In this paper, the effects of the physical characteristics of a golf club head are investigated on its performance in order to develop a superior club head. Here the physical characteristics are the magnitude of the moment of inertia and the depth the center of gravity. And the performances are the release velocity, the spin rate of the ball and the size of the uniform velocity ratio. In the numerical analysis, several kinds of club head are modeled with different moment of inertia and depth of the center of gravity. For every club head model, the ball is hit from various impact points, and the release velocity, the spin rate and the size of the uniform velocity ratio are calculated. The results are as follows. When the moment of inertia increases, the spin rate decreases and the release velocity increases. The size of the uniform velocity ratio also increases. When the moment of inertia about the horizontal axis or the one about the vertical axis increases, the width in vertical direction or the one in horizontal direction increases, respectively. When the ball hits at the heel side or toe side, the bigger the depth of the center of gravity is, the bigger the spin rate is. The sensitivities of the physical characteristics of club head on the performance, also, can be obtained.

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The vibration behavior of the crankshaft in operation is complex to simulate because there are many contributing factors, some of which are varying, oil film stiffness and damping, coupled vibration of the rotating crank train and cylinder block. This paper describes a new method of analyzing the nonlinear vibration of rotating crank train, in which calculations are made of using nonlinear equation of motion. This method uses stiffness and mass matrices of the component parts, which have been extracted from the finite element model using in-house software. The coupled vibration of the rotating crankshaft and cylinder block is calculated by means of time history response analysis, in sonsideration of the non-linearity of the oil film stiffness, damping and friction. The accuracy of this calculation technique was demonstrated by comparing the calculated results with the actual vibration measured with LASER equipment.

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This paper studies transfer characteristics of the counter-rolling: a rotational eye movement subjected to tilt of the body. We identify a discrete time-varying model of the counter-rolling by using Kalman filters. The identfied model predicts precise values of angular displacement of the eye as a function of tilt of the body. To characterize the transfer characteristics, we derive the time-invariant system from our time-varying model fixed at a moment and define the time-varying impulse response from impulse responses of the time-invariant system as a continuation of each fixed time-varying model. A series of the time-varying impulse response qualitatively characterizes time-varying transfer characteristics of the eye. Irregular responses of the eye are also characterized by our method.

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This paper proposes a method to suppress the vibrations of a machine-room-less elevator. Up until recently, elevators have needed a machine room. Now a machine can be installed in the hoistway because the Building Standard Acts have been amended. We have developed a machine-room-less elevator which has the machine in the pit of the hoistway. The rope is longer and number of pulleys is greater than in previous elevators. This tends to cause vibration in the cage. This vibration, in turn, deteriorates the ride quality. To suppress vibration, the design parameters must be optimized such that the transfer function between these disturbances and cage acceleration has a minimal value. The masses, spring constants, and damping coefficients are considered as control parameters, and optimized in the best design. The spring constants and damping coefficients of the thimble rods are important to suppress vibration. In experiments we reduced cage vibration to two thirds that in our previous design, and thus, improved the ride quality.

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The dynamic analysis of link structures, including elastic vibrations, is presented. The multi nodes element including the large displacement is developd. This element is based on the theory of the finite rotation, and considers the geometric stiffness. The stiffness matrix and the inertia matrix are obtained from FEM model by the theory of the Guyan reduction including the large displacement motion. In this paper, we explain the theory of this element and show some examples of analysis.

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A refined solution procedure is presented for analyzing in-plane free vibrations of a rotating circular plate. Equations of motion and boundary conditions are derived considering the effect of initial tensions due to the rotation. The equations of motion are solved exactly by power series expansions. Frequencies and stress distributions of the circular plate are presented and the characteristics are discussed comparing the results by the present theory with those by the classical theory.

