Remote Sensing Data as Basis for the Modelling and Reassembly Of Dismantled Heritage Structures

Abstract

<p><strong>Abstract.</strong> Remote sensing techniques are invaluable for the documentation and preservation of built heritage. The techniques facilitate fast documentation of highly complex heritage structures with improved accuracies. Furthermore they improve the degree of detail substantially. This is extremely useful for the restoration of collapsed elements or the reassembly of dismantled structures. These entities are often challenging to puzzle back together. Moreover, the differential settlements of the elements over time heavily influence the relative position and orientation of the remaining pieces, further complicating the reconstruction. Digital modelling solutions with a 3D model of the current situation as take-off, are desperately needed by the industry to tackle the present obstacles. In this work, a framework is proposed that facilitates a more accurate reassembly of dismantled heritage elements. It consists of three major phases starting with the accurate recording of the current situation as well as the preserved components. Subsequently, the new design is dititally modelled, reducing the necessary time for the reassembly of the structure, which is the last step in the rebuilding workflow. The presented framework allows for an efficient and comprehensible reconstruction of the structure. A key aspect in the approach is the detection of missing components and the estimation of their dimensions for the production of accurate replicas. The potential is showcased by means of two case studies on the reassembly of flying buttresses and rib vaults of the Saint-James church in Leuven, Belgium, which is currently undergoing major stabilisation works. The presented approach allows heritage experts to gain better oversight over their reassembly project and work more efficiently.</p>

Suitability of Automatic Photogrammetric Reconstruction Configurations for Small Archaeological Remains

“…Both were chosen for their intuitive software interfaces and available documentation about use. The present approach is significant for three main reasons: aids in the reconstruction of small archaeological parts for documentation purposes [52]; helps assemble dismantled heritage elements and/or missing parts [29]; and generates didactical models for the acquisition of competences in an e-learning context [53] and can be included in products like augmented or virtual reality (AR/VR) applications for awareness-raising [6].…”

“…Moreover, the positioning of the control points and their marking in the image are also critical steps to assure the accurate reconstruction with metric units. The latter is significant for the assembly of dismantled heritage elements and/or missing parts [29]. To obtain the complete geometry of an object (360 • image acquisition), it is necessary to take shots around it according to a specific path or, alternatively, keep the camera fixed and rotate the object at predefined angle steps [30,31].…”