Main Help → All Commands → FEA Mesh / MPM Grid and Material Points → Origin
The Origin
command has two functions depending on whether it is used in a BMPRegion
command or if it is used outside that command in FEA calculations.
For FEA analysis (and outside any BMPRegion
command), the Origin
command is used to set the origin for entry of key points using the (style)
="polar" option. The format is
Origin (xo),(yo)
where (xo,yo)
are the coordinates of the new origin (or R
and Z
coordinates if axisymmetric) (in length units). This origin is only used when using the "polar" mode for entering key points. The default origin is (0,0).
BMPRegion
commandWhen used within a BMPRegion
command for either MPM or FEA, the Origin
command is used to map the image in the associated BMP File to the background MPM grid or the existing FEA mesh. Its format is
Origin (xo),(yo),<(zo)>,<(flip)>
where:
(xo,yo,zo)
are the coordinates of lower-left corner of the image in the BMP File (in length units). The (zo)
value is only needed for 3D MPM models; it is ignored for all others. In axisymmetric calculations, (xo,yo)
gives the R
and Z
coordinates of the origin.(flip)
is equal to "yes", the origin will move to the upper-left corner of the image with y increasing in the downward direction and x increasing to the right. This change will flip the image in the y direction in the MPM analysis compared to the image graphics. To use the optional parameter in non-3D calculations, you have to enter a dummy (zo)
value for parameter alignment.The default origin (if none is specified) is (0,0,0). See BMPRegion command
for details on using BMP files to create material points of FEA elements.