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This research deals with nonlinear dynamics of a rotating rigid magnet levitated above a high-Tc superconducting (HTSC) bulk, Motion of the rotating magnet in the radial and axial directions were investigated theoretically by using analytical expression of electromagnetic force obtained by "the advanced mirror image method". Analytical and numerical results show existence of combination resonance due to nonlinear coupling between whirling and vertical motion of the magnet. The resonant frequency of rotation is given as the sum of the natural frequency in the horizontal and vertical directions. At this resonance, the whirling motion becomes quasi-periodic, having the harmonics with both the driving and natural frequencies, while periodic motion at the natural frequency appears in the vertical direction. Stability analysis shows that this resonance occurs if the eccentricity of the magnet is larger than a certain critical value. Experiments for spinning motion of the magnet were carried out, and combination resonance predicted in the theory was clearly observed. Nonlinearity in forces can thus have significant effects on dynamics in application of HTSC bearings.

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In this study, it is shown that 2 D.O.F.chattering model were considered and this model can explain the mechanism of chattering. In this model, the effects of friction forces between cutting edge and workpiece or cutting tips were considered. Friction forces are varied by not only cutting force but also change of relative velocity between cutting edge and workpiece or cutting tips. In this analysis, also the effects of nose R of a cutting edge and multiple regenerative effect were considered. From the results of analysis, it seems that the friction force of shear force direction is more effective to chattering than the friction force of cutting force direction. And it is obvious that 2 D.O.F.chattering model with friction forces gives coupling to the cutting system. In this paper, it is explained that how 2 D.O.F.chattering model was derived and the necessity of friction force considering relative velocity between cutting edge and workpiece is proved.

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This paper deals with the polygonal deformation phenomena of rolls in a reversible hot plate leveler of the steel making machine experimentally and analytically. The plates leveled by rolls with polygonal deformation become so called defective products because the profile of deformed roll is transferred to the surface of plate. From the measurements of deformed rolls, two kinds of polygonal wear were found. Then, from the vibration measurement of a hot leveler in actual operation, natural frequencies of the hot leveler were determined and the process of the polygonization of rolls was observed. Finally, the authors analyzed a simple model theoretically, regarding the polygonal deformation phenomena as unstable vibration of the hot leveler system caused by time retardation accompanied by wear on the surfaces of rolls. A good agreement between experimental and theoretical results was also confirmed.

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This paper investigates a feedback control to follow free giant swing motions which were derived by the optimum trajectory planning method. By evaluating eigenvalues of the transitional error matrix on the Poincare plane, it was proved that free giant swing motions do not have autonomous trajectory stability. Stable giant swing motions are realized by a proposed configuration control, in which the actuated joint torque is controlled such that the measured state variables follow the reference configuration relation as a function of angular position of the passive joint. We made a gymnastic robot with no actuator at the first joint. Using the 2-dof gymnastic robot, it was shown that stable giant swing motions of type B and C can be realized by the configuration control.

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Due to the need for an increase in rotational speed of hard disk spindles, disk flutter has become one of the largest disturbance for the head positioning servomechanism in high track density recording. As means of suppressing disk flutter, we propose a squeeze air bearing plate, which is positioned close to the rotating disk, and investigate the flutter-suppressing effect of the bearing both experimentally and theoretically. It was found that the squeeze air bearing plate with a radial width of 15 mm, angular length of 90 degrees, and bearing gap of 170 microns can decrease the disk flutter near the leading edge of the bearing to less than one third of the original disk flutter.

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It has been a problem in some hospitals that operations using surgical microscopes for brains and eyes bacome more difficult due to microvibrations of the microscopes caused by human wolks and building equipment such as air conditioning machines. For a practical solution to it, a microvibration control system was developed, in which an active dynamic vibration absorber using a small mass of 0.34 kg driven by an electromagnet and an accelerometer were collocated for vibration control in each direction. The system was attached on the point of the arm of the microscope. A direct velocity feedback control law was developed for the microscopes having various dynamic characteristics corresponding to their attiudes. Furthermore an active-passive switching law was developed to manage large vibrations of the microscopes due to doctors' handling of them. Tests showed that the microvibration control system was effective and reliable enough for real application.

