Developing a Technology Selection Framework for Initial Data Acquisition for HBIM and Digital Twin Creation in Sri Lankan Heritage Sites: A Case Study on Lankathilake Pilimage, Polonnaruwa

Abstract. This research aims to develop and apply a structured technology selection framework for initial data acquisition for Heritage Building Information Modeling (HBIM) and Digital Twin creation in Sri Lankan heritage sites. The study addresses the challenge of selecting appropriate 3D documentation technologies by proposing a transparent and systematic decision-making process. The study employs an Analytic Hierarchy Process (AHP) as its foundational framework. An AHP model was developed, defining a set of criteria (Cost, Geometric Accuracy, Texture Quality, Ground and Aerial Accessibility, Scale) and alternatives (various terrestrial and drone-based scanning and photogrammetry technologies). The framework’s effectiveness was validated through a detailed case study of Lankathilake Pilimage, followed by hypothetical applications for four other representative heritage sites. The AHP model successfully provided a ranked list of technology alternatives. For the Lankathilake Pilimage case study, the AHP results prioritized Drone Photogrammetry as the most suitable method, followed by Terrestrial Photogrammetry and then a combined Drone Lidar and Drone Photogrammetry approach. The application of the framework to other sites demonstrated how project- specific requirements, translated through pairwise comparisons, lead to different optimal technology choices. The AHP framework provides a robust and repeatable methodology for selecting primary data acquisition technology. It effectively incorporates multiple, often conflicting, criteria to arrive at a data-driven decision. This framework is a valuable tool for heritage conservation professionals and researchers, offering a clear path forward for HBIM and Digital Twin projects in Sri Lanka.