WissKI 3D Repository as a tool for the preservation and exploration of 3D models of cultural heritage

Exploring 3D models requires accessible digital 3D assets suitable for 3D viewing tools. Despite increasing interest in 3D models within the cultural heritage sector, standards for publishing 3D models remain unreconciled. It compels cultural institutions to adhere to general guidelines inadequate for 3D model exploration on the web. This trend is culminating in a scenario where cultural and scientific institutions increasingly depend on commercial, private repositories, which lack assurances regarding the long-term sustainability of the stored data. Sketchfab, a platform with over 100,000 heritage models by 2019, is a current leader in exploring cultural heritage models online. However, there is growing controversy around the platform in academia, especially following its acquisition by Epic Games in June 2021. In light of the aforementioned considerations, it becomes critically important to establish an alternative environment for the publication of 3D models of cultural heritage, which endeavours to fulfil contemporary requirements for publishing and extracting data on the web. The WissKI-based 3D Repository was developed to address these challenges, featuring an integrated 3D viewer and aligning with the FAIR Principles and Semantic Web approach. the WissKI 3D Repository, hosted by the Hochschule Mainz, aims for sustainable accessibility and archiving cultural heritage 3D models. This article presents the technological strategies employed in constructing a repository as a component of the first phase of the project ‘DFG 3D-Viewer: Infrastructure for Digital 3D Reconstruction’. It employs Drupal and WissKI for data management, facilitating semantic relationships and storage as a triplestore to establish an open platform for efficient 3D data publishing. The study critically examines existing solutions for metadata-based documentation of 3D models and explores documentation frameworks in various 3D repositories. This analysis facilitated a new metadata proposal encompassing mandatory and optional fields. The processed schema was transferred into a data model employing the CIDOC CRM-referenced application ontology of OntSciDoc3D. Furthermore, the significance of controlled vocabularies in the system is highlighted, exemplifying their application. The article also introduces the internally developed 3D viewer, outlining its functionalities and operational mechanisms. The paper culminates with an overview of practical tests conducted in two domains: the archiving of 3D models by cultural heritage 3D practitioners and the dissemination of 3D models through web publication in higher education, specifically in courses on digital reconstruction. Participants of each test group shared their experiences through a concluding survey. The feedback from respondents offers an evaluation of the repository in terms of practical applications and user experience (UX) design. It allows the identification of current system limitations and indicates future developmental directions.