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Belt driving systems applied to many kinds of equipment for industrial machinery encountered a vibration resonance problem due to the increase of the operational speed. In order to reduce this resonance vibration, we proposed parametric excitation feed-forward control using torque fluctuation. A drawback is not being able to apply it for multi-exciting sources. Alternative ideas are proposed in this paper, which are bang-bang feedback control using sign function based on variable structure system theory. These methods are nonlinear control to fluctuate belt tension using bang-bang switching defined on displacement-velocity phase plane of detected belt vibration. The stable conditions in terms of control phase were detected. The control effects were confirmed theoretically. As a result, these bang-bang feedback control methods are effective and have many practical advantages for usage.

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Belt driving systems applied to many kinds of equipment for industrial machinery encountered a vibration resonance problem due to the increase of the operational speed. To reduce this resonance vibration, we proposed parametric excitation feed-forward control using torque fluctuation. A drawback is not being able to apply it for multi-exciting sources. The alternative ideas were proposed in previous paper, which were bang-bang feedback control using sign function. That method were nonlinear control to fluctuate belt tension using bang-bang switching defined on displacement-velocity phase plane of detected belt vibration It was proved both theoretically and numerically that the methods were very effective to reduce transverse vibration of belt driving system. In order to confirm the control effect experimentally, a test device, which consisted of three pulleys (driving, idler and tension pulley), was established. As a result, this bang-bang feedback control is very effective and has many practical advantages for usage.

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Since a direct-drive(DD) motor system doesn't use the reduction gear, the structure of the servo system can be simple and stiff. On the other hand, in the DD system, the disturbance torque directly influences the accuracy of the control system. The high feedback gain is effective and important for reducing the influence of the disturbance. However, it easily makes the control system vibratory. Therefore, the servo gain has to be lowered for assuring stability, and this causes the influence of the disturbance large. In this study, we aim to realize the high gain feedback control and the DD motor system using an ER fluid damper is developed. By applying the ER damper to the DD motor system, it is possible to obtain the mechanical damping and to realize a high servo gain in the motion control. Finally, the effectiveness of the proposed system is confirmed experimentally.

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With progress of technology in recent years, gigantism and complication such as high-rise buildings, nuclear reactors and so on have brought about new problems. Particularly, the safety and the reliability for damages in abnormal situations have become more important. Intelligent control systems which can judge whether the situation is normal or abnormal at real time and cope with these situations suitably are demanded. In this study, Cubic Neural Network (CNN) is adopted, which consists of the controllers possessing cubically some levels of information abstracting. In addition to the usual quantitative control, the qualitative control is used for the abnormal situations. And by selecting a suitable controller, CNN can cope with the abnormal situation. In order to confirm the effectiveness of this system, the structural vibration control problems with sensory failure and elasto-plastic response are dealt with. As a result of simulations, it was demonstrated that CNN can cope with unexpected abnormal situations which are not considered in learning.

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For a step reference input, pneumatic servo systems are designed in such a way that there is a compromise between stability and rise time of the response. For practical use, we have adopted some ideas to improve the response. One example is the operation of a pneumatic on/off valve by electrical power higher than the nominal power for an initial short period of time. Based on the above example, we developed a fuzzy virtual reference generator that can adjust the reference input to the fuzzy controller adaptively by fuzzy rules to improve the rise time of the response. The applicability of the proposed method is confirmed by experiments using vertical pneumatic servo system.

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Based on genetic algorithms, we propose a practical design method for robust nonlinear controllers of uncertain nonlinear system. First, we show how to combine the genetic algorithm with the control design. In the proposed design method, the techniques of genetic algorithms are used to circumvent the difficulties of calculation of minimax solutions. Next, we illustrate by simulation the reliability of the proposed method through a simple example. Finally, we demonstrate its applicability by tackling with the flight control problems of landing in a windshear.

