatic and may not accurately transform stress tensors and fiber orientations between different coordinate systems. The ICP algorithm is the recommended approach.
The user-defined translation and rotation options are listed underneath TRAFO_OPTION.
Note: Transformation options are used to transform the source mesh.
|
TRAFO_OPTION = 4PCS ICP | Flag that enables specification of the desired transformation option. |
| NodalPair#i = INT INT | Define nodal pairs to initialize mesh alignment for the ICP algorithm. You can specify up to ten nodal pairs, with a minimum of three required. In each pair, the first integer represents a node ID in the source mesh, and the second corresponds to a node ID in the target mesh. Input values should be space-delimited, with each nodal pair provided on a separate line. |
| MAX_NUM_ITER = INT | Maximum number of iterations to be performed by the 4PCS algorithm. |
| GLOBAL_ERR = DOUBLE | Global error measurement to accept transformation as best fit for the 4PCS algorithm. |
| MATCHING_POINT_DIST = DOUBLE |
Maximum distance between points such that they are accepted as matching (4PCS). |
| PERCENTAGE_OF_MATCHING_POINTS = DOUBLE | Percentage of matching points for transformation acceptance (4PCS). |
Additionally, a custom sequence of user-defined transformations can be applied. These transformations are executed in the order in which they are specified and multiple transformations may be defined:
|
RotateSRC = DOUBLE;X DOUBLE;Y DOUBLE;Z DOUBLE; DOUBLE DOUBLE DOUBLE | The source mesh is rotated by a specified angle (first value, in degrees) around a defined axis. Predefined axes include X, Y, and Z. Alternatively, a custom axis can be specified by providing three space-delimited floating-point values following a semicolon (; x y z). |
| MoveSRC = DOUBLE DOUBLE DOUBLE | The source mesh is moved along the user-defined vector (x y z). |
| ScaleSRC = DOUBLE | The source mesh is scaled around the origin using the defined scale factor. |
In addition to the transformation options, you can convert the unit systems:
|
ChangeUnitSystem = YES NO | Activate/deactivate unit system conversion. |
|
SourceUnitSystem = kg - m - s ton - mm - s kg - mm - ms g - mm - ms lb - in - s | If unit system conversion is activated, provide information about the source unit system. |
|
TargetUnitSystem = kg - m - s ton - mm - s kg - mm - ms g - mm - ms lb - in - s | If unit system conversion is activated, provide information about the target unit system. |
| ALGORITHM = ClosestPoint |
The only available option is ClosestPoint. Values are mapped to the nearest node, integration point, or element center. |
|
Search_Radius = SrcEleLen TarEleLen DOUBLE | Specifies the search radius for the mapping algorithm. By default, SrcEleLen is used, which sets the radius to the average element size of the source mesh. Alternatively, you can use TarEleLen to apply the average element size of the target mesh, or provide a positive DOUBLE value to define a custom radius. |
| Scale_SearchRadius = DOUBLE | Coefficient to scale search buckets in the bucket search algorithm. |
| MapMainDir = YES/NO | This option activates main directions mapping on solid elements using the *ELEMENT_SOLID_ORTHO keyword. |
| SORT = BUCKET | Using bucket sort is strongly recommended, as it provides a substantial performance improvement for the search algorithm. |
| REPEAT = YES | Enable this option to ensure that all elements and integration points receive mapped data. When there is a significant difference in element sizes between the source and target meshes, the default bucket refinement may be insufficient to cover all points, sometimes by design. In such cases, this flag must be set to guarantee complete data coverage. |