A new approach of modeling is put forward for expressing functions of clutch and brake directly, and their functional models are proposed in this report. Rotary motion is the most important type of motion for transmitting the kinetic energy, so many rotary parts and apparatus, for example crutch and brake, are used in most of machines. It is difficult to model function of the rotary element directly without relying on its structure by the conventional modeling approaches, for example the finite element method. The basic concept of the proposed approach is introduced, and the functional models of the hydraulic clutch with multiple plates, the clutch with vibration absorbing mechanism, the disc brake and the band brake are presented. Simulation results verify validity and usefulness of the proposed approach.

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Both self centering path and abnormal vibration orbit of a floating sun gear shaft in a star type planetary gear train which were observed in the experiments are numerically simulated with a simple dynamic model. The model is composed of a floating sun gear with three degree of freedom x, y and θ and meshing springs with backlash which support the sun gear. Effects of the gravitational force and applied exciting torque are also considered in the model. Equations of motion are solved by the Runge Kutta method under the conditions that a frequency of applied exciting torque is very small to obtain the selfcentering path, or it is equal to a torsional natural frequency of the model to obtain the abnormal vibration orbit. The simulated results are in good accordance with the experimental ones.

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The present paper shows a damage identification method of truss structures using a flexibility matrix which can be constructed from several low degrees of natural vibration frequencies and modes. The damage location in truss structures is detected from the change of the axial strain component in each truss member under virtual load before and after damage. The present method is verified through numerical examples of plane truss structures. We examine the effect of several factors on the identification of damage location, i.e., the effect of the number of vibration modes, the number of measurement degrees of freedom and measurement errors.

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A sphere placed in the enlarged conduit vibrates chaostically. A newly-found flowmeter consists of a enlarged conduit, a sphere, side plates set on both sides of the sphere, a stopper plate and a frequency detector. Fundamental studies on the flowrate characteristics were performed by adopting water, salt-water, and glycerin-water as working fluids. It was found that flowrate characteristics, i.e. relationship between frequency of the sphere and the flowrate, were proportional and the flowmeter was good enough to practical USe. It was ascertained, as a result, that the distance between the sphere and the stopper was the most important factor influencing to the flowrate characteristics of the flowmeter. Moreover, flowrate characteristics in the regions of the low and the high distances were independent of density and viscosity variation of the working fluid adopted within the limit of this experiments. The authors expect to apply the flowmeter to the practical engineering fields.

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In this report, the vibration system of 6 blades per shroud is analyzed by the transfer matrix method to show inherent characteristics of this construction of blades. As a result, it is proved that the tangential vibration is governed by two fundamental factors, one is the longitudinal flexibility of shroud, which gives the sequence of out-of-phase vibrations of blades from 1 node to 5 nodes in relation to the frequency, another is bending flexibility of shroud, which gives the sequence of outof-phase vibrations from 5 nodes to 1 node. The former fully governs the vibration behavior in the lower blade height region. The latter predominates in the higher blade height region, however, the effect of longitudinal flexibility of shroud still remains in this region and produces an irregular sequence and mode shape of out of-phase vibrations of blades.

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We established a 3-dimentioal simulation method for the vibration of bogie-track system and discussed about the effect of several factors regarding corrugation of rail in the previous report. We propose an improved simulation system to check the effects of surface irregularity of both wheel and rail in this report. The simulated results shows that the vertical irregularity of rail or wheel generates combined lateral and torsional vibration of rail and lateral slip vibration on curved tracks, and that the effects of lateral irregularity of inner rail are not so much. Those results are useful for survey the cause of corrugation of rail.

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Evaluation parameter of magnetic damping characteristics is needed for the mechanical design of structures located in a high magnetic field. In this paper, the coupling intensity parameter is proposed as an evaluation parameter of the vibration with magnetic damping. To verify that the magnetic damping characteristics are represented by the coupling intensity parameter, experiments and numerical analyses were performed. The conditions were obtained to keep the two parameters unchanged, namely the coupling intensity parameter and the time constant ratio of the eddy current and structure, using the dependence of the coupling intensity parameter. Since the damping charac- teristics of these cases agree very well, it is confirmed that the coupling intensity parameter and the time constant ratio are the evaluation parameters of the vibration with magnetic damping.

