Tochigi Museum surveys cultural assets with FARO Laser Scanner Focus3D
"By scanning the Stone Buddha using the FARO Laser Scanner Focus3D, we have unexpectedly discovered clear features of the arms, which was not discernible with the naked eye," said Mr. Shuichi Morishima, Chief of Humanities Division, Tochigi Prefectural Museum.
The site in focus is the Sanuki Stone Buddha in Shioya, Tochigi Prefecture. Towering at a height of 64m, against a large mass of rock wall near the bank of Kinugawa River, is a rock-hewn Buddha. As a result of how the light hits the rock surface, only some parts of the Stone Buddha can be seen with the naked eye. However, by viewing the Stone Buddha through the point cloud data that is obtained by the Focus3D, the natural features of the carving become much more visible, since the 3D data is unaffected by sunlight or shadow.
Mr. Morishima explained, "This Stone Buddha was said to be an art piece of the Heian or Kamakura Era, circa 12th and 13th century. Using the Focus3D, we were able to determine previously unknown features of the Stone Buddha. As a result, we now understand that the work possibly dates further back in history than what was initially thought, a result we attained only because of the 3D Laser Scanner."
Museum Exhibits that Move with the Times
Tochigi Prefectural Museum is an all-rounded museum that is involved in a variety of academic disciplines, from earth science to history. Its principal exhibits are aimed at providing a stereoscopic understanding of history – for instance, the relationships that exist between extinct animals and stoneware of a certain time period in the past. The museum does not just offer visitors a glance at exhibits enclosed in glass cabinets. Instead, it aims is to be an institution that fosters visitors’ understanding, by allowing them to touch and hold artifact models or replicas (e.g. clay figurines and stoneware). In order to achieve the goal of having such displays, Tochigi Museum introduced the Focus3D into its exhibit preparations workflow in July 2015.
"We believe that point cloud data can help visitors to better understand large-scale, outdoor exhibits such as the Stone Buddha and other buildings," said Mr. Morishima. "Due to budgetary constraints, we decided not to splurge on 3D scanners that can cost up to several hundred thousands of U.S. dollars each. The choice of the Focus3D was a much more affordable one."
Several years ago, Mr. Morishima visited Nara National Research Institute for Cultural Properties and observed the use of the Focus3D there. The Museum was encouraged to make use of the Laser Scanner as well, especially after learning of the many case studies of Focus3D successes on Nara National Research Institute’s website.
Digital Archiving – Historical Building Features & Ancient Tomb Interiors
Since introducing the Focus3D, Tochigi Museum plans to use the device in various settings to record cultural assets and conceptualize exhibits. One of these applications is the conservation of features on a historical building through digital archiving in 3D data.
Mr. Morishima explained, "Increasingly, we are getting requests from corporations that are keen to preserve the data of their old buildings, which may have been built when their firms were first established. When it comes to the physical preservation of old buildings, there are several critical concerns such as limitations on efficient land use and cost of management or maintenance. By digitally archiving a building with a 3D scanner, the point cloud data can reproduce the original features of a building, and the information can still be used long after demolition. With this data, one can in fact simulate a walk-through of the building in life size using a head-mounted display."
While scans are being performed, the Focus3D also captures photographs of the scene, which later allows users to view point cloud data in color. This facilitates Tochigi Museum’s exhibition planning purposes, given that colors, textures, building shapes, and sizes are all preserved with one touch.
Apart from preserving buildings, Tochigi Museum has found the Focus3D useful for capturing the interiors of ancient tombs and stone chambers. While the museum may have some drawings and photographs in its research archives, these records are not ideal, as there is parallax at the edge of photographs and manual drawings may lack in detail. With the Focus3D, Tochigi Museum can now archive tombs in point cloud data, significantly enhancing the detail and quality of the archive, and providing exact dimensions and shapes of pertinent structures for future reference.
Easy-to-use Device, Suitable for Non-specialist Staff
The scanning process for the ancient tomb of Kurumazuka involved the positioning of the Focus3D in several locations – across the mound and in the interior of the stone chambers – to capture multiple sets of point cloud data before stitching all the obtained data into a single file.
Mr. Morishima explained, "The SCENE software designed for the Focus3D integrates the point cloud data, and this process is usually performed by our museum staff. The task is especially easy to master, even for anyone who is not a specialist in terms of 3D scanning!" He added, "The Focus3D is also compact and lightweight, allowing anyone to easily transport to the mountains, for example, or to place on slopes without having to worry that it may topple over."
In future, Tochigi Museum plans to make use of the point cloud data of cultural assets to create 3D-printed models and replicas. For example, the team wants to capture in point cloud data, the lotus pattern carved on the edges of ancient roof tiles. The pattern can then be scaled down and deepened accordingly, as a preparatory step for 3D printing. Using molding techniques, the team can in turn produce plaster models of the original pattern for visitors to paint on at special events in the museum.
When equipped with a 3D laser scanner like the Focus3D, the museum can record valuable cultural assets and buildings with a high degree of accuracy. These records can be used for new attractions involving eye-catching exhibits of historical and cultural value, which can help to appeal to more visitors.