Reflections take place about one of the global X, Y or Z axes, about
a plane at a specified distance down that axis.
To use it:
-
Select the objects to reflect.
-
Define a distance, or use
PICK
to use a
nodal coordinate to define the reflection plane distance.
-
Use
APPLY
to make the reflection happen.
As before the image is drawn showing the new configuration, and you can
accept, reject or repeat the transformation.
-
At present reflection may only take place about global axes.
-
IMPORTANT
: A reflection is
NOT
the same as a rotation by 180 degrees!
Reflection not only moves coordinates, but also reverses the topology
ordering of elements with 3 or more nodes so as to preserve their local
axis systems (and +ve volume in the case of 3D elements). Whereas rotation
by 180 degrees just moves the coordinates. So although the results may
look similar they can have different properties.
-
NEGATIVE SCALE
:
PRIMER treats negative scale (SCX *
SCY * SCZ < 0) as reflection i.e. the topology of elements
is
reversed
. This change was necessitated by the fact that *INCLUDE_TRANSFORM
can only encode a reflection as a -ve scale and Ansys LS-DYNA does reverse
the topology in this case (otherwise it would not work with 3d elements).
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