System entities, commonly called coordinate systems, can be defined as rectangular, cylindrical, or spherical coordinate systems. Several systems may be nested. There are two types of system assignments to entities; as a reference system, or as a displacement system. A system may be a reference system, a displacement system, or both.
A reference system is used to define the geometric positions of entities. Entities that can be assigned a reference system include systems, nodes, and loads. By default, each of these entities is defined in the global system with an ID of zero. Entity data is always displayed and reviewed transformed into the global system. When a reference system is deleted, the position of the entity assigned that reference system is maintained relative to the global system in the transformation process. For example, if you define the nodes of a cylindrical structure in a cylindrical reference coordinate system, and then delete the cylindrical reference coordinate system in which the nodes are defined, the model retains its cylindrical shape and also its location in space but is now referenced to the global system.
A displacement system is used to define the nodal degree of freedom coordinate system assigned to a node. The only entity that may be assigned a displacement system is a node. When you delete a displacement system, the nodal degrees of freedom are not transformed to the global system, so all degree of freedom definitions after the deletion of the displacement system are now simply in the global system.
The data names associated with systems can be found in the data names section of the HyperMesh Reference Guide.
The following panels can be used to create and edit systems:
Systems
Solver Card Support for Systems
The supported RADIOSS cards in RADIOSS (Block Format) 100 are listed below. To create these cards, right-click in the Solver browser and select Create Cards from the context menu.
Supported Card
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Solver Description
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Supported Parameters
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Notes
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/FRAME/FIX
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Describes the frames.
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/FRAME/MOV
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Describes the moving frames. Relative motion with respect to a reference frame.
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/FRAME/MOV2
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System definition with Z axis and YZ plane.
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/FRAME/NOD
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Describes the node defined moving frame.
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/SKEW/FIX
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Describes the fixed skew frames.
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/SKEW/MOV
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Describes the moving skew frames.
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/SKEW/MOV2
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System definition with Z axis and YZ plane.
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The Systems panel offers two methods to create local coordinate systems, working with the RADIOSS (Bulk Data), OptiStruct user profile as follows:
Supported Card
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Solver Description
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Supported Parameters
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Notes
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CORD1C
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Defines a cylindrical coordinate system by referencing three grid points. The first point is the origin, the second lies on the z-axis, and the third lies in the plane of the azimuthal origin.
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This type of system is created from the create by node reference subpanel when cylindrical is the chosen type.
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CORD1R
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Defines a rectangular coordinate system by reference to three grid points. The first point is the origin, the second lies on the z-axis, and the third lies on the x-z plane.
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This type of system is created from the create by node reference subpanel when rectangular is the chosen type.
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CORD1S
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Defines a spherical coordinate system by reference to three grid points. The first point is the origin, the second lies on the polar axis, and the third lies on the plane of the azimuthal origin.
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This type of system is created from the create by node reference subpanel when spherical is the chosen type.
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CORD2C
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Defines a cylindrical coordinate system by reference to the coordinates of three grid points. The first point defines the origin. The second point defines the direction of the z-axis. The third lies in the plane of the azimuthal origin.
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This type of system is created from the create by axis direction subpanel when cylindrical is the chosen type.
Various combinations of axes and planes are allowed to be indicated in the create by axis direction subpanel, but will write out the appropriate coordinates to define the z- axis and the x-z plane.
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CORD2R
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Defines a rectangular coordinate system by reference to the coordinates of three points. The first point defines the origin. The second defines the direction of the z-axis. The third point defines a vector, which, with the z-axis, defines the x-z plane.
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This type of system is created from the create by axis direction subpanel when rectangular is the chosen type.
Various combinations of axes and planes are allowed to be indicated in the create by axis direction subpanel, but will write out the appropriate coordinates to define the z- axis and the x-z plane.
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CORD2S
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Defines a spherical coordinate system by reference to the coordinates of three points. The first point defines the origin. The second point defines the direction of the z-axis. The third lies in the plane of the azimuthal origin.
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This type of system is created from the create by axis direction subpanel when spherical is the chosen type.
Various combinations of axes and planes are allowed to be indicated in the create by axis direction subpanel, but will write out the appropriate coordinates to define the z- axis and the x-z plane.
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CORD3R
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Defines a rectangular coordinate system by reference to three points. The first point is the origin, the second lies on the x-axis, and the third lies on the xy plane.
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This type of system is created from the create by node reference subpanel when rectangular is the chosen type.
