Pattern Grouping
Pattern grouping is a feature where you can define a single part of the domain that should be designed in a certain pattern.pattern grouping - free-size optimization.
Planar Symmetry
It is often desirable to produce a design that has symmetry. Unfortunately, even if the design space and boundary conditions are symmetric, conventional free-size optimization methods do not guarantee a perfectly symmetric design.
By using symmetry constraints in free-size optimization, symmetric designs can be attained regardless of the initial mesh, boundary conditions, or loads. Symmetry can be enforced across one plane, two orthogonal planes, or three orthogonal planes. A symmetric mesh is not necessary, as OptiStruct will create variables that are very close to identical across the plane(s) of symmetry.
Uniform Element Thickness
Pattern grouping also provides the possibility to request a uniform element thickness throughout selected components.
This pattern group ensures that all elements of selected components maintain the same element thickness with respect to one another.
Cyclical Symmetry
Cyclical symmetry can also be defined through the use of pattern grouping.
With cyclical pattern grouping, the design is repeated about a central axis a number of times determined by you. Furthermore, the cyclical repetitions can be symmetric within themselves. If that option is selected, OptiStruct will force each wedge to be symmetric about its centerline.