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An exterior light lens with a unique and finely textured shape was devised, which provides homogenous luminance, and luminance control technology of exterior light by arranging finely textured shape was developed. Because a die mold with a fine, three-dimensional lens shape is required when mass-producing the lens, we also developed a CAM (Computer Aided Manufacturing) that enables finely textured machining on a free-form surface and automatically produces a smooth machining path on a curved surface. This new technology allowed us to successfully develop a lens that simultaneously achieves transparency and homogenous luminance, properties not achievable through conventional technology.

Interior vehicle sound is an important factor for customer satisfaction. To achieve an optimized product sound at an early stage of development, subjective evaluation methods as well as analysis and prediction tools must be combined to provide reliable information relevant to product quality and comfort judgments. Binaural Transfer Path Synthesis (BTPS) is a well-known method to calculate interior noise and vibrations based on multi-channel input measurements. Recent enhancements of the BTPS method enable taking into account also simulated excitations, for example engine mount vibrations calculated using MBS and/or FEM simulations, allowing the prediction of interior noise even if the engine is not available in hardware. Interactive evaluation of the generated sounds in a vibro-acoustic driving simulator helps to increase understanding of customer responses and perception of target sounds.

A fundamental study was performed to develop a high efficiency solar heat receiver for a solar energy experiment mission on the Japan experiment module - exposed facility of the international space station. It is composed of a solar heat absorber, thermal energy storage and heat pipes. This system is aimed to transport solar thermal energy to a bottoming system with an efficiency of 80 %. Thermal analysis of each component was performed to assess its design approach. One ground testing model of the solar receiver was designed and fabricated in 1998, and then would be experimentally evaluated in 1999 at a test vacuum chamber of National Aerospace Laboratory.

The Alkali Metel Thermo - Electric Conversion (AMTEC) technology is one of the candidates to realize the high performance power generation plant using the various kind of thermal energy. For the terrestrial application of the AMTEC, various types of power generation systems are considered to be adaptable. In this paper, we present the conceptual design of the AMTEC module that is adaptable for the above terrestrial power plant, and the results of basic evaluation of the thermal performance of the AMTEC. On the basis of the above results, we evaluate the performance of three types of power generation plants. They are the simple AMTEC plant, the combined plant with the steam turbine and the combined plant with the Solid Oxide Fuel Cells (SOFC). It is shown that the thermal efficiency of the combined plant with the SOFC is expected to be over 60%, even if the thermal efficiency of the simple AMTEC system is about 37%.

The sodium β″-Al2O3 is one of the prime candidate as the solid state electrolyte in using the Alkali Metal Thermo-Electric Converter (AMTEC). This paper reports the properties of β″-Al2O3/ZrO2 composite electrolyte in order to improve the durability of the cell and its performance for the power generation as the AMTEC. It is shown that the addition of ZrO2 to the β″-Al2O3 is able to control the microstructure, and the fabrication procedure of the electrolyte with the ZrO2 addition is selected. This paper also reports the new concepts of the AMTEC cells that are connected in series in order to raise generation voltage and shows that the adaptability of the AMTEC for terrestrial power generation is improved by these concept.

A resonance type gear fatigue tester has been developed for fast and efficient evaluation of tooth-root fatigue strength. This tester is a sort of pulsating-type, and operates under quasi-resonance condition. One test gear is held stationary, and the mating gear fastened to a vibratory shaft oscillates against the stationary gear. The torsional vibration of the shaft is excited by a rotating eccentric. The torque amplitude is controlled automatically by varying the rotational speed of the eccentric and is maintained during a test. Fatigue tests and measurements of tooth-root strain were conducted on three kinds of helical gears, whose results were compared with those of a running-type fatigue tester. The results indicated that the tooth-root fatigue strengths with the resonance-type tester agreed with the running-type tester by taking the compressive strain which occurred at the tooth-root on the tension side in meshing, the dynamic load and the supporting rigidity in to account.