In GENERAL definition page, the user may define basic information for the current setup, including: title, working coordinate system, tool acceleration time and comment. Figure 8.2.13 illustrates a typical general setup GUI window.
Figure 8.2.13 General definition page
8.2.3.1 TITLE
This function allows the user to enter a title name for the current setup. The user may use any meaningful title to describe the setup.
8.2.3.2 WORKING COORDINATE SYSTEM
This function allows user to set up the working coordinate system. Earlier eta/DYNAFORM versions do not support arbitrary direction as the stamping direction. It is not necessary for the user to transform the forming result to the actual position of the part in the automobile to carry out crash analysis. The user may define a LCS, and use local W direction as the stamping direction. Default coordinate system is global Z direction. If the user needs to define local coordinate system, click the Local CS button to open the WCS dialog box as shown in Figure 8.2.14.
Figure 8.2.14 WCS dialog box
ORIGIN/DIRECTIONS - Define LCS by defining the origin and the direction of coordinate axes. The user may only define W direction to be parallel to local X or Y axis and global X or Y axis.
Origin…: This button allows the user to define local origin. After clicking this button, the INPUT dialog box is displayed. The user may enter point coordinates to define origin or select a node or point by mouse clicking.
U Axis…: This function allows the user to define local U direction. After clicking the button, the DEFINE DIRECTION dialog box as shown in Figure 8.2.15 is displayed.
Figure 8.2.15 Direction dialog box
DIRECTION
Allow the user to define a vector to specify the direction. The starting point of the vector is at the current coordinate system’s origin. The user needs to define the coordinates of the end point of the vector.
- Define the X coordinate of the vector’s end point .
- Define the Y coordinate of the vector’s end point.
- Define the Z coordinate of the vector’s end point.
REVERSE
Allow the user to reverse the current defined direction.
2 POINTS/NODES
Allow the user to select two points or nodes to define a direction.
3 POINT / NODES NORMAL
Allow the user to select three points or nodes to define a direction. This direction is normal to the plane defined by the three points, according to the right hand rule.
ELEMENT NORMAL
Allow the user to use the normal direction of the selected element as the direction.
EXISTED LCS.
Allow the user to select a coordinate from defined LCS as the required direction. After clicking this button, the LCS dialog box as shown in Figure 8.2.16 is displayed. The user may select any LCS and it’s direction.
Figure 8.2.16 Select LCS dialog box
U Axis…: This function allows the user to define local U axis direction. After clicking this button, the DEFINE DIRECTION dialog box is displayed. The user may select any of the LCS in the list.
V Axis…: This function allows the user to define local V axis direction. After clicking this button, the DEFINE DIRECTION dialog box. The operation is the same as in U axis.
W Axis…: This function allows user to define local W axis direction. After clicking this button, the DEFINE DIRECTION dialog box is displayed. The operation is the same as U and V axes.
Note: The user may define U axis and V axis to define LCS. W direction is calculated according to the right hand rule.
W=U×V
The V axis is adjusted again from the W and U axis according to the right hand rule.
V=W×U
The user may only define W axis direction to define the LSC. The U, V direction is defined automatically. This option is useful when the local U and V direction are not important.
DEFINED BY 3 LOCATIONS - Specifies a normal direction by defining three points. This direction is used as the working coordinate system. The interface is shown as in Figure 8.2.17:
Figure 8.2.17 WCS
Near Node: Defines WCS by selecting three nodes.
Near Point: Defines WCS by selecting three geometry points.
Reject Last Node/Point: Rejects last selected node/point.
VIEW DIRECTION - This function allows the user to use current view direction as WCS. Local W axis points to the user from the screen.
EXISTED LCS - This function allows the user to select existing LCS and use the local W axis as WCS as shown in Figure 8.2.18.
Figure 8.2.18 Define WCS by Selecting LCS
8.2.3.3 TOOL ACCELERATION TIME
This function allows the user to specify the tool acceleration time. When defining travel curve in LS-DYNA, the speed ramps up from 0 to the peak value. It is better to define the ramp time to guarantee the stability of calculation. Default ramp time is 0.001 second as shown in Figure 8.2.19.
Figure 8.2.19 Acceleration Time Setup
8.2.3.4 COMMENT
This function enables the use to write comments about the current setup.