In this paper, mixed-model assembly line balancing problem is treated. First, SI (Smoothing Index) for single-model problem is extended to MSI (Mixed-model Smoothing Index). Then, lower bound for branch and bound method is proposed and GA and SA are applied to this problem. Last, three solutions are compared by numerical experiments. In this result, branch and bound method is effective when restriction conditions are loose and SA is effective when restriction conditions are tight.

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This paper describes the measurement of temperature distribution and radiant flux distribution in the EDM arc plasma using the spectroscopic analysis. These distributions were obtained by the use of a lens which magnifies the image of the plasma and a mask which can limit the plasma region to be observed. The temperature distribution was computed from the radiant flux by the line pair method. This paper investigates first the influence of working conditions on the temperature distribution. Secondly, observing the radiant flux distribution in the plasma, the rate of evaporation of the electrode materials is estimated in order to understand the material removal mechanism. Thirdly, decrease in the plasma temperature during the discharge interval is measured in order to estimate the time required for the plasma to be deionized.

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Diamond fracture characteristics van, with the crystallographic orientation of the facets. The direction of grain facet on the surface of the diamond wheel is an important factor affecting the wheel performance. In this paper, the grain wear as influenced by the differences in the direction on the facets was investigated. Five types of model wheels were made of which fours consisted of grains with specific orientations of the facets and one random orientation representing a typical grinding wheel. Using these model wheels, grinding tests were carried out. on zirconia work material. The results obtained are summarized as follows: (1)Height loss of grain tip is caused by fracture in all wheels. (2) The edge shape is kept sharp by fracture enhancing grinding ability. (3) When {100} of diamond grain was oriented towards the grain tip and cut with <100>, height loss of the wheel is formed to be the lowest of all wheels. Consequently, this combination is formed to be optimal concerning the wheel wear.

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Solids and gases have widely studied in laser processing but there have not been so many reports about liquids applied to laser processing. Characteristics of liquids are as follows: liquid has high thermal conductivity, can suspend small particles and colloid, and dissolves gases. These characteristics suggest the possibility of using liquid as a substrate for film synthesis, surface-treating particles suspended in liquid and synthesizing small particles by excited gas dissolved in liquid by laser irradiation, respectively. This study focused on gases dissolved in liquid, so water was chosen as a liquid because of its large solubility, stability and high thermal conductivity. An ArF excimer laser was used because its wavelength is close to absorption edge of water. Firstly, the influence of the dissolved gas was studied and it is found that there is possibility of synthesizing substance in/on the water dissolving methane by laser irradiation. Secondly, synthesizing substance was tried. As a result, carbon films were obtained on the water by laser irradiation to the water from above. According to elementary analysis, solubility, Fourier transform infrared spectrometer, Raman spectrum and scanning electronic microscope, the films contain hydrogen and consist of small particles 30nm in diameter.

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In this study, in order to clarify the cause of the difference of adhering phenomenon between various titanium alloys and cemented carbide (K 10) in cutting process, diffusion bonding joint of these alloys was produced, and the relationship between high-temperature bending strength of the joint and form of reaction phases in bonded interface was examined. Though the diffusion bonding was done in temperature range from 1073K to 1473K and for the holding time of 0s on either titanium alloy, titanium carbide was formed as reaction phase. At Ti, Ti-6Al-4V and βC-Ti, forms of titanium carbide were massive, hump and layered types, respectively. As a result of 4 point bending test of bonded joint of each alloy at the testing temperature of 1373K, βC-Ti was high in comparing the bending strength with Ti and Ti-6Al-4V. As a result of observing the rupture position of test piece for bend test, in Ti, Ti-6Al-4V and βC-Ti, the rupture occurred in Ti inside, interface between reaction phase and Ti and cemented carbide inside, respectively. From the result of the diffusion bonding, the reason why βC-Ti is easy to adhere by the cutting process is because in βC-Ti, it forms the layered titanium carbide phase between the cemented carbide, and because it becomes a firm bonded joint.

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A lot of studies on the tool-path generation for five-axis controlled machining centers have been reported. However, the finished surface roughness has not been considered. For reducing the hand-finishing process of molds, it is great important to control the texture of finished surface. Especially, the surface texture finished by means of five-axis controlled machining centers is a significant factor to reduce the production time. In this research work, the generation mechanism of the surface texture is analyzed theoretically and experimentally. In the experiment, the eccentricity of the tool axis and the angular position of the cutting edges of the ball end mill are controlled according to the proposed algorithm in which the traverse time along the tool path is calculated precisely. From the experimental and theoretical results, it is found that the surface texture can be controlled by the proposed method.