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A Michelson interferometer has been constituted and applied to the measurement of lubricant spreading on a magnetic disk surface. Performing image processing on the fringe patterns formed by the interferometer, the lubricant thickness, as well as the spreading behavior can be investigated. This method provides complete line profiles in two dimensions and permits direct observation of the spreading phenomena, in contrast to the conventional point-by-point scanning method. To improve the measurement accuracy, a fringe following technique and a noise suppression technique were introduced. The fringe following technique successfully prevented a fringe drift over the visual filed and thus suppressed the pseudo phase shift caused by the drift. The spatially fixed noise due to non-uniform laser beams and flaws in optical components was also efficiently suppressed by the noise compensation method. From the calculation of multiple beam interference in a stratified medium, it is found that the sensitivity is dramatically enhanced if the lubricant is coated on the back side of a disk instead of the front side. Utilizing this advantage, a novel scheme was employed to give maximum sensitivity, in which lubricant was observed through a glass disk whose front surface was coated with anti-reflection film and whose back surface was sputtered with the proper thickness of DLC. The enhanced resolution attained by the new scheme was experimentally confirmed by observing the lubricant on the front surface and the back surface of the glass disk.

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In this study, we have developed a bilateral telerobotics system for construction robot using virtual reality. The system consists of a servo-controlled construction robot, two joysticks for operation of the robot from a remote place and a 3-degrees-of-freedom motion base. The operator of the robot is sitting on the motion base and is able to control bilaterally from a remote place. The role of the motion base is to simulate the realistic motion of the construction robot. We proposed, in this study, a new method of master-slave control in order to control hydraulic actuators, which were used for actuating the construction robot. The availability of the proposed method was examined by experiment and simulation and thus the validity of the method was confirmed.

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This paper presents an anthropomorphic robot hand called Gifu Hand II to be used as a platform of robot hand for robotics rearches. The Gifu Hand II has 5 fingers driven by servomotors built in hand. The thumb has 4 joints with 4 degrees of freedom (DOF), the other fingers have 4 joints with 3 DOF, and two axes of joints near the palm cross orthogonally at one point like the human finger. It can equip 6 axes force sensor at each fingertip and a developed distributed tactile sensor with 624 detecting points on its surface. The design concepts and the specifications of the Gifu Hand II and the basic characteristics of the hand with force sensor and tactile sensor are shown. These show that the Gifu Hand II has a high potential to perform the dexterous object manipulation like the human hand.

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In order to care bed-bound and disabled people without charging both patients and nurses with physical and mental stress, we have developed a robotic prototype of a human-assisting system, called the Human-Assisting RObot (HARO). It is requested that patients enjoy their daily life and cares without giving physical and mental burdens to nursing people. There are two ways to care the patients. One is to conduct the cares by an intelligent robot autonomously, another is to be performed by a human-assisting system. Since we believe it is necessary to combine humman's cognitive capability and robot's power, we have developed a robotic prototype of a human-assisting system as a wearable power assisting system including human's intention, skill and cognition. In this paper, the concepts based on the practical experiences of care, system design, developed robot and the exprimental results are described.

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This paper reports on a method of identifying some macro parameters in the control system of human dynamics. In particular we focused our attention on disturbance in the center of gravity in human stance posture control system as the research theme. In the first seep, we constructed a system to measure the human's sway of center of gravity. A subject stands on one foot according to the indication of a display unit and the sway of center of gravity is measured two-dimensionally. The Characteristics of stance posture control system were then identified using the lateral sway of center of gravity and input signal. In the second step, a mathematical model for stance posture control system by considering the human internal construction. Finally was proposed some control parameters of human inside condition were estimated by comparing with the characteristics and mathematical model obtained from the system identification. The result indicated that we can indirectly obtain a dead time, and several feedback coefficients in the posture control system.

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FRR(fiber reinforced rubber) is a flexible material which consists of elastomer and helical cord. The purpose of this study is to propose a simplified mechanical model for an estimation for extensional stiffness of a FRR column. At first, FEM analysis is performed for the FRR column. The mechanical behavior of the FRR column depends on the helix angle, fiber diameter and pitch circle diameter of the helical cords. The incompressibility of the elastomer, which is located at the center of the FRR column, has also an important effect on the mechanical behavior. Secondly a mechanical model is proposed on the basis of the FEM results. The simplified model reasonably explains the deformation behavior of the FRR column.