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A vibratory feeder of electromagnetic type is a typical transportation device used in automatic weighing processes. As existing feeders are driven by feedforward control so-called a "firing angle control", the driver can not cancel the effect of sudden disturbances. In this paper, we consider how to apply a feedback control to such a feeder system with the standard trough. First, we introduce a 2-degree-of-freedom PID controller to the feeder system. Next, it is confirmed through experiment to improve the transportation capability and the transient responsibility of the feeder system by using 2 d. O. f. PID control. Finally, we also propose the feedback system when parameters of the feeder system have been changed by using other troughs.

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In this report, first, the nonlinear equations of motion of a horizontal one-link flexible robot arm are obtained by use of the mode functions of a cantilever beam with a mass. Then, the algorithm of the desired signal planning of the joint angle for the purpose of the reduction control of residual vibrations of the flexible robot arm is derived by use of the initial and final conditions of the flexural displacement of the flexible link and the constraint conditions of the desired signal of the joint angle during the acceleration and deceleration terms as well as the linearized equation of motion of the flexible robot arm. The rotation control system of the flexible robot arm is constructed with the desired signal planning for the joint angle and the PD controller. Furthermore, the numerical simulations of the rotation control of the flexible robot arm have been carried out, and it is confirmed that the residual vibrations of the flexible robot arm can be effectively reduced by the present desired signal planning for the joint angle.

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This paper presents a new hyperplane design for sliding mode control using a linear parameter varying (LPV) plant model of active magnetic bearing system with gyroscopic rotor. We first extended the formulation of frequency shaped hyperplane design approach for LPV plants. Then, an actual turbomolecular pump system which has a overhung rotor contruction with gyroscopic effect is modeled as an LPV plant. The VSS control structure is derived for a single parameter dependent case using LPV plant model of the AMB system. The designed hyperplane for sliding mode control has a time varying structure with parameter variation. We carried out experiment using an actual AMB system and obtained good results.

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We discuss bending and torsional vibration control of the 6-stories flexible structure. In the case where they consider structural control like high rise building, it is required to design a controller to have good control performance and simple designing for cutting down on personnel. So, we apply sliding mode control that is nonlinear robust control theory. Adopting this theory, control system design becomes very easy, and it takes too short time to design. However this controller is done by state feedback in general way, and it is difScult to do. Because it's few cases that sensors are placed in all stories. For this, sliding mode controller should be designed with output feedback, so we designed two output feedback sliding mode controller by using minimum error excitation method. The first is constructed by only nonlinear control inputs, and the second is done linear and nonlinear input. And, we investigated their performance using such controllers with numerical simulations and experiments. Consequently, we explain design methods and control system design constraints, and characteristics for flexible structural control.

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This paper proposes a method for controlling the bending and torsional vibration of a flexible structure using Ha based optimal control. For this propose, we make a reduced order lumped mass model expressed by 3-DOF systems, considering the first three vibration modes and neglecting all the other high frequency modes. These neglected modes are regarded as unstructured uncertainties in the design stage. To prevent spillover instability caused by neglected mode, a modeling method based on the occurrence of uncontrollability and unobservability realized structurally at the nodes of the vibration modes is applied. Then, a static state feedback controller is designed based on the reduced order model and the approximate knowledge of the unmodeled uncertainties. The first three vibration modes of the flexible structure are controlled using a hybrid dynamic absorber. The discrete model and the controller design are verified through numerical simulations and experimental studies.

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This paper presents a method of disc-pole assignment for the design of robust control of flexible structures. The proposed method achieves a pole assignment of the controlled modes to a specified circular region in the complex plane and simultaneously obtains robust stability of the closed-loop system for important residual modes. The inverse bilinear transformation is used to obtain the conditions for assigning the poles to a specified circular region in the complex plane, and the proposed robust control design problem is formulated as a nonlinear optimization problem subjected to these conditions. The feasibility of the design method is examined by numerical simulations.