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A radiation of the electron called exoelectron from the machined surface is observed with less energy than usual work function, and it is known that this phenomenon is sensible to changes of crystal structure and surface structure. This paper describes the result of examining the possibility of photo stimulated exoelectron emission as a method of the process monitoring and surface evaluation. As a result of cutting experiment in vacuum atmosphere, it is confirmed that electron emission is observed during the distruction of materials and that there is a relationship between cutting conditions and emission behavior on the machined surface. These results show the possibility of exoelectron emission for new method of process monitoring and surface evaluation.

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This paper presents a simulation method for 3-dimensional cutting processes. It is based on dynamic-explicit elastic-plastic FEM and forward Euler algorithm for heat transfer analysis. Because simultaneous equations of stiffness is not necessary for the methods, they are suitable for a FE model including a lot of nodes. We have proposed an efficient technique to include the effect of heat transfer to the tool. The method has been applied to the turning simulation of carbon steel (S15C). In the chip formation process, the side-curl has been observed mainly. This tendency agrees with one in the experiment. The cutting force has been also compared between the simulation result and experimental one in the steady state, and they roughly agree. The distributions of temperature on the tool rake face show the complicated process of heat transfer in the transitional state.

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This paper deals with the dynamic motion errors with XY synchronous motions in NC machine tools in terms of gain tuning. By analytical calculations and computer simulations, it is shown that the differences of the velocity loop bandwidth as well as natural frequencies of feed drives cause the transient errors on linearly interpolated motions inclined from X axis by 45 degree. Compensation methods based on dynamical matching of each axis and the acceleration feedforward technique are proposed to avoid such kind of transient errors. Motion error traces are measured on several combinations of servo gains and found to be very close to the estimated ones, which suggests the effectiveness of the proposed gain tuning methods of velocity loop gains as well as acceleration feedforward gains.

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Presently miniaturization and higher precision of products is remarkable. Therefore in order to maintain the quality of products, high accuracy is required of the machining process. Then tool form is one of important items to affect the machining accuracy and the machining efficiency of a product. Therefore it needs to be correctly grasped. Under the present circumstances, measurement of simple parameters, such as length and angles, is of main concern. So if it becomes possible to measure a curved surface form of a tool, a further improvement is expectable in machining accuracy, tool life, etc. In this paper, a new 3-dimensional profile measuring method is proposed. This method applies moire topograhy, produces slits using a line laser, generates a contour line moire pattern by image processing, and analyzes it. By this method, the measurement resolution can be set up arbitrarily and composition of equipment can be made simpler than in case where a slit is actually used. Moreover it is applicable also to shape measurement of plastic molding products, etc. Here, equipment is produced and the measurement performance of equipment is examined.

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A surface profile measurement method with high spatial resolution is proposed to measure errors in the shape of mirror surfaces. A grating with a sinusoidal transmittance is illuminated by expanding light and the image of the grating is projected on a screen. The grating is shifted perpendicularly to the striped lines of the grating in the grating plane and the intensity distribution of the images is recorded by a CCD camera. A fringe scanning method is used to measure the phase of the projected images of the grating. The grating is rotated 90° in the grating plane and similar images are recorded. Intersections of the projected images of two gratings are obtained at an equal phase position of the grating. A simulation of the designed mirror surface is calculated at a given phase. Intersections calculated by simulation and the intersections obtained by measurement are compared. Displacement of intersections caused by changes in reflected angles and the quantities are obtained as vector values which indicate the changes in the direction of the gradient of the surfaces at the intersections and are proportional to the magnitude of the gradient. By changes in the phase of the grating images, the same procedure is produced and a vector map of the displacement is obtained on the images. Changes in angles of reflection are analyzed over the whole surface of the mirror by the vector map. The errors in the shape of the mirror surface are analyzed by integration of the values of the changes in the angles. A head-up-display mirror with an aspherical shape was successfully measured by this method.

