JSPS Quarterly
No.47 2014 spring

Research and Life in Japan by a JSPS Fellow (29)

Hailing from Bulgaria, Dr. Vladimir Konstantinov Kotev has from October 2011 been conducting research with his host researcher, Dr. Tetsuya Mouri, in the Faculty of Engineering at Gifu University under a JSPS postdoctoral fellowship. After obtaining his PhD from the Institute of Mechanics, Bulgarian Academy of Sciences and while working there as an assistant professor, he heard about Dr. Mouri's laboratory from his colleagues and decided to ask Dr. Mouri to host him.

- What are you currently researching under your JSPS fellowship?

I am working on developing a compact, patient-safe and easy-to-use robotized system for orthopedic surgery. Our goal is to develop a robotized system for bone drilling and cutting procedures in order to avoid problems incurred in free-hand operations and to reduce the procedure time as much as possible. The system consists of two hand-held executive modules for drilling and cutting, respectively. In our robotized system, drilling and cutting conditions automatically change in line with bone density. The system can also monitor time, velocity, resistant force, penetration depth, and temperature during the procedure, which can be beneficial for surgeons. I have had meetings with surgeons at Gifu University Hospital, and they have given me valuable help in conducting my research.

- How did you become interested in your research field?

As a mechanical engineer, I have always been interested in the design and dynamical modeling of mechatronic systems and robots with biomedical applications. My interest in this field started when I was a master's student, and as a doctoral student I continued to apply my knowledge of mechanics, design and control to bioengineering and robotics. Now, I want to further advance my research in areas of robotics and biomechanics, because I think that robots will be increasingly engaged with humans in the future by assisting and serving them and altering their environment.

- How did you get to know your Japanese host researcher?

My colleagues at my institute in Bulgaria have had a long and beneficial cooperative relationship with the Kawasaki and Mouri Laboratory at Gifu University. So I had many discussions on research work in the laboratory with them. One of my colleagues, who had joined the Kawasaki and Mouri Laboratory under a JSPS Postdoctoral Fellowship, told me about his experience in it. Moreover, I browsed the laboratory's website and was highly impressed with the richness of its research portfolio and scientific accomplishments. I was especially attracted by its innovative and cutting-edge research on the design and control of robotized hands, prosthetic and rehabilitation robots as well as virtual reality and haptic human interface. So I made contact with Prof. Mouri and sent him my research plan, and was very grateful that he agreed to host me. After that, I applied for a JSPS Postdoctoral Fellowship and fortunately was awarded one. Under it, I have found that JSPS provides excellent conditions for conducting research and living in Japan.

- Besides working with Dr. Mouri, are there other reasons that you chose Japan to pursue your research?

As is well-known, Japan is famous for its advanced technology and scientific achievements in various fields. Japan is also a leader in the production of high-quality machines, electronics, computers and robots. Upon graduating from high school, I read some papers written by Japanese researchers, which sparked my interest in Japan. I wanted to get some experience in that environment. Moreover, I thought that Japanese universities offer excellent study conditions along with an opportunity to conduct research. I am very happy that my dream could be realized. Besides the scientific aspects, I wanted to get to know the Japanese people and experience the Japanese lifestyle and culture.

Dr. Vladimir Konstantinov Kotev

JSPS Postdoctoral Fellow, Faculty of Engineering, Gifu University, Japan, 2011-2013

Assistant Professor, The Institute of Mechanics, Bulgarian Academy of Sciences (BAS), Bulgaria, 2009-2011

Ph.D. (Biomechanics), The Institute of Mechanics, BAS, Bulgaria, 2008

M. Sc. (Mechanical Engineering), Technical University of Sofia, Bulgaria, 2002

- Now that you've been there for a couple of years, what is your impression of your host institution?

This laboratory advances top-level innovative research on robotics in various areas such as robot hands, prostheses controlled by biological signals, rehabilitation systems, virtual reality, and haptic interface. It has even developed a tree-pruning robot. Being very famous all over Japan, the laboratory has allowed me to meet many robotics researchers who know Prof. Kawasaki and Prof. Mouri and their work. They publish and exhibit their research in mostly top-level conferences and journals. As both professors have a wealth of experience in the area of robotics, one can learn much from them. On another plane, I also enjoy having interesting discussions with the students in my lab. As they are very industrious, intelligent and motivated, I believe that the students are truly inspired by their work.

- Generally speaking, what is your impression of Japan's research environment?

I have been happy to have the chance to visit some other laboratories and to attend exhibitions and conferences where I could meet other researchers and get familiar with their work. My impression is that Japanese laboratories are well-equipped with modern technologies and that they advance innovative research with mostly practical applications. The students and staffs are also very motivated and they work hard to achieve the highest quality of research. As Japanese universities and institutes provide an excellent working environment, it is not surprising that many foreign researchers choose Japan to conduct their research.

- So far, what has your research achieved under the JSPS fellowship?

I am conducting research related to the modification and improvement of a hand-held orthopedic robotized module named DORO. So far, we have designed a bone-drilling module, named ODRO, that drills at a preliminary depth and detects bone breakthrough. One of the advantages that we have built into ODRO is that it can be used without a navigation system. Now, I am working on the development of a robotized module, OCRO, used for bone-cutting procedures. OCRO is intended to operate at a preliminary setting of depth and stop automatically after the cutting process is completed. It is also being built to perform cutting with appropriate thrust force and feed rate based on variable bone density. I have had the chance to discuss my research with medical doctors and medical robotics researchers, and they recognize the advantages of my research particularly with regard to patient safety. We have presented the results of our work in scientific journals and at international conferences.

- What do you do outside your research work?

