Computer modelling of the Han Tomb at Lei Cheng Uk by photogrammetric survey

Abstract

The Han Tomb at Lei Cheng Uk (the Tomb) is one of the important heritage sites found in Hong Kong. It is a four-chambered tomb which is believed to date from the Eastern Han dynasty (25-220AD). The front chamber consists of a square base (2.4mLx2.4mW) and a domed roof (2.9mH). The left, right and rear chambers are of similar structure, each consisting of a rectangular base (4.0mLxl.5mH) and a barrel vault (1.5mH). The purpose of this project, through use of off-the-self hardware and software and employing digital photogrammetry techniques and computer technology, is to record the geometry and shape of the Tomb in the form of digital orthophotos and a wire-frame computer model. Most of the problems in this project originate from the fact that the photogrammetric survey has to be done inside the confined space of the Tomb. Challenges in different aspects of the photogrammetric survey were anticipated. A practical workflow has been devised in this project to overcome various kinds of constraints as well as to ensure that the desirable quality of the final products can be achieved. The knowledge and experience gained from this project are valuable for the recording of other similar heritage sites.