• Tactile sense and the sense of touch are multiple combinations of fundamental sensations, such as smooth and rough, soft and hard, dry and wet, and hot and cold sensations. These sensations are described with the information on force, distortion, temperature, stickiness and oscillation.
• A tactile sensor corresponding to several types of human skin sensory receptors and an active tactile sensor system that is an integrated sensor structure imitating human haptic motions have been developed. These sensor systems allowed measurement of "Kansei" words that are extremely vague tactile feelings, and roughness, softness and temperature sensations. However, tactile sense or the sense of touch also includes other sensations and combinations of them. Therefore, to develop a sensor, it is important to define how the sensations and physical information relating to the sensations are obtained and what relationships exist between them.
• In this research, the relationships between sensations, including fundamental sensations that have already been obtained and other sensations, and the relevant physical information are being investigated. Additionally, on the basis of the knowledge through the investigation, an advanced sensor system that allows obtaining haptic information is being developed.

The research is beneficial not only to life science but also to manufacturing fields.

• The main research subject of our group is developing material purification methods, crystal growth methods and detector fabrication technologies for compound semiconductor radiation detectors. Our group intensely studies a compound semiconductor, thallium bromide (TlBr), for fabrication of gamma-ray detectors for the advanced radiation applications. The attractive physical properties of TlBr lie in its high atomic number (Tl: 81, Br: 35), high density (7.56 g/cm3) and wide bandgap (2.68 eV). Due to the high atomic number and high density, TlBr exhibits high photon stopping power. The wide bandgap of TlBr permits the device low-noise operation at and above room temperatures.

Our group focuses on development of compound semiconductor radiation detectors for advanced radiation applications including ultra-high resolution PET systems, ultra-high resolution SPECT systems, photon counting CT systems and Compton cameras. We hope to conduct collaborative research with a willing company for a practical application of this technology in industry.

We aim to give high thermal conductivity to glass, which is known as a material that does not conduct heat well, and to apply it to new fields.

If mixed with a high thermal conductive material, glass can be a good conductor of heat. However, all the advantages of glass, such as transparency and freedom of molding, are lost. In this research, we succeeded in developing a transparent glass with high thermal conductivity that retains its glassiness by adopting the strategies of high thermal conductivity MgO deposition and refractive index matching.

• Transparent
• Free molding
• Thermal conductivity ~ 3 W/(m K) [300% of that of window glass]

Heat dissipation management using glass [heat dissipating glass substrates, lenses, fibers, etc.]

• Fukuyama laboratory studies novel material processing based on chemical thermodynamics with high-temperature thermophysical property measurements. As examples, we are developing new crystal growth processes to bring a breakthrough in nitride-semiconductor devices, which are promising materials for next-generation optical devices applied in environmental, medical, bio and information technologies fields. Database of thermophysical properties of materials is needed for modeling heat and mass transports in materials processes.

A new thermophysical property measurement system is currently under development, which enables accurate measurements of heat capacity, thermal conductivity, emissivity, density and surface tension of high-temperature melts, utilizing electromagnetic levitation in a dc magnetic field.

• For further social development, it is required the miniaturization, weight saving, high performance of various devices. We study on fiber, particle reinforced polymer, metal, ceramic matrices composite materials using our knowledge about materials mechanics and numerical simulation such as finite element method. We recently address to develop multi-functionalized composite materials, which have high strength, super lightweight, energy harvesting function, damage monitoring function, biodegradable at the same time.

• We developed both pH and Cl- imaging plates, which can visualize the pH and Cl- concentration on metal surfaces in acidic environments. The pH range is from 3.0 to 0.5, and Cl- concentration up to 4 M can be measured. Fluorescent dyes are successively used for pH and Cl- imaging in the field of biology, but their sensitivity tends to be insufficient in acidic and/or highly concentrated chloride solutions. A glass plate with a sol-gel sensing layer, which contains a pH indicator or a Cl- sensitive florescent dye was fabricated and validated using the solutions with various pH values and Cl- concentrations. Changes in the pH and Cl- distribution on stainless surface in an acidic environment were measured quantitatively.

The newly developed imaging plates can be used to investigate the mechanism of various chemical reactions, such as corrosion, which occurs in an acidic environment. Micro-flow imaging using our sensing technique will be a promising approach to understand the catalytic chemistry of metal surfaces.
強調

• Ti anodizing technique has been offered for coloring the surface of Ti, and its mechanism is understood by light interference varied with the oxide thickness. A characteristic of this study is to control the crystallinity of the oxide, and its originality is to provide photo-induced characteristics to Ti and its alloys by controlling the electrochemical conditions differed from that of coloration technology. This study is aimed for controlling the surface of Ti by using a simple and easy, inexpensive technique and to fabricate high functional titanium materials.

Related to practical applications, it is considered as a use for environmental purification such as deodorization and water purification, biomaterial and antibacterial and structural titanium.