Mapping between Design and Assembly Structures

As already mentioned the design structure is built up in parallel with the creation of the hull structure (the panels) even if the block structure may be established with an otherwise empty model. This structure can be changed and further refined as the penetration of the design proceeds.

The complete assembly structure can in principle be created at the start of a project before any modelling work has been done. However, before the assembly structure can be populated by parts these must have been generated and inserted in the design structure.

The mapping between the assembly structure and the design structure is normally made via the Assembly Planning application. It creates bi-directional pointers (via names) between the nodes of the assembly tree and the parts of the design structure. It should be noted that these links are to the normally implicit parts in the design structure and not the extracted parts ready for production.

This mapping is arbitrary and is always on part level. Parts from a certain panel may be assembled in any assembly on any level and a certain assembly may contain parts from several different panels that may be located in different (design) blocks. As an example all the parts of a panel with the exception of a few brackets may be welded together in a low-level sub-assembly. The brackets may be welded several stages later in the assembly process, for example, when two main sections are welded together.

The figure in the next page illustrates a possible mapping between a design structure and the assembly structure that is based on the same model. Each dot in the panel boxes of the design structure represents a part and the lines with errors represent the links between node in the assembly tree and the parts.