[in Japanese]

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This paper describes the method with high accuracy and high efficiency. The correction recording is done through the following procedures: (1) Recording graduations normally on the slave scale referring to the master scale. (2) Measuring the scale error. (3) Erasing. (4) Rerecording to cancel the scale error referring to the error data. The next two basic methods are executed to control recording pulses in the step (4): (a) Correction recording referring to the interpolated pulses of the masterscale. (b) Correction recording by the time conversion method. The following became clear: (1) The transcription with an accuracy of about 1'' can be done by the method (a). (2) The transcription with an accuracy of about 0.2'' can be done by the method (b) within the correction values of 1''. (3) Applying the 2 step correction recording method, which is combined method (a) with (b), to the masterscale, the scale with an accuracy of about 0.5'' has been recorded.

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Usually, two optical fiber plugs are connected by facing each endface of the plug ferrules and inserting them into the alignment sleeve. The concentricity of the fiber core with the plug ferrule is, therefore, most important to decrease misalignment at the connection, hence the loss of signal transfer in fiber optic links. The present paper aims to develop a machining system capable of turning the plug's cylindrical surface so as to become concentric with the fiber core within the tolerance of ±0.5 μm. The principle of the developed machining system is as follows. The light incident at one end of the fiber is guided and emitted from the endface of the plug ferrule to be machined. This light is amplified and detected by the position sensitive device (PSD), then the center of the light spot is calculated. The plug ferrule to be machined is mounted on the XY table and positioned so that the fiber core is concentric with the center of rotating cutter according to the output signal of the PSD. The development of each element and the overall performance of the system are described.

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This paper describes a new view control mothod that utilizes the view through TV camera for tracking a moving object. Two fundamental techniques for view control are studied. One is a method for detecting the state variable that characterizes the moving object based on its approximation by a circumscribed rectangle. The other is a background elimination method that employs both background image estimation and noise elimination by superposition of images. The validity of these methods are confirmed by experiment. Further, it is shown that both methods realize view control for tracking a moving object with ease in an actual background.

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This paper discusses ultrasonic measurements of three dimensional (3 D) coordinate. Two methods are introduced in which two or three different ultrasonic waves are used. From a moving transmitter, waves are sent intermittently to eliminate influence of reflected waves and received by some fixed receivers. Phase differences are measured between the transmitted and received waves to calculate the distances between the transmitter and receivers. Then 3D coordinates are calculated by triangulation. The first method uses three kinds of waves and 3 D coordinates are determined only from the measured phase shifts. In the second one, the phase shifts of two waves and propagation time of one wave are used. Some experiments are made in a space of 300 mm×300 mm×1000 mm. By the first and second methods, errors of 1 D measurements are less than 0.1 mm and those of 3 D measurements are less than 1 mm.

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Flank wear characteristics of tungsten carbide tools in turning plain carbon steels without built-up edge have been investigated by measuring temperature, normal stress and wear rate on the flank wear land. It is found that the crater wear characteristic equation, derived from the adhesive type wear model after M. C. Shaw in the previous paper, is able to describe the flank wear as well. However, the characteristic equation of flank wear consists of two characteristic lines with different gradient which intersect at the critical temperature of around 1150 K. It seems that the line in the low temperature side is affected by abrasives in the steels. This abrasion effect could be taken into account by changing the constants involved in the wear characteristic equation. On the other hand, an abrasive type wear equation could be derived so as to have the same expression as our wear equation. Observation of the wear particles by Uehara, however, appears to exclude the possibility of this wear model.

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Chip forms are affected by three factors being flow angle, side- and up-curl of the chip. A model of two-dimensional cutting, in which boundary of the chip and workpiece is constructed by two circular arcs, is proposed. Furthermore a model of oblique cutting is developed for predicting the chip formation and cutting forces. In the model it is assumed that the deformation in the plane normal to the cutting edge takes place as the same in the model of two-dimensional cutting, and translational velocity is considered for explaining the direction of chip flow. The model permits the existence over a wide range of shear angles. For oblique cutting one situation having a radius of up-curl of the chip is determined as the situation to be realized by minimizing the rate of energy consumption.

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Temper color produced in grinding is generally used for the index of thermal damages suffered on the ground surface. Although, there are some problems about the oxidation process of ground surface and the microstructure of oxide layer which represent the temper color. In the present research, the difference of oxidation process between ground surface and buffed one is compared experimentally, and the microstructure of subsurface layer is investigated with some micro analysis methods such as SIMS, TED, etc. The results obtained are as follows: (1) Fresh surface produced by abrasive grains is activated and tend to be oxidized. (2) Burned surface is covered with thin Fe₃O₄ film with thickness of scores of nano-meters. (3) Under the film, there is a compound layer composed of iron and iron oxide. The thickness of the layer is up to hundreds of nano-meters. (4) The compound layer has many micro cracks and it appears to be a thin layer composed of micro vertical pillars.