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This paper describes the attitude control problem of a flexible parameter varying spacecraft. Considered herein is the spacecraft consists of the main rigid body and some flexible solar paddles which rotate at the orbital rate in order to generate more electricity. In this case, the interference characteristics of the elastic vibration of the paddles and the attitude motion of the body changes depending on the paddle angie. Therefore, the attitude control system of such spacecraft becomes parameter varying. This paper is intended to establish the systematic robust control synthesis procedure for this problem by applying fixed controller via μ synthesis. Capability of the methed is investigated by the numerical study using the model of the ETS-VI spacecraft.

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This paper aims at proposing a new simultaneous optimum design method of structure and control system: such as several types of mechanical systems equipped with vibration control system in order to suppress the structural vibration of the mechanical system. When the proposed method is applied to the design of a structure-control combined system, the closed loop pole assignment of the lower order model of the combined system is specified in advance as a design requirement. Proposed method is constructed from two steps: in the first step, output feedback control system is designed for the initial structure in order to realize the specified closed loop pole assignment; and next step, structure and control system design parameters are simultaneously optimized to minimize the objective function subject to constraints on the pole assignment. Scalar objective function is defined as a linear combination of several measures of the optimality of structure design and control system design. According to the proposed method, the closed loop pole assignment of the lower order model is preserved through the iterative optimum design process. The effect of the proposed method will be shown by the numerical simulation results of the cantilever beam design example. Not only structural configuration but also control system are successfully optimized under the objective function minimization.

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High speed operation is required for industrial machines equipped with belt driving systems. The belt is, however, subject to a speed limitation barrier due to the occurrence of bending mode vibration resonances caused by machinery error, e.g., pulley eccentricity. To combat these resonances of the linear system, the parametric excitation method providing the belt tension fluctuation is proposed through the concept of the open loop vibration control theory. This analysis considers two types of fluctuation excitation featured by the frequency synchronized with one or two times the pulley revolution. The former is the most effective whereas the latter imparactical. The analytical results which are verified by well tuned experiments look promising.

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This paper presents a method of micro-vibration control of milling machine heads by use of vibration absorber. The principle used in the paper is different from usual absorbers. In the present absorber, an auto-tuning vibration absorber is presented in which the absorber create anti-resonance state. When the anti-resonance is used, the damping has to be significantly small, so it is difficult to suppress higher modes. To suppress higher modes, the present article uses autotuning magnetic damper. It damps higher modes, but it also increase first modal vibration. Then a method of optimal auto tuning control is presented in which both principal and higher modal vibrations are suppressed. Experimental tests are carried out for a real milling machine, and cutting tests are also performed.

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Traditional methods of structural design for vibration suppression are mostly with aim of avoiding resonance by changing natural frequencies of the structure. In other words, the purposes of these methods are to reduce vibration of specific frequencies. In this paper, we propose a structural design method for vibration suppression with aim of reducing vibration transfer properties over a wide range of frequency. For this purpose, the H_∞ norm, which is described by a descriptor formulation to deal easily with structural variables, is employed as a performance index. Matrix inequalities are formulated to evaluate the H_∞ norm in changing structural variables. A numerical example of a 3 D truss structure demonstrates the effectiveness of the proposed method.

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Experimental investigations were carried out on the characteristics of air flow noise for practically used heat exchanger tube banks. The tube banks are usually composed of bare tube, solid fin tubes or serrated fin tubes. For clarifying the air flow noise characteristics, the experimental data without resonant condition are used. The test tube banks were installed in the duct connected to a silent wind tunnel. The whole experimental setup was installed in an anechoic room. Sound pressure emitted from each test tube bank was measured by microphones on the duct wall and at the duct outlet. The experimental results were used to evaluate its RMS value, dominant frequencies and coherence against flow velocity for each kind of test tube banks. It is found that the rms pressure level of the airflow noise for each test tube bank is proportional to the 3rd power of flow velocity, and the acoustic pressure coefficient is mainly dependent on pitch-to-diameter ratio and tube bank depth. Thus, the airflow noise is concluded to be predicted by the acoustic pressure coefficients when they are experimentally determined for various tube banks used in industry.

