We have developed a master-slave type remote ultrasound diagnostic system in the "aged society". In this paper, the motion of the doctor while diagnosing is analyzed and according to the analysis, the specification of the system is decided. In the slave manipulator, it has 7 degree of freedom. 3 degree of freedom for position, 3 degree of freedom for orientation, and a redundant degree of freedom located in the tip of slave manipulator. Specifically, in the slave manipulator, high-rigidity was accomplished by adopting radius-guide ways to realize precise position and orientation of the probe and acquire the proper ultrasonography easily. And a redundant axis in the tip of the slave manipulator is implemented to trace the affected part keeping the contact force. In the master manipulator, a paralell link mechanism was implemented to lessen the volume of calculation by keeping the 3-axises force sensor horizontal. Then, we evaluated the safety of this system. In this paper, the results of the remote ultrasound diagnostic experiment between a multimedia cockpit with a medical doctor in Okayama prefecture and a consulting room with a patient in Tokyo prefecture are reported. Experimental results demonstrate that a medical doctor can perform remote ultrasound diagnosis properly.

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For the reasons of harsh environment in polishing procedures, an optical, non-contact measurement of surface roughness is better suited to in-process measurement than contact sensors such as a stylus meter. The authors have proposed a new optical method for measuring surface roughness by use of a halogen light source and a CCD camera. Based on the Torrance-Sparrow model, the proposed procedure theoretically converts the data of the reflected light into surface roughness represented in Rq (roughness in root mean square).
In this paper, we attempt to apply the proposed method to estimate a ground direction. From the results of the computer simulation and the experiments, the ground direction can be estimated within the error of 10 degrees. Further, the root-mean-square roughness can be evaluated within the error of 5% to the true value.

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The dynamic measurement of nanometer-order displacements was realized by using our heterodyne laser interferometry method. The measuring system of the existing method contains two analog devices, namely, a frequency divider and a phase meter, and various electrical and electronic noises are apt to be picked up by them. In addition the frequency divider has a minimum limit of 1/32 and troublesome manual operation is needed in the range exchange. To avoid the above inconveniences, we replaced the analog devices with a digital method using a special software package. The improvement was successful and the measurable frequency range was expanded to 300 Hz and above.

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Now, a wheelchair is being used widely. However many users have troubled for lumbago. In this research, lumbago prevention was approached by biomechanics and control engineering. As premise, lumbago was defined as rotation of a pelvis and change of a lumbar vertebra curve being the causes. Therefore, it approximates posture to the ideal vertebral column curvature, in order to prevent lumbago. Then, fast, the inclined angle of a pelvis and the curve radius of a lumbar vertebra in various seating positions were considered. Based on it, in order to reproduce posture change on a computer and evaluate lumbago, human equivalent model was created in analyzing anatomy in detail. Here, modeling was carried out by three sides, frame, mass and muscular. Posture change was simulated using the model which simplified the previous one on the software DADS. The simulation result of the evaluation model was able to express mathematically change of a lumbar vertebra curve as evaluation of an ache. As a result, it was verified that the built model is appropriate to evaluate lumbago. Furthermore this paper proposed the wheelchair with posture control for lumbago prevention adopting a swing seat, a lumbar support, and a pelvis support.

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One laser beam, which has Gaussian power distribution, is usually used for laser lithography. The solidification area is also a hyperbolic shape in this system. Thus, the surface of built parts is not smooth and a post-process to reduce surface roughness, using sandpaper and other methods, is required. In this research, we propose a laser lithography method using two laser beams. The second laser beam is used for complimenting the subtracted area from the CAD model and the solidification area of the first laser beam. From the experiment, we verified surface roughness for building truncated pyramid shapes was reduced using our system.

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A new method is proposed for calculating the profile of the cutting edge of the screw rotor hob. It is first gourd with a pencil type grinding wheel and then msharpened. When the profile of a pencil wheel is given as a dispersive points, theoretical equations are derived from them which represent the profile of the cutting edge after the resharpening. The profile error of the cutting edge of the hob was 16μm by the numerical analysis when the resharpening angle of the hob was 5 degrees. The calculation is made for the profile of the screw rotor which is cut by using the resharpened hob. Finally, it is clarified that the relationship between the resharpening angle of the hob and the profile error of the screw rotor.

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An anodic bonding process has been developed to silicon to ceramics with thin glass film. The optimized O ₂ gas mixture results in thin glass film on ceramics. The effects of the processing parameters of anodic bonding to pull strength of the bond of silicon to ceramics were explored in order to optimize this process. The bonding mechanism of silicon to ceramics sputtered glass film is disucussed. It can be obtained the advantageous structure of mechanical strength because of ceramics. This process was used to fabricate capacitive pressure sensor with silicon diaphragm of dimension in 20 μm thick.