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A positioning control of the industrial robot arms requires a performance of a high speed and a high accuracy. However, torque saturation existing in the industrial robot arms often causes deterioration of the positioning control performance. A method of trajectory generation and modifying the taught data in the joint coordinates was developed for the high speed positioning control of articulated robot arms by taking into account of the torque constraint. The effectiveness of the proposed method was assured by simulation studies and experimental results of an actual articulated robot arm. This method can be applicable not only to two axes robot arms, but also to the general articulated robot arms. As the proposed method does not require any change of the hardware of the robot arms, implementation of the proposed positioning control for the existing industrial articulated robot arms is easy and effective.

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In recent vibration and acceleration pickup applications, for example in modal analysis, active control of vibration isolation, and inertial navigation, the phase shift evaluation of pickup has become important. However, the frequency-phase characteristics of the pickup has not been reported quantitatively from the production makers in the past. In this report, the phase shift evaluation results of three types (piezoelectric-type, servo-type and capacitance-type) of commercially available vibration and acceleration pickups are presented. The evaluations were performed using the sine-approximation method, which will be adopted in the updated ISO standards. The phase shift and the uncertainty of each pickup have been elucidated. Expanded uncertainties of less than ±6×10^-3 rad in phase shift evaluation at 5 kHz have been obtained. Three piezoelectric type pickups manufactured by different makers are also evaluated and compared. We observed a phase shift difference of up to 4×10^-2 rad in each sensor.

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In this paper, the relationships between the accuracy of measurement of an inner diameter and numerical aperture of a lens, the width of a parallel specimen gap, the z-direction displacement of a specimen and the degree of defocus of a detection lens are discussed theoretically using the noncontact equipment used to measure the diameter of small holes. The method for recognizing the position of the hole's wall involves the detection of an image of a small spot which is projected into a small hole and reflected on the wall. The results of theoretical analysis are as follows. The calculated position of the wall shifts toward the minus direction so the calculated inner diameter is small compared with the true value. The amount of shift in the middle of the specimen is smaller than that in the inlet or outlet of the specimen. The amount of shift depends on the degree of defocus of the detection lens. Therefore, the amount of shift can be adjusted by defocusing the detection lens.

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This paper describes a development of a method for motion recognition using frequency distribution considering motion transition in order to build an exoskeleton robot system for assistance in rehabilitation. Firstly, a method of recognition based on calculation of differences in frequency distribution between template data and current one has been proposed. Additionally, two sets of parameters were assembled to deal with keeping stiffness in sustained action and compliance in motion transition. Furthermore, method for detection of motion transition has been proposed and implemented into the system. As the result, the recognition ratio has been successfully increased to eighty percent by using the above-mentioned method.

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We have already proposed a position-based impedance control for industrial robots with an open architecture controller. In this paper, it is described on how to easily apply the impedance controlled robot to a profiling task along the object with curved surface and to improve the performance using a position compensator based on the cutter location (CL) data. The CL data generated by CAD/ CAM system have information of points along the curved surface and their normal vectors. If the object is manufactured with multi-axis numerical control (NC) machine tool, the CL data can be used as the prior information of object shape. The compensator using the CL data generates not only desired trajectory in the direction of position control but also feedforward information in the direction of force control. This technique allows us to obtain the desired trajectory without complicated teaching, and to improve the performance for profiling control. Some profiling control experiments using an industrial robot JS-10 are shown to demonstrate the effectiveness of the proposed method.

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If the state of a neural network can be ascertained at a certain time, then the state of the human behavior can be evaluated by comparing this with an average state. In the present research, based on the measurement of swaying condition in the standing position, we concentrate on a quantitative evaluation of a human stance posture control system and consider the attractor of a center of gravity, and thereby propose a new method for extracting its system characteristics. The posture control system is identified by using a neural network with an error back propagation method. Outputs from the network can estimate the difference of subjects and also the characteristic posture behaviors at different time. The proposed approach well indicates the human stance condition.

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A series of papers presents a new calibration method particularly for up to a middle size CMM. The method is able to provide the 21 parametric errors only by performing the coordinate comparison. An automated calibration system for the production stage of CMMs is realized. The first report describes basic structure of the linear parameter model which establishes relation between spatial displacement deviation observed by the coordinate comparison and the linearly combined parametric error components of the CMM. A simulation on a simple guide way example with six independent freedoms is performed to verify functionality of the model. The result shows that 96 parameters expressing six parametric errors are possible to be handled simultaneously. It is confirmed that the parametric errors are estimated with sufficient resolution to apply the model to the calibration of CMMs.

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