Online Lecture 16

Research Results
Final Report on Grants-in-Aid for Scientific Research (Basic Research [B]) for the FY 2014.
'Research into the Use of 3D Digital Data to Create Virtual 3D Images to Facilitate
the Study of Kidori (cutting the wooden blocks) and Kiyose (combination of timbers) of Statues,
Dating from the early Heian-Kamakura Periods (8th c.-14th c.)

Research Assignment no. 24320035. Research Period: FY 2012-2014
Research Director: YABUUCHI Satoshi

1. Background to the Commencement of Research

Since 2004, this laboratory, led by the research director, has involved itself in 3D laser scanning and analysis of cultural property sculptures, focusing on those that have been designated national treasures or important cultural properties, pioneering a new field of research in the study of the history of Buddhist sculpture. To date, we have established a new methodology of research with the use of 3D scanning, allowing us to trace the development of the various styles of Buddhist sculpture through the comparison of their exterior forms.
In the process of carrying out this research our projection of 3D digital data has led to the discovery of a new research method. This consists of plotting projections of the 3D data of these statues to create three-dimensional images that present minute detail, indiscernible to the naked eye and unachievable through photography (Fig. 1). In addition, it has become possible to present concrete images of the kidori and kiyose, facilitating minute analysis.
In art history, classification of the methods of kidori and kiyose employed in the production of sculpture provides important clues as to the date of production. Various patterns can be identified in the methods employed in yosegi-zukuri, a unique Japanese method of combining multiple timbers to produce the base for a sculpture, and it is thought that by examining the characteristic of the kidori and kiyose employed, it should be possible to understand the intentions of the sculptor and the conditions under which the work was produced.
This research focused on this point, and proposed to cause stir in the study of Japanese Buddhist sculpture history through ‘the creation of structural plans of kidori/kiyose utilizing 3D digital data’.

 

Fig 1. Standing figure of Komoku-ten (Virupaksa) belonging to Rokuharamitsu-ji Temple, Kyoto. Left: projection view. Right: Kidori (estimated position of main wooden block)

2. Research Objectives
To use 3D laser scanning to obtain minute measurements, combined with supplementary x-ray images; to study and analyze the structure of Buddhist sculpture dating from the Heian to Kamakura periods (794-1333) and to compare and inspect the structure of statues to determine origins and development of both the Jocho-style, which is said to represent the establishment of the first truly Japanese style, and the Kei school, which is said to represent the renaissance of the Kamakura period.

3. Research Methods
Focusing on the Buddhist statues described in the following section 4, (Research Results), we carried out research annually (4 studies per fiscal year, each study researching 1 to 2 statues). Regarding methodology, measurements were carried out using a 3D laser scanner and these combined with supplementary X-ray data. In the final year, the data accumulated from 3D scanning, X-ray images, etc., were combined to create a computer graphic entitled, ‘3D Component Image of Kidori/kiyose Structure'.

4. Research Results
Concentrating on sculptures designated cultural assets but which had not previously undergone 3D scanning, research was carried out on approximately 11 works during the 3 years of the project. The works involved are as follows:

Fiscal year of 2012
・Wooden standing figure of Bishamon-ten [Vaisravana] belonging to Sekkeiji Temple, Kochi Prefecture (X-ray research).
・Wooden figure of Jizo-bosatsu [Ksitigarbha] in half-lotus position, belonging to Tofukuji Temple, Ibaraki Prefecture.
・Wooden seated figure of Yakushi-nyorai [Bhaisajyaguru] belonging to Tokyo branch of Yakushiji Temple (Higashi-Gotanda), Tokyo.
・Wooden standing figure of Miroku-bosatsu [Maitreya], belonging to Todaiji Chushoin Temple, Nara Prefecture.
・Wooden figure of Temple Dog belonging to Nara National Museum.
・Wooden standing figure of Amida-nyorai [Amit?bha] (commonly known as the ‘Looking-back Amida’) belonging to Zenrinji Temple, Kyoto.

Fiscal year of 2013
・Wooden-core dry-lacquer standing figure of Eleven-faced Kannon-bosatsu [Avalokitesvara] belonging to Shorinji Temple, Nara Prefecture.
・Wooden figure of Bosatsu [Bodhisattva] in half-lotus position (said to be of Nyorin Kannon [Chintamanichakra Avalokiteshvara]) that is housed in the main hall of Hobodaiin Gantokuji Temple, Kyoto.

Fiscal year of 2014
・Wooden standing figure of Nyorai [Tathagata] belonging to Kongoshinin Temple, Kyoto

Grants-in-Aid for Scientific Research/Grant
Based on X-ray images of the standing figure of Bishamon-ten [Vaisravana] belonging to Sekkeiji Temple, a student working on her PhD in our laboratory created a replica statue, and using this as reference, we calculated where the work had been split and rejoined, producing a structural plan. In addition, the 3D data and X-ray images of the standing figure of Miroku-bosatsu [Maitreya] belonging to Todaiji Chushoin Temple, was used to create an image showing the estimated position of the main timber (kidori)

mage Showing Estimated Position of the Main Timber
(kidori) Utilizing 3D Data

A majority of the wooden statues created during the late Nara period and early Heian periods were made using the Ichibokuzukuri method, in which the main parts (head and torso) are sculpted from a single block of wood. The wooden statue of the Bosatsu seated in the half-lotus position belonging to H?bodaiin Gantokuji Temple, Kyoto that was used for this research is an example of a work using this Ichibokuzukuri. Created during the late 8th to early 9th centuries, it was found to be sculpted from a single block of wood with just the ends of the hands and feet added (Fig 2).
In the case of the standing figure of a Nyorai belonging to Kongoshinin Temple, Kyoto and dating from approximately the same period, the 3D data and careful visual inspection proved that although it utilizes the same Ichibokuzukuri method, the wood was apparently sculpted at an angle to achieve the forward-leaning pose characteristic of this work (Fig 3). In this way, it can be seen that Ichibokuzukuri statues from this period were not simply sculpted from a vertical block of wood, but the wood was also used at varying angles in order to conform to the movement of the figure.