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The vibration analysis using a holographic interferometer is a very useful method for analyzing the dynamic characteristics of machine elements. However, there is a limitation that the method can not measure large deformation. On the other hand, the method based on the moire topography have been proposed for solving this problem. However, there are also some problems peculiar to optical measurements. Because the moire method is based on the shape measurement, the displacement of an object can not be directly measured. We should grasp the trajectories of movement of the measuring points in the case of measuring displacement of the vibrating object with large amplitude. In this paper, a system which can measure the displacement of the vibrating object with large amplitude is proposed using the inverse-transformation for the central projection and estimating the trajectories. The experiment results show that this method is useful for the measurement of the object's displacement by the vibration with large amplitude.

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In the present paper, a spatial position sensor of new type for virtual catch ball system is proposed. In the virtual catch ball system, it is necessary to obtain spatial positions of the ball and the glove. For such a spatial position sensor, requirements are not only low cost but also wide measurable area and low noise. Several spatial position sensors which have already been developed do not satisfy those requirements. The authors' newly designed spatial position sensor is of simple structure and attains the above goal. The static and the dynamic examinations were made on the characteristics of that sensor, and it was found that the sensor has desirable characteristics. The performance Of the sensor is also discussed through the experimental results.

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In this paper, the method of monitoring of development of crack of structural member caused by dynamical load by angular velocity sensors using vibratory gyroscope is proposed. The one story structure having the test column with the artificial crack was oscillated at the base, assuming ground motion. Then, the test column took the repeated bending moment and the crack at the tip of artificial one was devoloped. The two angular velocity sensors using vibratory gyroscope were installed at the same distance from the center of crack. By the measurement of angular velocities, the bending curvature of material were able to be measured. Then, it is possible to measure the development of crack in material undertaking dynamic load, because a development of crack gives the change of moment curvature dramatically. Through the experiment, it was proven that the proposed method is effective to find the development of crack in material taking dynamical load.

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In the previous paper, the authors proposed a new mass measuring method under vibration like moving conditions. The mass measuring system used in the proposed method has the multi channel measuring devices of which dynamics are different each other. The principle of relative dynamic compensation which the authors have proposed to compensate the difference in channel dynamics of a linear measuring device is successfully applied to the mass measnring system under vibration like moving conditions. It is verified through simulation and experiment that the application of relative dynamic compensation is effective to improve the measuring accuracy.

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Recently, many new potential uses of advanced telerobotic systems have been explored, such as a computer networked robotics and a teleoperation on a WWW browser. The business communication channels and not the exclusive channels undergo large variation of the time delay. Therefore, it is impossible to achieve high performance over the entire operating range with a single robust LTI controller. Provided that the time delay is measured on line, it is desirable to use controllers that incorporate such measurement. In this paper, the design of the time-varying H_∞ controllers incorporates to adjust to the current time delay is discussed based on the framework of the gain scheduling. The validity of proposed method is confirmed by the simulation and the experiments using a directdrive master-slave system.

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As more and more physical based models are being used by the industry not only to improve reliability but also to shorten design cycles. Computer simulation with finite element model (FEM) plays important role in physical modeling technique. For the sake that there are always some differences in physical parameters from those of real structure, which is in a sense dealt as damage. The paper contributes the approach to detect the inconsistency between the real structure and the FEM efficiently, with Learning Vector Quantization (LVQ) neural network using the frequencies and Modal Assurance Criterion. Method for the detection of structure damage in wide range is studied and the preprocess of the training data is proposed to increase the detection accuracy.

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The present paper proposes a new design method in which a controller acquires the required performance automatically. Two important tasks of the control designer are the creation of a simulator of the plant dynamics and the determination of the evaluation of the controller. A three layered neural network of 4-inputs and 1-output controls the plant. The proposed method requires little knowledge of difficult control theories. Genetic algorithm (GA) evolves the neural networks to enable the control of nonlinear systems. The evaluation method originally proposed in this paper is very simple and easy to understand, so that it can be used even by non professionals working in the field of control. In order to demonstrate how to apply the proposed method, the present paper analyzes the load swing suppression of a crane system on a cart. Simulations reveal that the neurocontroller has higher performance than the linear quadratic regulator (LQR) with respect t settling time and robustness. The neuro-controller is able to suppress load swing even in environments that exceed design specifications.

