Vertical-scanning shape-measurement interferometry using white light is widely used to measure 3D shape of objects having step-like shape. This interferometry however cannot be used under vibrating environment. Because, it is required to accurately repeat predefined-step movements over vertical measurement range. We developed new technology which can measure the changes of optical path difference (OPD) of an interference microscope with nanometer resolution. This uses a line camera and a FPGA device and can measure OPD changes with around 20-μs interval. We built this technology onto a vertical-scanning interferometer and estimated performance of the developed technology using some vibration conditions.

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This paper describes the measurement method of surface roughness by specular reflectance S_r using a single slit. The reflectance is calculated by the ratio of incidence to reflection light and linearly decreases with increasing the surface roughness parameter R_a. The reflected light need to be measured at a regular angle of the diffraction pattern because the illuminated light at the rough surface scatters around the angle. The measurements of S_r are carried out with some specimens of metal and nonmetal. The measured results of S_r were accord with approximate line of a linear equation of R_a at the incident angle larger than 75°. By analyzing an approximate line, the measurable domain of R_a can be selected by the complementary angle Θ_i of incident angle φ_i.

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When using semiconductor lasers to detect extremely small objects, smaller laser beam spots allow higher resolution. For example, the optical head for optical disk generates an extremely small spot of light to detect an extremely small pit that represents data on the optical disk, thus realizing high storage capacity. The spot size is determined by the wavelength of the laser and the numerical aperture (NA) of the objective lens. So it cannot be below the diffraction limit. There is, however, a method of increasing the resolution of an ideal optical system by varying the state of the laser light that enters the objective lens. This is a kind of super-resolution. That method, however, generates side-lobes, which are a characteristic of super-resolution. In this paper we propose the super-resolution spot shape suitable for data reading from an optical disk. We used a phase correction element to get the super-resolution spot. With practicality as a priority, we simplified the element structure to the fullest extent. We confirmed effective data reading from an optical disk using this phase correction element.

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In the semiconductor and LCD manufacturing industry, there is a strong demand for measuring film thickness and surface profiles of film-covered objects. In this paper, we propose a single-shot algorithm for simultaneous measurement of film thickness and surface profiles. Unlike existing multiple-shot methods, our method requires only one image for measurement and thus it is fast and highly robust against vibration.

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The speckle interferometer based on multi camera technology using two cameras is applied to a dynamic measurement in this paper. A phenomenon that the package of an electronic device is deformed while running is investigated by the novel technique. To perform high precise measurement by this method, the optimum conditions for measurements are also discussed concerning the size of speckle and the frequency of carrier signal. The deformation process of the object can be analyzed high-resolution. Under the optimum conditions, the deformation process of the package during the operation of an operational amplifier is measured. Then, the local maximum deformation can be estimated as 150nm from experimental results. From the results, it can be also confirmed that electronic devices are deformed by the stress of a heat by an operation every second during the operating time.

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A non-contact method for precisely detecting the tip position of micro-tools is proposed in this paper. The tip position of a micro-tool must be detected for milling work pieces precisely. Conventional detectors for the tip position of micro-tools can break the tip of the micro-tool by contact force or fail to detect all three axes. Therefore, the tip position of a micro-tool must be detected precisely without contact. An optical set-up to detect the position is composed of a microscope and optical devices. A CCD camera in the set-up produces magnified images of the tip of the micro-tool, and contrasts between the tip images are calculated. The shallower the depth of focus of an objective lens, the smaller the width of the contrast peak. The tip position of micro-tools is detected without contact by the repeatability of the contrast peak position of images. Experiments are conducted to confirm that a highly repetitive detection accuracy is obtained by this method. In the experiments, two parameters are used: the calculating range of the contrast and the direction of the detecting line of light intensity distribution obtained by the CCD camera. The two parameters are optimized from the experimental results. The parameter called the contrast calculating range has the highest precision repetitive detecting position, provided that it is longer than 3μm. Fringes with a high spatial frequency and a detecting position with a high repetitive precision are obtained when the direction of the detecting line is at a right angle to the direction of the cut made in the micro-tool. Considering the circumstances mentioned above, the degrees of precision in the repetitive detecting position were 2σ=±0.036μm (φ0.04mm Square endmill) and 2σ=±0.019μm (Nose R0.05mm Ball endmill). These experimental results show a higher level of precision than tool position detectors currently in use. The proposed method has sufficiently high performance to allow detection of the position of the micro-tool.