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The alloying was carried out with the pre-placed and fixed alloying element powders or with highly alloyed sheet weighted down on the substrate. The substrate was a plate of Magnesium alloy AZ31C. An electron beam with a rectangle equivalent cross section irradiated and melted both alloying element and substrate while they moved constantly in a vacuum chamber. The alloying elements tried were Tin, Zinc, Aluminum, Gold, Silicon and 4 other metals. Manganese and Silicon were unable to alloy. To explain this phenomena a model was constructed that a molten alloying element column lying at the front edge of molten Magnesium pool was hindered to enter the pool by the vapor pressure of Magnesium. The result of model calculation agreed well with the experimental results. Micro Vickers hardness of alloyed layers was higher than the substrate hardness.

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In recent years, the ultraprecision micro machining technology is greatly expected in a variety of fields such as optical instruments, electronic devices, medical equipments, etc. At the time, it is essential to meet the requirement of producing various shapes, one of which is a structure with a high aspect ratio. Such a structure is applicable, for example, to a shaft of micro robot, a long part of micro actuator and micro machine, a micro needle for syringe, etc. However, it is extremely difficult to fabricate the structure with a high aspect ratio since it is easily crooked and broken during cutting. Thus, it is at first intedned to produce prismatic micro tower with a high aspect ratio, which has never been fabricated until now, by applying the ultraprecision milling technology with a single crystal diamond cutting tool. This method enables to accurately create a variety of micro structures with a high aspect ratio. In addition, the study also proposes a new machining method to create micro pin array, avoiding the contact of cutting edge with already machined parts again. Micro pin array may be applied to painless micro needles for syringe. As a result, it is found that the proposed method has the potential of producing a variety of micro structures with a high aspect ratio.

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A new method of a curved hole processing for cooling jackets of a metal mold is proposed. This processing technique is characterized by its simple mechanism without an actuator, where a tool is driven by the forward feed motion only. In the first step of the machining process, a tool slightly processes a hole into the direction where it is ordered to turn. In the subsequent step, the tool follows the hole machined by itself in the first process, and the repetition of these steps can produce a curved hole. The experiments carried out using electrochemical machining showed that the proposed method can produce smooth curved holes automatically. It was demonstrated that complicated curved holes with various curvatures were also produced successfully. These experimental results exhibited that the proposed method has a high potential as a processing method for curved holes in a metal mold.

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A recent technological trend in semiconductor industries is the use of large (i.e.8"or 300mm diameter) silicon wafers to improve the productivity and reduce the cost of silicon devices. The ID-blade traditionally being used for slicing silicon ingots, deteriorates the through-put when used for slicing large ingots. Wire sawing technology, therefore, has attracted attention and is now replacing the ID-blade slicing technology. Wire sawing with loose abrasives is widely employed today, but the process has problems relating to dirty working environment and low efficiency. Fixed-abrasive wire sawing using resinoid diamond wire tools has been developed for overcoming these problems, but the tools still have the problem of high production cost because thermosetting resin, which requires long time to be cured, is used as the bonding material. As the result, the diamond wire tool cannot be put to practical use. In this study, ultraviolet curing resin, which can be cured in short time, is used as the bonding material of a resinoid diamond wire tool to solve the problem. A series of experiments revealed that a newly developed wire tool can be manufactured at low cost and has a good mechanical property and a good machining performance.

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An electrochemical machining system using ultrapure water has been developed, designed for planarization machining and free-curvature-shape machining. The machining system is composed of three units: an electrochemical machining apparatus, an ultrapure water refining and circulation unit, and a high-pressure ultrapure water supply unit. The machining apparatus is equipped with an XYθ table and a Zφ machining electrode. A cylindrical or a spherical electrode is used for the machining electrode. The machining chamber is continually filled with refined ultrapure water by the refining and circulation unit. During machining experiments, process by-products, bubbles, and the like around the machining point can be efficiently removed by the high-pressure ultrapure water supply unit. Using this machining system, planarization experiments have been performed on copper plates, which are known to be easily etched, via application of a positive voltage. The effects of various machining parameters (current density, rotating speed of the electrode, etc.) on the roughness of the etched surface are investigated. It was found that the use of a high-pressure ultrapure water supply nozzle is effective in the planarization process. Furthermore, it was also found that there is an ideal set of conditions with respect to the combination of current density and rotating speed of the electrode. Copper plate surface roughness (Ra) was successfully reduced from 164 nm to 10 nm by planarization machining, with the optimal set of parameters.

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