村山 英晶

I started my research carrier in fiber optic sensors from 1995 at the University of Tokyo. In the master’s course I applied fiber optic sensors to structural monitoring of a steel ship. I dedicated my doctoral work to a research project of structural health monitoring in which distributed fiber optic sensors based on Brillouin scattering were applied to strain monitoring of International America’s Cup Class yacht structures. This project was managed by me and implemented with Nippon Telegraph and Telephone Corporation (NTT) and GH Craft which is Japanese manufacture of composite structures. At the same time I was working as a technical member of Nippon Challenge Inc. which entered America’s Cup 2000 and made two racing yachts for the competition. For Nippon Challenge I carried out structural analysis by finite element method (FEM) and engaged in manufacturing the ship hulls and some parts of the yachts. After I completed my doctorates, I joined NASDA as a researcher. I was a member of HOPE-X project team which was developing a Japanese Reusable Launch Vehicle (RLV) in NASDA and I was involved in developing the low-cost manufacturing technology and implementation of structural tests for a prototype fuselage made of CFRP. In May 2003 I moved to the University of Tokyo to be a lecturer of School of Engineering. My work here has been mainly focused on structural health monitoring, fiber optic sensors and composite structures. In the study of fiber optic sensors I have developed a distributed sensing technique based on optical frequency domain reflectometry with fiber Bragg gratings (FBG) and achieved the high spatial resolution of less than 1 mm. JAXA and several companies have joined developing a practical system and application of this sensing technique. Since 2007 I have also managed several projects on structural health monitoring of civil structures, such as bridges and railway structures, and on monitoring system for river flow condition by using fiber optic sensor networks. Composite materials and lightweight structures are essential and lasting research topics of the laboratory to which I’m belonging (艤装研究室: Giso laboratory). From 2001 to 2003 I had a research grant to study 3R (reduce, reuse, recycle) technology for polymer composite materials as using IT based on RFID technology. From 2007 to 2011 I was involved in a research project related to rotor blades of an ocean current/tidal power generation system and studied on passive pitch control blades made from composites. Since 2007 I have worked with collaborators to develop composite marine propellers. I have been in charge of evaluating fatigue strength of carbon fiber reinforced plastics (CFRP) and have studied on design technique. By a collaborator a CFRP marine propeller was firstly installed on the main propulsion system of a merchant vessel in May 2014. In addition, since 2003 I have studied on micro aerial vehicle (MAV) and autonomous surface vehicle (ASV) mainly for pedagogical projects.
I classify my research as follows:

A. Study on Structural Health Monitoring and Management (1995 - )
I am aiming for the realization of a structure which can monitor its own condition and integrity and then call for suitable operation or maintenance works. This kind of structures needs nerves and a brain to identify the condition and make a right decision as if a human-beings do so. To give senses and perception to the structure, I am studying on mainly fiber-optic sensing technology and developing the fiber sensor network system. Also I am developing analysis methodologies to determine the overall deformation and load based strain data obtained from limited locations. The purpose of this study is to improve reliability and safety of space transportation system, aircraft, ship, civil structures and so on.

B. Development of Distributed Fiber Optic Sensors (2002 - )
I have developed a fiber-optic distributed sensing system with the high spatial resolution. Its resolution is less than 1 mm and it can easily map the strain and temperature profile along the sensing fiber with fiber Bragg gratings (FBG). This sensing system based on optical frequency domain reflectometry (OFDR) can be applied to precise and global strain and temperature measurements in various structures. Now I’m aiming to increase in performance of the sensing system about the measurement speed, the measurement range and the simultaneous measurement technique rather than the spatial resolution, in order to enhance its applicability.

C. Study on Fiber Optic Sensor Network (FOSN) for Disaster Prevention (2007 - )
I am aiming for the realization of FOSN to eliminate or decrease the risk caused by natural disasters. I established a nonprofit organization with some companies in 2007. It is “Photonic Sensing Consortium” and it has about 20 company members. I have leaded some projects: development of FOSN for disaster prevention information system and SHM of railway structures with a Japanese railway company, development of OFSN for river management supported by Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and development and operation of condition monitoring system for bridges and so on.

D. Marine Composite Structures (2007 - )
Composite materials have advantages in the marine field thanks to the higher specific strength/stiffness and the corrosion resistance. Composites have been generally used to the hulls of boats. I’m aiming to enhance the performance and environment adaptability of vehicles and structures in ocean by applying composites to them. I developed the technologies for the passive pitch control blades of an ocean current/tidal power generation system in the project between 2007 and 2011. Marine composite propellers have also been developed for merchant vessels in the project with the companies from 2007. In this project I’m aiming to develop technologies to enhance the strength of composites for marine propellers and to design the higher performance propulsion system.

E. Study on Autonomous Surface Vehicle and Micro Aerial Vehicles (2003 - )
In pedagogical projects in the university I have developed autonomous surface vehicles (ASV) and micro aerial vehicles (MAV) with students. In 2013 and 2014 the professors of KTH Royal Institute of Technology in Stockholm and I organized the projects in which the student of KTH and the University of Tokyo made the concepts and designs of ASV and manufactured the boats to participate in the races, together. In these projects I’m learning and aiming to build a methodology to let engineering students be professional engineers.