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Recently, we have been demanding products that satisfy personal tastes. In these days, it is extremely important to make a human sensibility model and then build up a technology system for applying human sensibility to various fields in engineering. In this paper, a human sensibility model for musical chords is studied. The model that uses an artificial neural network is constructed by ccnsidering the structure of a cochlea that analyzes sounds into frequency. The musical chords that are composed of three or more musical tones are inputted into the neural network, and a set of the sensibility information that characterizes "cheerfulness-gloominess", "thickness-thinness" and "stability instability" is outputted. After training the model, the following results that agree with the knowledge of psychology and physiology are proved. 1) Some hidden units for "cheerfulness- gloominess" and "stability instability" are influenced by the critical bandwidth of musical tone frequency, and furthermore they have "Tonality". 2) For "thickness thinness", there is a unit that distinguishes musical tones by frequency.

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A dynamic model of the vapor compression refrigeration cycle is presented and examined with experimental results. The model is simple lumped parameter model so that the simulator based on the model can compute the responses in 1/3 of real time. Then the simulator can be readily used to design refrigeration cycle and its controller. The comparisons of simulation results with experimental data prove that the model simulates the cycle in qualitative sense, but contain some inaccuracy due to the simplifications.

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This paper deals with an autonomous action mode change in a behavior based learning of the mobile robotic system which is composed of two mobile robots consisting of a crawler and one DOF arm. The task is to carry a long bar horizontally along a compound road with keeping the barsupport distance constant. We propose an on line learning method "STL" (S-Temperature-based Learning). During the learning process, the robotic system can build up the state categorization in terms of two-dimensional sensory data (support length and support inclination). The robotic system can transit seamlessly between the learning process and the task-achieving process according to the internal state of the robotic system that is controlled by the S temperature introduced in to the STL. We show the effectiveness of STL by hardware robot experiments.

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This paper discusses a transit motion of a planar enveloping grasp with friction point contacts. We first formulate the kinematics and dynamics of the enveloping grasp on the assumption that Coulomb friction is applied at each contact point. The conditions for static determinancy of the enveloping grasp are derived based on the linear complementarity problem. We also show the relation between the static determinacy of the enveloping grasp and kinetic friction. Finally the conditions for the feasibility of a continuous motion by the enveloping grasp are presented.

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Recently, motorized equipment is required in order to support ADL (Activities of Daily Life) of the elderly. Authors are developing mobile type walking support systems. In this development, we understood the requirement for the assistance in standing-up and sitting-down motion is very important. We started to study about the elemental technologies of standing-up and sitting down motion assisted by upper body support arm (which is used for mobile type walking support systems). This paper describes the study on the support arm trajectory during this assisted motion. We developed a program to analyze the load acting lower limb joints in the motion. Using experimental data of supporting force, joint positions, and ground reaction force, joint torque was calculated in some trajectory patterns. Means to evaluate performance of the arm trajectory were obtained.

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The role of the tangential force acting upon the finger during tactile perception was experimentally studied. Although the tangential force is usually dealt in regard to the smoothness of the surface and the sensation of a protrusion is often related to the stimulus in normal direction in haptic interface, we believe that the tangential force is indispensable to generate the sensation of a protrusion. We performed the experiment using a virtual protrusion for the investigation. The virtual protrusion is the sensation, as if there is a protrusion on the fiat surface, generated by using ultrasonic vibration. The experiments using five to ten subject showed that the sensation of the virtual protrusion is dosely related to the vibration conditions. Based on the experimental results, the mechanism of generating the sensation was dynamically analyzed. The results showed that the tangential force is important to perceive a protrusion clearly although the tangential force cannot make the sensation of a protrusion alone.

