*createelements1d

Creates 1D beams, bars and rods, and optionally assigns properties to created elements.

Syntax

*createelements1d entity_type <option1>=<value1> <option2>=<value2> ... <optionN>=<valueN>

Type

HyperMesh Tcl Modify Command

Description

Creates 1D beams, bars and rods, and optionally assigns properties to created elements.

Inputs

entity_type
The type of entity to use as input. Valid values are nodes and lines.
mark=<mark_id> or list=<list_id>
The ID of the mark (for nodes) or list (for nodes). Valid values are 1 and 2.
beamsection=<beamsectionname>
If provided, an auto 1D property is created to which this beam section is assigned. The property card image depends on the elemtype provided. This property is assigned to the newly created 1D elements. In case both property and beamsection are provided, property takes precedence. This option is supported for OptiStruct, Abaqus and Nastran only. For properties that do not support beam sections, the relevant attributes (for example, area) of such properties are updated by copying values from the beam section.
biasintensity=<biasintensity>
The biasing value of the element length to use.
biasstyle=<biasstyle>
The style of biasing to use. Valid values are:
0 - Linear
1 - Exponential
2 - Bell curve
breakangle=<breakangle>
If the angle between the lines’ tangents at a joint is greater than this value, the line is split to force a node at that location. If set to 0.0, no split will occur. useshell is not considered if this is > 0.
elemconfig=<elemtype>
The config of 1D element to be created.
elemdensity=<elemdensity>
The element density to use.
elemsize=<elemsize>
The size of the 1D elements to be created. This input will not be considered if useshell is 1.
elemtype=<elemtype>
The type of 1D element to be created.
engineeringconfig=<value>
The configuration of the created entities (bar2/bar3 or rod) based on the attached shell for stiffener meshing or using meshorder if mesh is not a stiffener mesh attached to the shell. This option requires propcardimage to be defined.
linecomp=<linecomp>
The component in which the 1D elements are to be created. This option works only if entity_type is lines. Valid values are:
0 - Current component
1 - Line component
orientvec=<x,y,z>
If provided, specifies a custom orientation for 1D elements when useshell=0 or useshell=3.
propcardimage=<value>
The property card image for automatic property creation from beamsection. Ignored if property is specified. If specified together with elemconfig and elemtype, a validity check is performed to ensure compatibility of the property card image with the specified config/type. If the property card image is invalid, it will be reset to a valid default property.
property=<propertyname>
If provided, the property is assigned to newly created 1D elements. Also, it will ensure that the created 1D elements are of a type compatible with the property card image, thereby overriding the elemtype value. This option is supported for OptiStruct, Abaqus and Nastran only.
proximitytolerance=<proximitytolerance>
The proximity tolerance used to find the nearest shell nodes a long the line. Default is -1.0. Used when useproximity=1 and useshell=3.
useelemdensity=<useelemdensity>
0 - Do not use elemdensity
1 - Use elemdensity
useproximity=<useproximity>
0 - Do not use shell element nodes which exist along the line to create the line mesh.
1 - Use shell element nodes which exist along the line to create the line mesh.
useshell=<useshell>
If set to 1 or 2, considers neighboring shells of selected lines/nodes of a meshed surface for connectivity, orientation, and offset. After creation of 1D elements, the normal and thickness of these shells are used to orient and offset the 1D elements appropriately. Valid values are:
0 - Do not use shells for connectivity, orientation, or offset
1 - Use only displayed shells for connectivity, orientation, and offset
2 - Use all shells for connectivity, orientation, and offset
3 - Use shells for connectivity only. within the tolerance zone. If useproximity=1, the ordered nodes within proximitytolerance are used to create 1D elements.

Examples

Create 1D elements using lines and assign properties to these newly created elements. Also, update the orientation and offset of these elements using neighboring shells:
*createmark lines 1 1-4
*createelements1d lines mark=1 property=PBARL elemsize=10 elemconfig=bar2 elemtype=CBAR linecomp=1 useshell=1 breakangle=0 biasintensity=1 biasstyle=0
Create 1D elements using lines and proximity tolerance. Also, update the orientation and offset of these elements using neighboring shells:
*createmark lines 1 1-4
*createelements1d lines mark=1 elemsize=10 elemconfig=bar2 elemtype=CBAR linecomp=1 useshell=3 breakangle=0 elemdensity=1 useelemdensity=1 biasdensity=0 biasstyle=0 useproximity=1 proximitytolerance=-1.0
Create 1D elements using nodes and assign beam section to these newly created elements:
*createlist nodes 2 1 2 3 4
*createelements1d nodes list=2 beamsection=Circ elemsize=2 elemtype=CROD elemconfig=rod linecomp=0 useshell=0 breakangle=30 elemdensity=1 useelemdensity=0 biasdensity=0 biasstyle=0

Errors

Incorrect usage results in a Tcl error. To detect errors, you can use the catch command:
if { [ catch {command_name...} ] } {
   # Handle error
}

Version History

2019

2020 - Added new options elemconfig, proximitytoleranceand useproximity. Added new useshell value 3.

2020.1 - Added new option orientvec. Clarified the behaviors for useshell.

2022.1 - Added new optional arguments engineeringconfig and propcardimage.