Curating Architectural 3D CAD Models

MacKenzie Smith's article presents MIT’s FACADE (Future-Proofing Architectural Computer-Aided DEsign) research project as an attempt to determine how to preserve and provide access to 3D CAD digital records. The digital curation project includes working with three architectural firms to determine their workflow, usage, and expectations about archival preservation of their digital design records. Traditionally, architectural archives have included records about the design of architectural projects, as well as firm records that support the creation of buildings. Numerous documents are generated through the process of architectural design and these records are now largely digital born – email correspondence, digital photography, 2D CAD renderings, and 3D CAD models, to name a few. Architects generally use proprietary software to create many of their design. Most of these files are easily migrated or converted to standard formats, such as PDF or JPEG. The problem arises when trying to preserve or access 3D architectural models, created using proprietary software in non-standard formats, which cannot be easily migrated or converted.

This presents a major problem for libraries, archives, and museums whose goals would include providing access to the digital records, but would not have the funding to support the ownership and maintenance of proprietary software systems, especially when the software used to create the documents rapidly changes. The FACADE project looked at strategies for exporting files and creating standard formats. This required expertise in both the CAD software and the underlying data, which many librarians or archivists at repositories would not have. The hope is that this process will become more automated over time.

One of the primary issues is how to connect the various records created within context of the design process. The 3D model is most valuable when viewed in relation to other drawings, photographs, and project correspondence. To this end, they have established a “Project Information Model” which will collect 3D model data and connect it to other project records. They have created a prototype for open source software that will assist curators in creating metadata.

The FACADE project web site includes further information, including a final report on the project. The final report outlines four versions in different formats that will be used to preserve the 3D CAD models.

1. Original (the originally submitted version of the CAD model)
2. Display (an easily viewable format to present to users, normally 3D PDF)
3. Standard (full representation in preservable standard format, normally IFC or STEP)
4. Dessicated (simple geometry in a preservable standard format, normally IGES)

This project was funded by a two-year grant from IMLS. The project predominantly set out to conduct research on the best methods and practices for curating 3D CAD models. There are still many research questions to be addressed, such as those pertaining to privacy and copyright of the data.