Photothermal-effect is the method to get driving force due to the thermal stress by temperature gradient that changes light to heat. Micro-cantilever is the simplest elements of micromachine that is driven by using modulated laser diode (output 10mw). Frequency response characteristics and deflection of a micro-cantilever are measured. Applying the principle of photothermal driving of the micro-cantilever, standing wave is excited on the micro-disk. Frequency response characteristics, modal analysis and amplitude of the micro-disk are measured. The micro-disk is made of copper which diameter is 10mm and thickness is 80 μm. Standing wave of mode shape No. 2 and mode shape No. 3 is excited on the micro-disk. Traveling wave is excited on the micro-disk by using plural lasers. Traveling wave is excited on a micro-disk by using two modulated laser diodes. Amplitude of traveling wave and phase difference are measured. The traveling wave of mode shape No. 3 is generated on the micro-disk and maximum amplitude is 0.26 μm.

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An injection molding has generally been used in the production of plastic lenses. However, it is difficult to make the die and optimize the molding conditions for large-sized lenses. In this study, the cutting of a large-sized lens using ultraprecision lathe was attemped.
Acrylic is easy to warp by cutting heat, which sometimes deteriorates the lens performance. So first, the fundamental cutting characteristics of acrylic were investigated to obtain a flat surface by face milling. Experimental results made it clear that the warp could be controlled and acrylic with the fine flatness was achieved by considering the cutting heat. Next, finishing condition for acrylic was examined with various kinds of cutting tools in the ultraprecision lathe. As a result, it was clear that the tool material affects optical characteristics such as the transmissivity and refractive index. But, by using a monocrystalline diamond tool with the suprior thermal characteristics, a large lens 430 mm in diameter could be cut, and the optical characteristics of acrylic material could be retained.

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This paper introduces Shuttle Unit, attachable to an ultra precision milling machine, for high speed machining of micro-grooves and micro-dimples. The shuttle, which is pneumatically supported, is driven by a kind of linear motor at 1.2 m/s, reciprocating three times per second. The reaction of the Shuttle is compensated for by its unique reaction-free structure. This unit can machine 3 grooves in a second. The surface roughness of grooves is 1.0nm Ra. Grooves are fabricated sharply without burrs even in the groove pitch of 0.3 μm. It can also machine 200,000 dimples in 4.5 minutes. The error of each dimple's position is less than 1 μm even though Shuttle's speed is 1.2 m/s. The unit has achieved high efficiency machining and ultra high precision machining at the same time, thus resulting in shortening the machining time of optical parts such as light guiding panel mold and diffraction grating.

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The cutting performance of cBN tools for high-speed end milling of hardened steel is investigated. The cutting characteristics are evaluated by tool temperature at the flank face, cutting force, chip geometry and surface roughness at the change of cutting speed ν and workpiece hardness. The temperature of cutting tool is measured using a two-color pyrometer with an optical fiber. The tool flank temperature θ_α increases with the increase of cutting speed and workpiece hardness, and reaches approximately 850°C at ν=600 m/min and HRC60. In particular, the workpiece hardness has great influence on the tool flank temperature. On the other hand, the principal cutting forces does not change so much with workpiece hardness. Based on the chip geometry measured, the most likely explanation for these phenomena is that chip formation process changes with workpiece hardness. As the workpiece hardness increases, the cutting actions become stable so that the surface roughness decreases. In the case of the low cBN content tool, tool flank temperature increases by 20∼50°C or more than high content one, because of the low thermal conductivity.

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The paper deals with the effects of an MQL (Minimum Quantity of Liburication) process on drilling of 0.5% carbon steel. In drilling, discharge of chips from a hole drilled, tool wear, accuracy and surface roughness of the hole are the biggest problems, especially in deep drilling. MQL process gives fairly good results about these problems if suitable cutting conditions are selected. However the mechanisms have not been clarified yet. In this study, drilling tests with different lubrications, i.e. dry, MQL and wet, were carried out on the steel using solid carbide twist drills having two through holes. Tool life, cutting forces, profile and surface roughness of inside wall of drilled hole, enlargement and cylindricity of drilled holes were examined. Results obtained were as follows. (a) The longest tool life and the best quality of the drilled hole were obtained in MQL process. (b) Diameters of drilled holes in MQL process were larger than those in other process, while cylindricity of the hole in MQL process is better than that in other process. (c) The maximum torque in MQL process is smaller than that in other process.

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The present paper deals with a fabrication method of micro Ni-W electroplated diamond tools with a diameter of 100μm and their machining characteristics in grooving into silicon, in order to estimate the machining performance of the tools and optimize the fabrication conditions. In fabricating 2-4μm diameter grit tools, more uniform distribution of grits was obtained through the solution stirring by jet, which resulted in a reduction in tool life scatter. The optimal electric current density was obtained regarding tool condition and tool life. Cutting speed and feed rate were optimized from the viewpoint of tool life.

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The purpose of this study is to enhance the calculation accuracy in the region of which the diameter of the orifice and the guidance clearance are comparatively small in the aerostatic guidance design. Specifically, the amount of air flux passing through said orifice is calculated in two separated parts, one part is the calculation done on the boundary layer flow whereas the other part on the potential flow. In this case, the calculation of the boundary layer flow is attempted using a theory in which the surface roughness is taken into account. That is, the calculation is done based on a virtual cylinder which has the same area as that of the rough inner surface of the orifice calculated based on the measured value of the surface roughness of an orifice cut surface. As a result, in the region abovementioned the calculation results of the flux, the recess pressure, the load capacitance and the static rigidity, are in a good agreement with the experimental results.