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Magnetic bearing has been widely used to support rotor without physical contact. Since power motor has the similar configuration of magnetic bearing, a self bearing motor was considered and reported. This has both functions of rotating motor and magnetic bearings. This paper introduces an application of this motor to an artificial blood pump. A thin PM type self bearing motor has the capability of controlling χ and y direction and of giving rotating torque. Other three degrees of freedom are passively stable. In this paper, electromagnetic field analysis is apply to clarify the passive stable problem of the PM rotor using finite element method. An experimental setup is made and tested to confirm the proposed thin PM type self bearing motor. The result shows high feasibility of the use of the nonpulsatile type artificial heart.

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Animals have various muscular as power souses and they, living in the gravitational environments, have very similar basic muscular arrangements in their muscular arrangements reflecting differences in their locomotive life styles. We have reported that the coordinating muscular activities among the three pairs of antagonistic muscles contributed to the output force direction control, in all round (360°) direction, the force/position control and the stiffness control at the endpoint of the extremities. In the present paper, relations between the differences in the muscular arrangements in animals and the differences in the characteristic differences in their locomotive styles were analyzed in terms of functional anatomy and of control engineering. The results obtained that the muscular arrangements in animals was reflected in their locomotive styles. All animals had the essential muscular arrangements to realize the force and the stiffness properties at the endpoint of the extremities.

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The project, such as new product development, consists of various non deterministic jobs. Therefore, when we plan a new project, we examine the project characteristics in tems of cost, time, result quality and so forth. We often express a project as a stochastic network such as GERT. By this network model, we can analyze model parameter influences that will affect the model characteristics. In case of general GERT networks, theoretical analysis is difficult. Though Monte Calro simulation technique is powerful for the analysis, it has a week point. Namely, we cannot examine characteristic gradients; that is, partial differentials of the characteristic values with respect each network parameter. This paper proposes a new method, which consists of simulation and theoreticaI technique, in order to estimate network characteristic changes and their gradients.

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A robust optimal design method based on the minimax regret criterion is proposed to determine equipment capacities of energy supply systems so that they are robust economically against the uncertainty in energy demands. Equipment capacities and utility contract demands as well as energy flow rates are determined to minimize the maximum regret in the annual total cost while satisfying all the possible energy demands. This optimization problem is formulated as a kind of multilevel linear programming problem, and its solution is obtained by repeatedly evaluating lower and upper bounds for the maximum regret in the annual total cost. Through a numerical case study on a cogeneration system, it is shown that determining equipment capacities appropriately is more important under uncertain energy demands rather than certain ones. It is also shown that the ratio of power generating capacity to total power supply capacity decreases with an increase of the uncertainty in energy demands.

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A C- shaped constant force spring is made of pre stressed material and offers the advantage of constant tension and is being made ill various sizes, suitable for a variety of applications (for example, extension spring, motor brush holder, power feed, retracting and restoring mechanism). Essentially this spring consists of a coil of fiat spring material which has been given a heavy forming operation so that when unstressed it takes the form of a tightly wound spiral This spiral is placed on a drum. When a load is applied, the spiral uncoils. The load is practically independent of deflection. In this report, the mechanism of constant force and states of deformation are analyzed by using a large deformation theory. Moreover, an experiment is carried out to confirm the applicability of the proposed theory. The experimental results agree well with the theoretical estimations.

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The Tooth form factor of spur gear during working is described the product of the tooth form factor Y_Fa, the stress correct factor Y_sa, and the contact ratio factor Y_ε, according to the new standard JGMA 6101-01 based on the ISO standard proposal. As the results examined to the relations between form factors of various pressure angle, addendum, teeth, and shifting, the nearly linearlike laws are founded. Therefore, we propose the approximate algebraic formulae to estimate the form factors during working, which are consisted of the product by the working form factor of standard gears, using 14 teeth each others and pressure angle 20°, and the 6 parametric factors.

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It has been established to calculate the torsional rigidity of the strain wave gearing with the use of three-dimensional finite element method. Therefore at designing the gearing, it has been able to presume the effects of changing the shape or size of structural elements in the gearing upon the torsional rigidity. Then from the standpoint of looking for increasing the torsional rigidity of the gearing, numerical values were obtained by a computer about the effects of gap between each of structural elements on the torsional rigidity of the gearing in this study. In this paper, two kinds of gap are considered. One of them is the gap between ball and race of wave generator on minor axis. The other is the gap caused by coning of flexible spline. And this paper describes the results obtained from the numerical calculation.

