Based on the fact that conventional cutting can not avoid the circularity error which is caused by cutting a deformed workpiece held by three-jaw power chuck, this paper describes three methods to compensate the circularity error using an NC lathe with the tool post driven by PZT to trace the surface of the deformed workpiece so that the resultant cut geometry becomes an ideal one after unclamping. The developed methods can realize a constant depth of cut for the deformed workpiece, during cutting by using the prediction by FEM and/or the measured data of circularity. The predicted data are accurate enough to use as the control input to drive the tool post and the results obtained by using developed apparatus showed the improvement of roundness up to 80% with respect to the component of the three undulations per revolution.

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To detect an angle of a wooden grain is indispensable for an automatic filling process of wooden surface by using industrial robots. This paper describes an image processing system which detects the angle by using an ITV camera, a digitizer and a personal computer. A new method which is based on a weight of the ratio of length to width of the grain of wood is applied to improve the performance of detecting the angle. From experimental results, it is clarified that the system detects the direction of the grain of wood with accuracy of three degree without special lighting.

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The purpose of this study is to observe an ideal design principle with the characteristics of generality, practicality and computability. In this study, the attention is paid to topology which has a metric space concept in itself and the design knowledge is organized in the metric space. In the previous paper, the mechanism of function operation is modeled mathematically. In this paper, a mathematical model of conceptual design process is deduced and convergence policy to generate the design solutions is discussed from the viewpoint of a metric in function space. And a methodology of generating the component structures which satisfy the required functions is deduced based on these mathematical models. This methodology is a kind of generate and test methods, but it is distinct by paying attention to the metrized function space in searching for the starting point and refining the hypothesis. This paper also describes a computer system developed and applied for mechanical field.

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The present paper deals with a method of detecting tool flank wear, tool fracture and chatter vibration, continuously in process of a cutting operation. A detecting system made by combining an adaptive filter and a neural network is proposed and is verified its effectiveness by using acceleration signals recorded during turning operations. An autoregressive model is fitted to an acceleration signal by applying an adaptive filter and then the autoregressive parameters are recognized by using a neural network. An autoregressive model in front of the neural network makes the neural network compact and a learning convergence faster. Acceleration signals are recorded during turning of medium carbon steel (JIS : S45C) with a piezoelectric sensor mounted at the top of a tool holder. As results of simulations on a computer using the actual acceleration signals, which correspond to tool flank wear, tool fracture, chatter vibration, useful detections of abnormal conditions are achieved and an effectiveness of the method is confirmed.

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This paper shows : that the geometrical analysis leads to a physical meaning of the compensation coefficient Ki ; how the compensation coefficient Ki and Ci are influenced by changing the thermal capacity and material of the column part, through several experiments. As a result, Ki is the product of an equivalent length from the heat source neiborhood decided by machine shape and the coefficient of linear expansion of material. The experimental value of Ci disappears with the progress of time.

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This paper examines the initiation mechanism of the damping capacity of turning tool. Turning tool is treated as the beam on elastic foundation. Parameters of the model elastic foundation are estimated from the experimental result of the frequency of free damped vibration. In the next place, the magnitude of damping energy is calculated from the friction resistance and the relative slip between tool shank and elastic foundation during both tangential and vertical vibrations. The calculated result of damping energy agrees well with the experimental result of the damping capacity qualitatively, in the changes of clamping load and surface topography. This result indicated that the damping capacity of turning tool system is mainly caused by the relative slip at tool shank.

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Machining of high-performance materials hitherto remains a major challenge in production. Cutting some of those materials by the self-propelled rotary tool is evaluated in this paper with respect to tool wear and tool life. Experimental results show that the rotary tool, characterized by the tangential motion of the circular cutting edge, enhances tool life far longer than the conventional one in turning a metal-matrix composite. Crater wear hardly occurs in rotary cutting of a titanium alloy and a high manganese steel. The inclination angle of the rotary tool is found to be an important factor which controls the relative motions between the tool and the work (chip), and hence tool wear.

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In this paper, plunge grinding techniques are proposed and investigated for high efficiency and high quality, in which the speed ratio of workpiece to wheel is continuously controlled with grinding time and in which the speed ratio and the infeed rate of wheel head are continuously and simultaneously controlled. Main conclusions are as follows ; (1) The speed ratio should be continuously decreased in infeed state and continuously increased in the early stage of spark-out state for improvement of surface roughness without increasing wheel wear. (2) In simultaneous control of speed ratio and infeed rate, the speed ratio should be increased in lower infeed rate stage for improving surface roughness. (3) The ideal grinding process of high efficiency and high quality can be established by means of continuous and simultaneous control of speed ratio and infeed rate.

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Microstructures and microhardness of TiC films coated on WC-Co cemented carbides by CVD and PVD (ion-plating) processes were investigated by transmission electron microscopy and Vickers hardness testing. The microstructure of CVD films is granular. On the other hand, that of PVD films is columnar and each of column has strong preferred orientation. The interdiffusion between substrate and coated material was observed in CVD films by EDX analysis. The microhardness of PVD films are much higher than that of CVD films. This is considered to be mainly due to the existence of residual stress in films. High compressive residual stress in PVD films can be expected from the computer simulation by TRIM-code. The result, of the simulation shows that energetic Ti and C ions are introduced into deposited film as interstitial atoms over a depth of 3 and 6 nm, respectively, in PVD process. The growth process of a film is proceeded by two simultaneous processes. One process is pile-up of Ti and C atoms on the substrate, the other process is injection of energetic Ti and C ions into deposited film.