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Based on the fact that the major sources of the machining error in end milling operation are the deflection of the machine-tool structure including tool holder, end mill, and their connecting parts, the relation between these deflections and the machining error is formulated. According to this formulation, the instantaneous cutting force can be calculated by using an oblique cutting model and then the machining error and its individual error components can be analyzed. The results obtained are as follows: Cutting force calculated by using an oblique cutting model is close to the measured value. Machining error and its components can be predicted qualitatively and quantitatively for various cutting conditions. Error component due to the end mill deflection decreases when the cutting point approaches to the holder-end side. Deformation of the jointed part at the end mill-holder connection can not be neglected, and varies depending on the tool holder used.

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This paper describes experimental results on how machining conditions, such as magnetic pole shape, magnetic flux density, work speed, vibrating frequency, vibrating amplitude, working clearance, mean diameter of magnetic abrasives, etc., influence the finishing characteristics of non-ferromagnetic substances. From the results, it has been determined that the finishing characteristics are equal qualitatively, but are different quantitatively compared to those of ferromagnetic substances, and the machining efficiency is considerably lower because of both the magnetic field distribution and its field strength in the working zone. Furthermore, it has been clarified that a magnetic abrasive finishing process has the finishing capability of a ceramic bar.

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Now the users of composite materials have faced a difficulty to machine them, because knowledges and experiences acquired for conventional materials can not be applied to such new materials, of which machinability is completely different from that of conventional materials. This seems to necessitate fundamental investigation into the cutting mechanism of FRP. In this study, firstly, the chip formation in orthogonal cutting of GFRP of simple continuous fibres has been observed for varied fibre angles. Secondly, the cutting force and the roughness of machined surface are measured in reference to the fibre angles, and the cutting temperature is experimentally obtained by a special device. The cutting force becomes minimum approximately at 30 degree fibre angle and it increases steeply with the increase of fibre angle. The roughness of machined surface exhibits a similar trend to that of cutting force. The cutting temperature in machining GFRP is comparatively higher than that in machining ordinary metals, and it increases more steeply with the increase of cutting speed compared with the case of metal cutting. In addition to it, a mathematical model to estimate the cutting force, which is a function of fibre angle, has been proposed.

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The purpose of the paper is to obtain the most efficient infeed curve of wheel spindle stock in plunge grinding. In accordance with this infeed curve, workpiece can be ground at the shortest cycle which is consistent with required quality and accuracy of product. For example, the cycle time can be reduced about thirty-five per cent compared with the grinding at a fixed speed. The quality and accuracy are evaluated by size, roundness, surface roughness and affected layer. The effect of grindability, which changes with stock removal, is also investigated on the infeed curve.

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Chippings on the corners of works in grinding of ceramics are investigated in terms of shape and size. The grindings are carried out by single point diamond tools to clarify the effect of wheel depths of cut, work velocities, shapes of diamond point, angles of work corner and work material on the chippings. The main results are as follows: (1) The shape is characterized by a bell-bottom shape spreading toward the corner on the top side and a sectorial shape extending downward on the end side. (2) Their size on the exit corner in up grinding is the biggest of four kinds of the corners. (3) Their size is affected more largely by wheel depths of cut than by work velocities. (4) Sharp point in a diamond abrasive, dull corner in workpiece and tough material such as PSZ are desirable to use for attaining small scale chippings.

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A design optimization method of machine tools, based on the clarified relationships between evaluative factors of machine-tool dynamics, is proposed. Clarification of competitive and cooperative relationships between characteristics results in division of design variables into three groups. The design variables of each group are determined in each of the multi-phase design optimization procedures. The design decision problem in each procedure is far simpler and easier than that in usual design optimization methods, in which all design variables are determined at the same time. Algorithmic procedures of the design optimization method are described, and effectiveness of the method is demonstrated on a structural model of a milling machine.

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Theories of the 4×4 determinant approach to interference problems are described, in detail, in succession to the former paper. First, various cases of the 4×4 determinant are discussed including the geometric implications. Secondly, normalization of the determinant is proposed. Lastly, an intersection formula in homogeneous coordinates is verified which makes it possible to do consistent homogeneous coordinate processing from the very beginning of geometric modeling to the very last of displaying objects. This article will provide theoretical foundations for the 4×4 determinant approach in computer graphics and geometric modeling.

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