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As the traction drive works under the high traction oil, in small slip ratio, and sometime accompanied with skew, the surface fatigue failures of the traction drive rollers are different to that of gears and bearings. In this research, fatigue tests of traction rollers are performed under the conditions of different load, slip ratio and skew angle. The effects of running condition on the fatigue lives of traction rollers are clarified considering the surface crack growth and wear. A higher slip ratio will make a lower fatigue life, but skew will lead to a higher fatigue strength because of the severe surface wear, which diminishes tile surface crack length, and the mechanics condition, which makes surface crack grow difficultly. For evaluation of the effects of such as slip ratio and skew on the fatigue strength of traction rollers, a new method is put forward in which the relationship between the surface temperature index and fatigue life is used instead of S-N curve.

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A new viscosity measuring system was designed and set up employing Rayleigh light scattering and a photon correlation technique using a diamond anvil high pressure cell. Two kinds of experiments were attempted. The one was the measurement for dilute suspensions of polystyrene latex spheres in liquid lubricants and a W/O emulsion. Correlation functions induced by BrownJan motion of small spheres in the lubricants were observed and the viscosities were obtained whose measurement time was one tenth shorter than that of falling body method. The other experiment was the measurement for 5 P 4 E (polyphenyl ether) and DOP (dioctylphthalate) without mixing polystyrene spheres. Very weak but observable correlation functions concerning structural relaxation were observed and the viscosities of solidified lubricants (about 10⁹ Pa·s), obtained in very short time by introducing shift factor for relaxation time, were consistent with those extrapolated from data of falling body method.

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Hard B-C-N mixed films were deposited by radio frequency (RF) sputtering using both hexagonal boron nitride (BN) and graphite (C) semicircular tareets. Vickers hardness, nano-indentation hardness and microwear resistance were evaluated. (1) The hardness of B-C-N mixed film is higher than that of C-N and B-N films. New hard B-C-N films were obtained under proper bias voltage and flow rate conditions. (2) Nano-indentation hardness showed similar results as Vickers hardness. Nano-indentation clarified the value on the hardness of the thin film, although Vickers hardness was influenced by the hardness of the substrate. (3)Microwear tests using an atomic force microscope demonstrated the excellent microwear resistance of B-C-N material element mixed film.

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In this study, the new angle control method to reduce the scatter band of clamping forces has been developed. The present method simultaneously loads a bolt with torque and compressive force, and measures torque and angle. The friction coefficients, the snug point and the spring constants of the bolted joint can be accurately evaluated during tightening process. Thus, the scatter band of clamping force in the elastic-region can be reduced within the error of 10% under oil free or lubricated conditions by the present method. The present method have high reliability and never loss tightening efficiency. It is possible to apply the present method to the plastic region tightening.

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A new ultra-fine piercing in which an SiC fiber of 14 μm diameter was used for a punch had been developed. For the sake of a widespread application of this process, the following should be clarified. They are; (1)discussion concerning about results in various conditions, (2)an applicability to various materials, (3)changes of process parameters and tool wear in continuous process and (4) understanding of piercing mechanism. Therefore process parameters such as punch speed and location to be pierced shoudl be controlled and the process should be conducted automatically. Furthermore the measurement of small piercing force and small punch stroke is necessary in order to monitor the process configuration and understand the pierching mechanism. In this report a control and measurement system applicable to the ultra-fine piercing was developed. A personal computer generalizes the whole system. When data are collected, accuracy, preciseness and reliability were improved under the consideration of characteristics of equipment and those of sensors. Obtained piercing force vs. punch stroke diagrams were sufficiently accurate and reproducible. It was clarified that with increase of an aspect ratio (foil thickness/punch diameter) the maximum piercing force to hardness increases because a material deforms severely. An efficient length of a fiber punch was estimated to be about 150 μm by a compression test of the fiber punch. A fiber punch kept sound even if it was applied repeatedly more than 120 times by the normal stress of 4 GPa. Besides it kept sound if the excess stress of 15 GPa was applied.