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A pin wheel type reducer having no eccentric input cam has been newly developed. This reducer consists of an input disc with a trochoidal shape groove, a train of movable pins which are arranged to the equivalent angular pitch, a fixed cam and a reduction cam. The difference between the number of teeth on the fixed cam and the number of teeth on the reduction cam is two or more. And this difference conforms to the number of the trochoidal shape lobes on the input cam. The fixed and reduction cam are meshed with the train of pins simultaneously. In cases in which the input cam rotates, the meshing points on two cams rotate along the trocoidal shape. At the full rotation of input cam, the reduction cam rotates oppositely through the reduced angle which is proportional to the difference in the number of teeth. It can get high torsional rigidity and keep the balanced and steady rotation. In this report, the motion principle is investigated, and the cam profiles are shown based on motion of the pins. And the design conditions of an undercutting avoidance are investigated using polar complex vector analysis.

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This paper deals with monitoring of spindle displacement of machine tool by utilizing position sensitive detector(:PSD). PSD and miniature LD module are arranged far from each other at opposite side of rotating spindle with slit in radial direction. PSD detects the position of part of laser light cut by the slit. The position change corresponds with the slit displacement. And elongation between the slit and the end surface of spindle is estimated as a homogeneous thermal expansion from temperature increase of the portion measured by non-contact surface thermometer. According to sum of the slit displacement and the expansion, tool position is controlled by piezoelectric actuator. It is clarified that the controlled tool position coincides well with the position of end surface of spindle under continuous and discontinuous operations.

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In milling with ball end mills of die and mold having various inclined or curved surfaces, tool paths are adopted along an axis of workpiece coordinate system or contour line on workpeice surface. In this paper, a cutting model proposed in previous paper is applied to the milling along the contour line of inclined surface, and cutting forces and chip formation under various inclined angles of the surface are predicted. In the milling of inclined surface in which the left side surface of feed direction of the tool rises, it is obtained analytically that the variation of cutting forces with rotational angle becomes large and rapidly changes. This phenomenon is caused by difference of geometric quantities such as tool-workpiece contact region and undeformed chip thickness along the cutting edge with feed direction of the tool on inclined surface. Predicted results are good agreement with experimental results. From 1st to 4th reports of this investigation, it is confirmed that the cutting forces in various milling process in which both cutting edges of sphere and cylindrical portions engage with the workpiece can be predicted well by using the cutting model proposed and energy method.

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When trying to trim the edges of a rectangular glass plate using thermal stress cleaving, the resulting crack path does not typically remain straight but will bend towards the nearby edge --- even though the path of the moving heat source lies parallel to the edge. This effect is brought about by the formation of a mode II stress singularity at the crack tip. Two dimensional finite element analysis of the transient thermal stress field shows that the mode II stress intensity factor varies according to the relative position of the heat source with respect to the cleaving line. Based on this analysis, three types of heat source profile are proposed to keep the cleaving path straight and parallel to the edge: a circular heat source, double circular heat sources, and a rectangular heat source.

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The study deals with the size reduction and performance improvement of automatic discharge gap controller (ADGC) for a microrobot which can fabricate a long curved hole by electrical discharge machining (EDM). The development of curved hole machining method is strongly required so that the pipelines with an arbitrary shape can be made in an arbitrary position. However, such pipelines cannot be fabricated since holes are generally formed by drilling. To solve the problem, the paper proposes a curved hole machining method by means of a microrobot with an EDM function. The microrobot has to have the function of performing the stable EDM in such a limited space as the bottom of a long curved hole, in other words, the function of always keeping the equipped electrode in an appropriate position automatically and autonomously so as to maintain stable EDM. ADGC is key component to realize the function. The prototype of ADGC was developed. However, the prototype was too large to install on a microrobot and did not achieve the full performance designed. Therefore, in the study, ADGC is improved to reduce its size and to achieve its full performance. From the experimental results, it is found that the improved ADGC realizes the full performance designed.

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This paper proposes a novel conceptual design method and support system named “Conceptual-CAD.” Traditional conceptual design consists of functional and shape design stages and these stages are executed in order. During the first or the functional design stage, a functional structure is designed by breaking down product's overall function into the collection of elemental functions. During the second or shape design stage, each part that achieves each elemental function is then designed and built up into the product. The proposed method also consists of functional and shape design stages, but two stages are not executed sequentially but executed simultaneously and cooperatively. Using the proposed method, both functional and shape structures are simultaneously designed from top down by considering the relationships between function and shape at each level. Such simultaneous and cooperative design enables simultaneous pursuit of high-functionality, high-performance, space-saving and weight-saving. In order to enable such design, this paper proposes a novel conceptual design method that consists of functional and shape design systems plus a shape realization system that supports the process of designing shapes from functions and a supervisor that checks discrepancy between functional and shape structures.

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