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Tribology and micro-dynamics of a one-axis stage mechanism guided by a rolling ball guide, which achieved nanometer positioning, are studied. The force-to-displacement relationship consists of three displacement regions. In the first region of less than 100 nm displacement, the balls of the guide act as a linear spring. In the third region of over 100 μm displacement, normal rolling takes place. The second region has characteristics intermediate between those of first and the third. Static and dynamic regional transitions between these three are studied. Changes of the characteristics are measured for different positions and different load pressures. The force-to-velocity relationship of the guide is measured. Suitability of the rolling guide to fine positioning is discussed.

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This paper deals with the theoretical verification for the accuracy average effect of LMBG system using the load distribution formula derived in previous paper in the case where Gaussian shape misalignment is forcedly given to the one of the tow rails composed of the system. The load distribution and the maximum distribution load in the system and the guiding accuracy of the table, the effect of preloading etc. in accordance with the table movement are calculated. The obtained conclusions for the accuracy average effect are quantitatively described as follows. (1) When the misalignment width is smaller than the block length of the LMBG, then the ratio between the table displacement and the misalignment height becomes from 1/40 to 1/8. (2) In the case of the greater width than that, it becomes from 1/8 to 1/4. (3) When the misalignment width becomes infinity, that is, the rail is set quite parallel to the other, then it becomes 1/2.

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The present paper concerns a man-machine interface system for realizing the communication of a rather difficult information, which is unable to represent by the numerical method, such as an emotion of the artist. Since the emotion is expressed by action rather than word, the pattern of the tact movement for conducting synthesizer has been controlled by constructing the detecting and processing systems in real time. The tact, which is the most important input device has been made with high sensitivity of variation of speed without any effect from the swing directions, range and speed. The processing system has the sensitivity for detecting the degree of skillfulness, and then by using this parameter, the present system can conduct the synthesizer in the best condition corresponding to individual operators.

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This paper identifies axial stress decrease of six bolts attached to a rotational body. For each bolt head a distance from a sensor probe is measured while the rotational body is under rotation. A characteristic parameter representing a bolt head and a flange deformation is calculated for each bolt from the measured distance. Three types of diagnosis problems are dealt with by a multi-layer neural networks approach. A set of characteristic parameters and the number of hidden layer's neurons are changed and their effects on diagnosis performance are investigated. It turns out that the total of six bolt head deformation parameters are useful for the diagnosis, yielding low failed-safe and failed-dangerous probabilities provided that the number of hidden layer's neurons are suitably determined. The neural network gives better diagnosis performance than Bayes' discriminant function approach.

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The stresses caused by axial deflection of hydroformed bellows were generally calculated by shell theory solution or energy solution. In both cases, the calculation model of the bellows will be simplified and the thickness of the bellows convolutions will be assumed as a uniform thickness plate. And calculation solutions were often improper compared with experimental results. Since the sectional thickness of hydroformed bellows is different at outer side of bellows or inner side of bellows, a finite element method was applied to get the stresses caused by axial deflection of the bellows in this paper. The calculation stresses indicate that the thickness difference at OD and ID is very delicate to the stresses. Therefore, this paper proposes that the finite element method will be effective to estimate the accurate stresses caused by axial deflection of bellows, because the ratio of OD thickness and ID thickness can be reflected in the calculation easily.

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The Linear Approximated Equation (LAE) of the rotational vibration of a pair of spur gear, which was introduced in the 1st report, has a big advantage that the analytical solution of the equation can be obtained simply. In this report, the solution of vibration of the LAE, is then derived by analytical method, and by using this result, the effects to the vibration by the tooth profile error, rotational speed, static load, and contact ratio of the pair of gear, are also analyzed. It is found that the effect to vibration by the contact ratio is following a certain regulation. The authors applied this analytical solution to estimate the vibration of gears, the result agreed well with the result calculated numerically by the exact nonlinear equation of the vibration.

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A study is presented of measuring method for flat form error using a 2 D least square serial two point method. This method is extensively improved on a serial two point method. Consequently, this approach can compensate the measuring errors which are caused by fluctuations of four displacement sensors implemented on a measuring head. Further more, accidental errors which are involved in the measuring values are reduced by least square method. In this paper the following results are revealed by experimental analysis. (a) Measurement values obtained by this method sufficiently coincide with those obtained by laser interferometer. (b) Measurement accuracy is achieved to be sub-micrometer.

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Recently many trials have been proposed in displacement measurements using optical methods, and various apparatus based on optical triangulation are available on the market because of their simple and clear characteristics. In these apparatus a PSD (Position Sensitive Device) is used for the detection of displacement. However, the relation between the displacement of the object and output signal from the PSD is not linear. Therefore the output signal has to be corrected by an electric circuit for detecting the true displacement. In this research a new method is proposed for measuring displacement which utilizes a PD (Photo Detector) and a non-linear density filter instead of a PSD. This method brings linear relation between the displacement of the object and output signal from the PD. For the realization of a practical system, the output uniformity of the PD and the non-linear density filter are examined from the view point of design and producibility. Experimental results by a prototype apparatus verify the principle of this method has satisfactory linearity.

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This paper proposes a displacement measuring technique for detailed noncontact mapping of the interior geometry of pipings. The technique, which is based on the optical triangulation measurement, employs a laser-beam scanner to measure displacement in all radial directions. In order to achieve high precision measurement with this technique, three algorithms that calculate the displacement from sensor output are introduced and experimentally compared. The results clarify two problems : (1) the characteristic curves obtained using the technique are non-linear, (2) the curves differ slightly with respect to measuring direction. An algorithm that calculates the measured displacement by using a characteristic curve in the corresponding direction enables high accuracy measurement. The measurement accuracy of the experimental system is evaluated to be ± 0.2 mm in the range of 33-42 mm radius. A pipe interior geometry mapping system utilizing this technique with computer-managed data-taking and graphic display is also described. Its effectiveness is shown by the experimental results.

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