I like riding my bicycle and going for walks around the city. I also like meeting the local people and talking with them. Moreover, I have a Japanese class that I attend every week. Especially challenging for me is writing Japanese letters and words. In addition, I am really keen on visiting traditional Japanese houses, temples, and shrines as well as historical and science museums. Also, I love Japanese gardens, parks and castles. I am really happy that I have opportunities to travel to places of interest here and there around Japan. Whenever I have free time, I go to visit a new place and eat the local food, such as udon, soba, miso soup, okonomiyaki, and of course sushi.

- What do you think of life in Japan – its culture and customs?

For me, Japan offers a wonderful mixture of the ancient and modern. On one hand, the Japanese observe traditions, practice ancient rituals and hold festivals. They have strict rules about their traditional clothes and food. On the other, they love modern technologies and their lives are very much influenced by the modern wonders of the world. It is interesting how well the old and modern stand side by side in harmony. In fact, it is its harmony that I particularly like about the Japanese lifestyle. I am also impressed by the people's modesty and respect for each other. The Japanese are very kind-hearted and honest, and they always try to help. I find them to be very understanding of people from different cultures and religions.

- Before coming to Japan, what kind of image did you have of the country? Has your perception changed?

Before I came here, I mainly knew about Japan from what I had read in books or seen on TV. I basically knew Japan for its cars, machines and technologies, and martial arts. I bought some products made in Japan, which gave me some affinity for the country. Now, I am happy that I have had the chance to learn more about Japanese history, traditions, culture and music. Living in Japan has given me a deeper knowledge of the Japanese people. I have discovered firsthand that they have a very positive attitude towards life and a very strong work ethic. They are also well-organized, which makes Japanese life less stressful.

- What do you plan to do after your fellowship ends?

I will continue my research in the area of robotics and biomechanics in the Institute of Mechanics at the Bulgarian Academy of Sciences. I have accumulated substantial experience which will allow me to participate in other projects in the future. I have also had a lot of conversations on robotics and medical engineering with other scientists. So, I hope to continue not only my collaboration with my colleagues in this laboratory but also to strengthen the relationship enjoyed between my department at the Academy in Bulgaria and this laboratory in Japan. Furthermore, I want to establish new connections with other researchers in Japan.

- Please give some advice for young researchers who may be thinking about doing research in Japan?

I would definitely recommend that they come to Japan because the research staffs are very professional and the laboratories are well-equipped and offer an excellent research environment. Japan is also a beautiful and safe country. You will find the Japanese to be a very polite, honorable, hospitable, and reliable people.

From our interview with him, it was abundantly apparent that Dr. Kotev has both enjoyed and found very fruitful his stay in Japan. His research with Dr. Mouri and his lab mates has advanced steadfastly step by step. There is a very high demand within the medical community and among the general public for the kind of robotized systems they are developing to perform orthopedic surgery. The considerable time and effort he has devoted to advancing this research, the deep understanding he has cultivated of the Japanese culture and people, and the strong bonds he has tied with his Japanese colleagues are sure to pay great dividends after he returns to Bulgaria both in advancing milestone research there and in promoting vibrant collaboration with Japan.

Introducing Japan: Gifu City

Currently, I am living and working in Gifu city. It is a beautiful and quiet city located in the central part of Japan, only 20 minutes by train from Nagoya. Its location is very convenient for travelling both around Japan and internationally as one can easily get to the Chubu Centrair International Airport in Nagoya.

Gifu is surrounded by mountains. The most popular among them is Mount Kinka in the heart of the city. The Nagara River runs along its foot and the famous Gifu Castle sits on its top. The castle was the residence of many lords, among them Oda Nobunaga, who initiated the unification of Japan in the late 16th century after a long period of warring states. The castle was destroyed at one point, then reconstructed to its present shape in 1956. Making this place especially attractive is a ropeway that goes directly from Gifu Park, at the base of Mount Kinka, to the castle on the mountain top, which commands a lovely view of the city. People who like climbing can reach the top by ten different routes. For those who prefer walking, Gifu Park is a wonderful place for taking a stroll. There are stone paths going around a lake, and in the evenings the whole area is illuminated with hundreds of small lamps.

The city is also well-known for its cormorant fishing on the Nagara River. This is an old art of fishing dating back some 1300 years. The powerful leader Oda Nobunaga patronized this art, setting the stage for it becoming such a long-lasting tradition. What makes cormorant fishing so interesting is the way in which the fishermen on the boat skillfully manipulate several cormorants that swallow the fish (called ayu). This ritual of fishing can be observed from sightseeing boats that pick up the spectators from a quay. Even more spectacularly, the fishing takes place at night with fires (kagaribi) in iron baskets hanging from the fishing boats to light up the river's surface.

Another place one should visit in Gifu is the Gifu Great Buddha (Shoho-ji Temple) that accommodates a 13-meter high statue of Buddha. One can also take a walk through the roofed Yanagase shopping arcade in downtown Gifu city. It offers a full array of shops, restaurants and bars—something for every taste. For those who enjoy relaxing in a hot spa (onsen), there are several hotels near Mount Kinka with onsen baths (one being Nagaragawa Onsen). Sitting in the hot spring water, one can enjoy a nice view of the mountain.

Finally, Gifu is also famous for its paper lanterns, one of the city's traditional crafts. They are built around a thin wooden frame and can be plain or decorated with scenes. Most of these lanterns are still made by hand, which makes them a genuine article of art.

So, I would recommend Gifu to those who are looking for a relaxing holiday or who are interested in history and traditional crafts.

Sitting atop Mt. Kinka
With his wife Galina in Gifu Park