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Reduction of extensional stiffness in helical cords during bending fatigue was investigated carrying out some experiments, FEM analysis and mechanical analysis. The cords were constructed of stranded glass filaments and Resorcinol-Formalin Latex, and were used in synchronous belts. The stranded glass filaments were de-bonded and the extensional stiffness was reduced after the bending-fatigue. The FEM results showed that the reduction of extensional stiffness could be explained by the initiation and extension of the de-bonding in the cord. A simplified mechanical model was proposed to explain the reduction of extensional stiffness of cords.

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A control method of finishing dimensions of a helical concave conical gear, called center-ball measurement, is newly developed. The tooth surface of the concave conical gear is different from that of the conical involute gear, which is concave compared to the tooth surface of the conical involute gear. So the over-ball measurement of the conical involute gear can not be used at it is, but can be applied to a special measuring conditions. This center-ball measurement is based on the over-ball measurement of the helical conical gear. But in this method, the measuring ball, which is composed of two hemispheres, must be used. So the over-ball diameter can not be measured, but a center-ball diameter, which is the distance between two ball centers, can be measured instead. In this research, first the measuring condition is established. Second the center-ball diameter is obtained analytically. Finally, the center-ball diameter is verified through experiments. The experiments prove that this method has opened a door to the control of finishing dimensions in hobbing and grinding of the helical concave conical gear.

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In this study, a new type of cylindrical gears has been manufactured by use of CNC hobbing machine. This paper presents a detailed investigation on various characteristics of the gears with curved tooth traces. The contact ratio are calculated. The limits of undercutting and tooth pointing are determined. And then, the contact characteristics of the mating gears are analyzed by simulating the generation process and mating motion. Different contact patterns are presented as examples to show the changes of the contact area under different mating conditions. The mating gear teeth contact with each other at a line when there is no errors and no crowning. Three methods for generation of crowned gear tooth surface are proposed. Moreover, the influences on the bearing contacts by manufacturing error and misalignment are investigated.

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This paper presents a study on tooth deflections and root stresses of helical internal gears with various standard pressure angles. The deflection and root stress of internal gear tooth with various standard normal pressure angles α_n due to a concentrated load were calculated by the three-dimensional finite-element method (FEM). On the basis of these caluclated results, approximate equations for the influence function of the tooth deflection and the bending moment factor on the critical section of the gear tooth were derived. The validity of these approximate equations was confirmed by comparing results by these approximate equations with those by the FEM. The load sharing factor, the load distributions on contact lines and the root stresses of helical internal and external gear pairs with various helix angles, face widths and numbers of teeth were calculated using the influence functions of tooth deflection and contact approach, the bending moment factors and the stress concentration factors for various α_n. The effects of design parameters on the load sharing factor, the load distribution and the root stress of these gear pairs were determined. Furthermore, the meshing position of maximum root stress of the helical internal gear pair was also determined.

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It is said that helical gears with bias tooth surface modification, a kind of three-dimensional modification, can secure quietness within the wide range of transmitted load, However, its theoretical grounds have not been clarified in the past researches. Helical gears with theoretical involute helicoid have the character that lowers mesh exciting force within the wide range of transmitted load when the transverse or overlap contact ratio becomes an integer. In this paper, the relationship between tooth contact condition and tooth stiffness in such gear pair is discussed. As a result, theoretical grounds for the effectiveness of the proposed three-dimensional modification are clarified. In addition, the way of designing three-dimensional modification to the helical gears that have the arbitrary contact ratio is proposed and the effect is examined by the theoretical analysis.

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A rake angle of cutting tool has a more influence for tool wear and accuracy of finishing surface, value setting of a rake angle is very important. But on the other hand not enough theoretical study has given to this actual rake angle during hobbing operation. Here we would like to show the change of actual rake angle caused by hob, workpiece data and cutting conditions with theoretical calculation. As a result, we found a lead angle more influence for a actual rake angle, and there is large difference between the right and left side in finishing surface such as large module hob.