Fig. 2  Fig. 3

Fig. 2. Statue of Bosatsu seated in the half-lotus position belonging to H?bodaiin Gantokuji Temple. 
Fig 3. Standing figure of Nyorai belonging to Kong?shinin Temple.

Research Results
Using 3D data in this way, it is possible to accurately calculate the combination of the different timbers, facilitating the production of an estimated structural plan and also an ‘estimated structural plan including kiyose and warihagi’ (Figs. 11, 12), which is the first step in creating a statue. Employing 3D computer graphics to produce structural plans in this way facilitates the explanation of complicated structures to third parties and allows us to carry out objective discussions of the structure in a precise fashion.

Fig 4

Fig 5 Fig 6

Fig. 7

Fig 8
Fig 9
Fig 10
Fig. 11  Fig. 12

Fig. 11 Structural Plan of the Ch?shoin statue
Fig. 12 Estimated structural Plan of the Ch?shoin Statue Showing Kiyose and Warihagi

Summary
The use of 3D data facilitates the production of structural plans of Buddhist sculptures of far greater accuracy than was previously possible. This allows us to create clear images of the ichibokuzukuri and yosegizukuri methods, which characterize different historical periods, as well as permitting us to extrapolate the process by which the structure of a particular statue was arrived at, which is an extremely important element. This information can be used to carry out a detailed consideration of the 'chronological sequence of the sculpting', which can be said to be the second characteristic in the structural techniques employed in each step of the production process, including 'timber preparation', 'splitting/joining', ‘interior hollowing', 'finishing', etc., thereby providing important material.


5.Main Published Theses, etc.

Books(Total 3)
'2012 Annual Report', Conservation Course, Sculpture Laboratory, Graduate Department of Conservation, Graduate School of Fine Arts, Tokyo University of the Arts, 2013.
'2013 Annual Report', Conservation Course, Sculpture Laboratory, Graduate Department of Conservation, Graduate School of Fine Arts, Tokyo University of the Arts, 2014.
Planned Publication
'2014 Annual Report', Conservation Course, Sculpture Laboratory, Graduate Department of Conservation, Graduate School of Fine Arts, Tokyo University of the Arts, 2015.

Other
Website, etc.
Conservation Course, Sculpture Laboratory, Graduate Department of Conservation, Graduate School of Fine Arts, Tokyo University of the Arts, Website
http://www.tokyogeidai-hozon.com

6.Research Unit
1. Research Director
YABUUCHI Naoki (YABUUCHI Satoshi)
(12606) Tokyo University of the Arts  (899) Graduate School of Fine Arts  (20) Professor  Researcher ID: 10376931

2. Research Contributors
SOEJIMA Hiromichi
(32635) Taisho University (201) Department of Literature (20) Professor Researcher ID: 20216576

YAMAMOTO Tsutomu
(32632) Seisen University (201) Department of Literature (20) Professor Researcher ID: 00150037

MUKASA Akira
(32618) Jissen Women’s University (201) Department of Literature (20) Professor Researcher ID: 30219844

SUGIURA Makoto
(12606) Tokyo University of the Arts  (899) Graduate School of Fine Arts  (22) Lecturer Researcher ID: 40625589

MASUDA Yoshiki
(12606) Tokyo University of the Arts  (899) Graduate School of Fine Arts  (22) Lecturer Researcher ID: 30625596

SUZUKI Atsushi
(12606) Tokyo University of the Arts  (899) Graduate School of Fine Arts  (28) Assistant Professor Researcher ID: 90620873

Research Results
Appendix:
In addition to the structural plans presented above, this research has also be used to produce the following structural plans that include kidori/kiyose. These diagrams show the structure of the main timbers used in the torso and surrounding elements.

Wooden figure of Temple Dog belonging to Nara National Museum, Nara
Wooden seated figure of Yakushi-nyorai [Bhaisajyaguru] belonging to the Tokyo Branch of Yakushiji Temple (Higashi-Gotanda), Tokyo
Wooden seated figure of Jiz?-bosatsu [Ksitigarbha] with one leg pendant, belonging to Tofukuji Temple, Ibaraki Prefecture

Wooden standing figure of Bishamon-ten [Vaisravana] belonging to Sekkeiji Temple, Kochi Prefecture
Wooden standing figure of Amida-nyorai [Amit?bha], (commonly known as the ‘Looking back Amida’) belonging to Zenrinji Temple, Kyoto
Wooden standing figure of Shaka-nyorai [Shakyamuni] located in the Main Hall of Muro-ji Temple, Nara Prefecture