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A flexible and incremental sheet metal bulging method using a high speed water jet has been developed for the small-batch manufacture of non-symmetrical shallow shells. The computer operations-controlled bulging machine performed a wide range of sheet metal shaping on complex shapes, for example, pyramidal shells, shells of the frustum of pyramid, shallow pans and embossed panels. An approximate calculation method for the bulging height and the strain distributions of the shell was proposed, using a plane strain deformation model and momentum theory of hydrodynamics. The prediction for the shell of the frustum of a quadrangular pyramid was reasonably good agreement with experimental values for the annealed aluminum sheet.

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A method for refining grains near the surfaces of metal workpieces using hot shot peening is proposed to improve the surface properties of the workpiece. In this method, the grains are refined due to plastic deformation generated by the hit of many shots under hot working conditions. A model experiment using two shots is carried out to examine the effects of the amount of deformation, the processing temperature and the interval of the hit on the grain size. In the experiment, the workpieces are stainless steel SUS304, carbon steel S25C, mild steel and commercially pure copper. By means of peening with many shots, the global surface layer successfully attains to the fine grains.

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This paper deals with the effects of free abrasive grains added to grinding fluid in grinding. Austenitic stainless steel SUS 304 and sintered silicon nitride Si₃N₄ were ground using a cBN and a diamond metal bonded wheel, respectively. Alumina grains were used as free abrasive grains. The grinding force and the finished surface roughness were examined. It was clarified that in SUS304 grinding, free abrasive grains added to fluid acted effectively as loading-free agents on cBN grains without increasing the grinding force. Therefore, grinding efficiency was improved by 2-4 times. While, in sintered silicon nitride, free abrasive grains reduced the increase rate of the grinding force because they acted as dressing agents.

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Based on the present investigation, a computer-aided female screw grinding method without the form dressing process is proposed, in which a standard-shaped grinding wheel independent of the final hellcold is used. The method uses a simple conical or plain wheel, without limitations on diameter and base angle. The wheel axis is set three-dimensionally at the computed optimum angle of inclination comprising the tilt and swivel angle components of the planned helicoid and wheel. The optimum angle of inclination is determined through simulation of the grinding process and an investigation of the optimum angle of inclination that will give the minimum geometrical error. Through the aid of a computer assuming several geometrical shape of grinding wheel and generation experiments, it is shown that the present female screw generation method is effective and the generated female screw is more accurate than that obtained by normal female screw grinding method.

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Ductile mode grinding can be applied to ceramics if the grain depth of cut is decreased. In this research, single grain grinding experiments by using a pyramidal diamond tool have been carried out in order to clarify the ductile brittle behavior for 4 kinds of sintered ceramics. The results are as follows. (1) For the ground grooves of ceramics, shallowing effect by elastic recovery is not recognized. (2) The ratio of height of pile up peak to groove depth decreased with increasing maximum grain depth of cut _gn. (3) While the formation of ground grooves changes from ductile mode to brittle mode with increasing _gm, the pile ups of both sides of ground grooves coexist with chipping in the transition region. (4) In the brittle mode region for SiC and Al₂O₃, the actual groove depth was larger than the set value. (5) With ductile mode grinding, the height of formed peak between two grooves approximately agrees with the geometric value.

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This paper proposes a new slicing technique with OD-Blade that can improve the machining efficiency and accuracy, and make a remarkable decrease in quantity of the working fluid compared with the conventional slicing method. In order to accomplish these requirements, authors have developed the vibration slicing method with the atomized working fluid and executed the fundamen- tal considerations. The results obtained from experimental and theoretical considerations as to this method are noted as follows: (1) When the flow velocity of the atomized working fluid increases, the grinding force shows decrease regardless of the non-vibration and the vibration slicing methods. (2) The wafer roughness and the chipping produced in the edge of the slicing groove as the machining accuracy are equal to the conventional supply method of the working fluid when supplying the atomized working fluid. (3) It is possible for the vibration slicing method with the atomized working fluid to bring out the decrease effect in the waste water.

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