How we understand Geometry

For the optimisation we define different areas of the geometry. These are mainly Design and Non-Design Spaces.

The Design Space is the most important space and complies with the imported/created solid CAD geometry. It includes any space where material is allowed to be or has to be, to provide maximal freedom for the algorithm. If the Design Space is limited, so is the optimisation algorithm and the optimisation potential is reduced.

The Non-Design Space contains the necessary geometries of the part. Any part for which you need a clearly defined geometry should be a Non-Design Space. To create Non-Design Spaces the geometry needs to be either split into cells or a constraint is applied to a surface, edge or point which automatically creates a Non-Design Space for this geometry. Cells are partitions of the Design Space. They can be created with the split tool, directly in the Non-Design selection tool or with a Boolean operation using two or more solids.

Void Spaces are spaces within your part where no material is allowed to be and free space for example for other parts of the assembly is needed. These spaces need to be cut out of the Design Space with a Boolean operation.

Intersections are necessary after each optimisation to get the defined surfaces of the Non-Design Spaces. These defined shapes are needed for example for the post processing of the manufacturing process. The intersection is done automatically for every iteration.

To realize a post processing of additive manufactured parts an Manufacturing Allowance needs to be considered for the functional surfaces. This needs to be added to the Non-Design Spaces and therefore to the Design Space before an optimisation is started. Afterwards it is very complicated and time consuming to add such an offset to the result file.

Tip: Avoidance of stress rising on Design Space boundaries. Sometimes it is useful to reduce the Design Space a little bit for the optimisation by subtracting an offset. The optimisation is carried out with this reduced Design Space. However, the intersection afterwards is done with the originally defined Design Space in order to avoid sharp edges and thus stress risings. This way you avoid stress risings on the boundaries after you have combined your optimisation result with your original Design Space.

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Design Space Generation - Bookshelf