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Many researches of the gene using the transgenic mouse have been performed. 600,000 kinds of mice are produced for the elucidation of gene function. For this reason, the microchip for individual discernment for discriminating and managing huge kind of mice must be developed. In this research, the detailed structure and functions of the micro pressure sensor were investigated by the FEM analysis. About 96 kinds of sensors are made by the consideration of analytical results. Fundamental characters of micro pressure sensor to measure the ventricular rate using this device were clarified.

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We have developed a system for measuring the photoelastic constants of optical films using an optical heterodyne technique generally used to measure birefringence. The system included a compact tension tester and was automated by software. When measuring an optical film used for a liquid crystal display under low stress, which is difficult with conventional measurement techniques, we could determine whether the photoelastic constant was positive or negative and obtained a value of +0.14×10^-12/Pa.

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This paper addresses an air-type active anti-vibration apparatus. An important development issue is to reduce the natural frequency. However, it is known that the high frequency dynamics of its apparatus influence on the positioning and measurement accuracy of mounted precision instrument. In order to suppress the dynamics, i.e. the pipe resonance of anti-vibration apparatus, the influence of both the piping material and the pipe length on the high frequency response is experimentally investigated.
Firstly, the electrical methods to suppress the resonance are shown. In detail, both the notch filter technique and the differential pressure feedback are described. Secondly, the resonant characteristics due to the pipe length and the pipe material are experimentally shown in order to develope the mechanical suppression means. Through these experiments, noteworthy phenomenon, namely the disappearance of pipe resonance in case of special pipe length, is found out. Though the pipe resonance has been recognized as Helmholtz-type, it becomes clear that this understanding is slightly mistaken. Finally, a mathematical model for control is presented. Some experimental results can be explained using this model. However, the above-mentioned phenomenon cannot be successfully explained.

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In this paper, we propose a 3-D measurement method of objects' shapes in liquid using the light stripe projection method. When applying vision sensors to measuring objects in liquid, we meet the problem of an image distortion. It is caused by the light refraction on the boundary between the air and the liquid, and the distorted image brings errors in a triangulation for the range measurement. Our proposed method can measure the accurate 3-D coordinates of object surfaces in liquid taken for calculating the refraction effect. The effectiveness of the proposed method is shown through experiments.

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In recent years, the CMM (Coordinate Measuring Machine) quickly has been spreading in the manufacturing industry. With this phenomenon, the environmental condition and installation site of CMMs has been changed from the temperature control room to the workshop environment and the production line without air conditioning. However, even in severe environment the demand to high accuracy measurements by CMM has been enhancing still more. Therefore, the methods to evaluate and realize the high accuracy measurements by CMM in workshop environment have been investigated. In this paper, we clarify the difference of thermal drift and conventional temperature correction in thermal errors of length and position measurement, and propose the simple model of thermal drift and correction method. Additionally the thermal drift of CMM in workshop environment is tested and corrected experimentally. From these results, we confirmed the availability of the proposed methods.

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In this paper we report the development of a novel actuator for surgical assist manipulator to perform minimally invasive surgery with magnetic resonance imaging (MRI) guidance. The actuator, which is called the spherical ultrasonic motor (SUSM), is constructed of a spherical rotor and three ring-type stators, and has multi-degrees of freedom. In this study, the principle of the SUSM is described. A novel SUSM composed of non-magnetic materials has been constructed, the stator of which was designed using the finite element method. Evaluation of the driving characteristics revealed the SUSM to have good responsiveness and high positioning accuracy. In MRI environment, the noise effects of the SUSM on MRI images were examined. The results demonstrate the feasibility of the surgical assist manipulator using the SUSM.

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The need for the automated analysis of sporting activities has increased dramatically. In this study, we analyzed and quantitatively evaluated tennis swings using computer vision. Two cameras are used to detect the positions of balls and rackets in 3-D. By subtracting successive images from each other, the relative positions and 3-D trajectories of balls and racket centers are calculated. An ellipse fitting method is used to estimate the racket contours and the normal vectors of the racket face are determined. Racket face angles are calculated using the components of the normal racket vectors, with three different shots (flat shots, slice shots and drive shots) being quantitatively discriminated using these angles. Ball and racket speeds for five stroke types ranging from beginner to expert are calculated and compared to evaluate shot techniques.

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Large molds with very deep shape are well used in producing bumpers and inner panels of automobiles. In order to realize the precise and stable machining of such deep molds, 3-axis milling with inclined cutters are often applied. In this paper, we propose a new algorithm for determining the optimal cutting direction in such inclined machining. We introduce a concept of accessible cone as a measure for evaluating the stability and safety in the inclined machining, and we define the optimal cutting direction as the direction whose corresponding accessible cone has the maximum peak angle. The accessible cone for a specific cutting direction can be derived by rendering the silhouette picture of the offset shape of the mold. This computation can be accelerate by using the graphics processing unit (GPU) which is now equipped in most PCs. Proposed algorithm is implemented and an experimental process planning assistance program using this technology is demonstrated.

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