In recent years, automated vehicle researches move on to the next stage, that is, auto-driving experiments on public roads. To realize practical performance, some static information should be kept on memory such as road topology, building shape, white line and so on. Some measurement companies have already begun to provide highly-precise 3-D point cloud. This study focuses on how to realize accurate localization based on the use of LIDAR data with precise map. In different roads such as urban road and expressway, the observation information of surrounding roads is significantly different. For example, on the urban road, many buildings can be observed at the upper part of the vehicle. Such observation enables to realize accurate map matching. On the other hand, in the expressway, the upper part of the vehicle has no specific observations. Therefore, it is necessary to observe the lower part of such area for the map matching. To adapt to the situation changes, we propose a localization method which is based on multi-layered scan matching. The main idea is to effectively use the features observed in different heights. Localization experiments show that the proposed method is able to estimate accurate vehicle position in different driving areas.

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In recent years, due to advances in science technology, space satellites have made progress. So, the presence of space debris has become problem in the world because they may collide each other. In our study, we have developed Spherical Ultrasonic Motor (SUSM) for space use with 3 DOF to drive the satellite thruster and resolve it. We aim that the satellites enter the atmosphere when the satellites reached the end of life, and SUSM controls thrusters when they inject for the directional control. We have made experiments of measuring torque, durability and lifetime. It shows that the torque and lifetime meets target value. But durability does not meet target value. To resolve it, we have applied stator lining materials and shifted frequency with 0.4kHz from resonant frequency and we have shown that it meets durability-required specifications.

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Removal characteristics of zinc oxide film used as a transparent conductive oxide were experimentally investigated using a square fiber and nano-second pulsed laser. Effects of the intensity distribution of the laser beam on removal phenomena were discussed with a combination of an achromatic lens and a single lens. An achromatic lens achieved better groove shapes with a narrow damaged region, but the electrical insulation state was unstable, in which scribed groove could not achieve insulation state even at a higher overlap rate around 80%. High-speed observation revealed a possibility of zinc oxide film remaining on the glass substrate, since dominant removal of zinc oxide film progressed uniformly inside the spot area in thickness direction of film. On the other hand, a single lens resulted in a wide damaged region, but the electric insulation was obtained stably at more than a certain overlap rate. Because zinc oxide film was removed from center to outer side inside the laser spot with pushing material in width direction, and zinc oxide film was almost completely removed at the center area of laser spot. Therefore, the combination of a singlet lens and a slit mask was proposed to attempt different intensity distribution in parallel and perpendicular direction to scanning line. This optical setup could achieve both stable electric insulation state and better groove shapes with a narrow damaged region at more than overlap rate of 60%.

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A curved-hole machining method by EDM using an electrode consisting of a metal ball suspended with a lead copper foil from the spindle head of an electro-discharge machine has been proposed and the fundamental machining characteristics has been discussed. This paper discusses the effects of the diameter and mass of the metal ball on electrical discharge machining characteristics. The use of a 5.5-mm-diameter ball electrode may provide stable machining performance under a wide range of electric conditions. On the other hand, with decreasing ball diameter and mass, the stably machinable conditions are limited to lower discharge current and higher servo voltage. A smaller diameter hole can be machined by using a 3.0-mm-diameter ball under the optimum conditions. Additionally, a curved hole with small diameter is successfully machined by varying the tilt angles of the workpiece during the process.

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