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CORD4R
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Defines a rectangular coordinate system by reference to the coordinates of three points. The first point is the origin, the second lies on the x-axis, and the third lies on the xy plane.
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This type of system is created from the create by axis direction subpanel when rectangular is the chosen type.
Various combinations of axes and planes are allowed to be indicated in the create by axis direction subpanel, but will write out the appropriate coordinates to define the z- axis and the x-z plane.
Editing the card image for a CORD2R will allow users to define a CORD4R.
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The coordinate systems are defined from the Systems panels. A system can be exported as a *SYSTEM or *TRANSFORM card depending on the nodal assignment of the system. To export an *ORIENTATION card it is required to enable the option in the card image of the system card.
The following Abaqus (system) keywords are supported:
Supported Card
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Solver Description
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Supported Parameters
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Notes
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*ORIENTATION
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Define a local axis system for material or element property definition, for kinematic coupling constraints, for free directions for inertia relief loads, or for connectors
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LOCAL DIRECTIONS
NAME
SYSTEM
DEFINITION = COORDINATES
/NODES
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The *ORIENTATION card needs a name in Abaqus. Since systems do not have a name, a name needs to be entered in the system card image. The restriction of one system per system collector has been removed with version 10.0 – SA1-130.
DEFINITION = NODES option with only two nodes is converted to DEFINITION=COORDINATES upon import from an input file.
*ORIENTATION with SYSTEM = Z RECTANGULAR is converted to RECTANGULAR upon import from an input file.
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*SYSTEM
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Specify a local coordinate system in which to define nodes
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Whenever a system is assigned to nodes with the set reference option from the Systems panel activated, a *SYSTEM card is exported before the node block of its assignment.
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*TRANSFORM
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Specify a local coordinate system at nodes.
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TYPE
NSET
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If assigned to individual nodes, on export each *TRANSFORM card creates references to an automatically generated *NSET card. This *NSET card is followed by the list of the nodes that are assigned to the coordinate system with the set displacement option.
Systems can be assigned to node sets with the same assignment procedure.
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Supported Card
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Solver Description
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Supported Parameters
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Notes
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LOCAL
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Defines a local coordinate system by location and orientation.
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KCN, KCS, XC, YC, ZC, THXY, THYZ, THZX, PAR1, PAR2
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Even if KCN>10, 10 is added to the current value.
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LOCAL
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Defines a local coordinate system by location and orientation.
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R5.0, Type, NCSY, CSYTYP, VAL1, VAL2, VAL3
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Type = PRM not supported
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The systems cards can be previewed, but not edited.
Supported Card
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Solver Description
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Supported Parameters
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Notes
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*DEFINE_COORDINATE_
NODES
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Define a local coordinate system with three nodes.
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*DEFINE_COORDINATE_
SYSTEM
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Define a local coordinate system with three points.
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*DEFINE_COORDINATE_
VECTOR
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Define a local coordinate system with two vectors.
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Supported Card
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Solver Description
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Supported Parameters
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Notes
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CORD1R
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Defines a rectangular coordinate system using three grid points.
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N/A
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CORD2R
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Defines a rectangular coordinate system using the coordinates of three points.
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N/A
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CORD1C
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Defines a cylindrical coordinate system using three grid points.
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N/A
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CORD2C
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Defines a cylindrical coordinate system using the coordinates of three points.
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N/A
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CORD1S
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Defines a spherical coordinate system by reference to three grid points.
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N/A
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CORD2S
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Defines a spherical coordinate system using the coordinates of three points.
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N/A
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Supported Card
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Solver Description
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Supported Parameters
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Notes
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FRAME /
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Local frame definition - system collectors
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If there is a $HMMOVE directive found for a system and that system collector exists in the model, the system is placed in that collector. Otherwise, a separate system collector is made for the frame.
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FRAME /
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Local frame definition - systems
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NAME, NODS
Frame Update Options (Initial Orientation Rotates with Attached Entity, Fixed Orientation, Self-Rotating Orientation)
Frame Axis Definitions (Via 2 Vectors, Via 3 Nodes)
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If a base node is not given, system is created at the global origin 0, 0, 0. In case of frame definition with nodes, system is created at the first node.
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TRSFM /
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Select elements and nodes subject to transformation
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NAME, Selection, Keyword, D, X, Y, Z, N1, N2
NumDatalines
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See Also:
Include Files
System Collectors
