Assessment of laser-based reverse engineering systems for tangible cultural heritage conservation

Abstract

The process of acquiring the geometry and shape of a part and reconstructing its digital model is known as reverse engineering (RE). This approach is usefully employed in fields as diverse as product design, design modification, geometrical inspection, worn or damaged parts repair or remanufacturing, when physical object drawings, documentation or computer models are not available. The recent scientific and technical developments of RE methods and tools have broadened the possibilities of applications in the field of cultural heritage conservation ranging from reproduction (e.g. via rapid prototyping), maintenance (e.g. computer-aided repair), multimedia tools for education and dissemination (e.g. virtual museums), to artefact condition monitoring (e.g. computer-aided inspection) and many more. The first stage of the RE procedure is digital data acquisition that can be carried out by means of several different tools. The selection of the 3D digitising system is crucial as it directly affects the process time and the quality of the point cloud, which determines the final digital model. In this research work, following the EC FP7 open topic on ‘Equipment assessment for laser based applications’ compiled in Horizon 2020, two non-contact laser-based RE systems, respectively, based on a coordinate measuring machine and a portable 3D scanning equipment, are utilised for the digitisation and reconstruction of a free-form tangible cultural heritage artefact to comparatively assess the RE system's performance in terms of process time, accuracy and ease of use.

Keywords:

• reverse engineering
• laser scanning
• cultural heritage
• coordinate measuring machine
• portable scanning system

Acknowledgements

This research work was carried out within the framework of the Executive Program of Scientific and Technological Co-operation between Italy and China, Ministry of Foreign Affairs, under the Significant Bi-Lateral Project on: Reverse Engineering Methods for 3D Digital Reconstruction, in collaboration with the Tienjin University, Tienjin, China (duration: 2010-2013). The Fraunhofer Joint Laboratory of Excellence for Advanced Production Technology (Fh - J_LEAPT) at the Department of Materials and Production Engineering, University of Naples Federico II, is gratefully acknowledged for its support to this research activity.