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Friction loss of hypoid gears was studied in order to decrease the friction loss from a view point of lubricating oils and surface treatments. The tests results showed that the viscosity affects on the friction loss very much and showed that the higher the viscosity, the lower the friction loss in both of mineral oils and synthetic oils. It was also clarified that there is a suitable viscosity to minimize the total loss of a hypoid gear unit. Especially in the case of hypoid gears used in high loads, a synthetic oil decreases the total loss of a gear unit by about 25∼30% than that of a mineral oil. Moreover it seems that the surface treatments used here have little affect on the friction loss of hypoid gears.

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It is known that the adhesive were particles are the converted form from the transfer particles which grow between two sliding surfaces. For the continuous growth of the transfer particles, the shear fracture is supposed to occur at the inside of the bulk, which requests the shear strength of the interface being higher than that of the bulk. In the present study, the authors have found out that this process is enhanced by the continuous supply of gold and silver atoms onto the sliding surfaces of Sn, Pb and Zn disks when rubbed against themselves. The reason of this phenomenon was supposed to be due to that the shear strength of transfer particles was increased by the inclusion of impurity metals (gold and silver) in the transfer particles.

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The study proposes a manufacturing method of aspherical Fresnel lens and dies with ideal lens profile. Conventional methods such as photolithography reveals low surface quality due to step-like cross-section and burr generation. In the study, the use of side cutting edge of a single crystal diamond tool allow Fresnel lens and dies to be manufactured with high optical efficiency. Ultraprecision Fresnel lens dies of 60 mm in diameter was created without any burr by using an ultraprecision turning center having 1 nm positioning accuracy and a diamond tool. The surface roughness of slopes in Fresnel lens grooves was 8 nm (peak to valley) in the radial and circumferential directions. Fresnel lens manufactured directly on an acrylic resin plate also shows disigned performance.

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Undeformed chip thickness may be smaller than radius of cutting edge at small feed rate when workpieces are cut by a finishing tool with large round corner. Therefore, in finish cut, sharpness of cutting edge has to be taken into consideration in cutting process. The purpose of this study is to find mechanism of cutting force occurrence at smaller undeformed chip thickness than radius of cutting edge. In this study, the effects of cutting edge radius both on cutting force and on burnishing force were investigated in orthogonal cutting. Furthermore, contact length between tool flank face and woprkpiece during cutting was measured in order to consider the relation between the burnishing force and the contact length. As a result, the conclusions were reached as follows. First, the following parameters very inversely as the nth power of undeformed chip thickness normalized by radius of cutting edge: (i) cutting forces per unit area of chip section, (ii) specific burnishing force defined as burnishing force divided by undeformed chip thickness and by width of cut, and (iii) specific burnishing length defined as burnishing length divided by undeformed chip thickness. Second, cutting force occurring on flank face of ploughing force is greater than excessive cutting force caused by reduction of rake angle on round face of cutting edge.

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This paper elucidates the formation mechanism of breakouts at the edge of workpiece in cutting of titanium aluminide intermetallic compounds. Furthermore, the relationships between the mechanical strength and the defects including the breakouts and cracks on edge and finished surface is clarified. The results obtained from this study are as follows: The breakouts are formed by propagation of the crack caused by lamellar structure of workpiece. Four-point bending tests in which two types of specimen are prepared, the cutting direction is at right angle to edge and the cutting direction is parallel to edge are conducted. The parallel-specimens are superior to the right-angled-specimen at the average bending strength. Although at the specimens which indicate low strength the breakouts or cracks are observed at the workpiece-edge, there are improvement of the strength by chamfering the specimens. The propagation of the cracks formed at almost right angle to cutting direction on finished surface relates to the strength.

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For developing age-hardenable, free-cutting aluminum-copper (Al-Cu) alloys that are environmentally friendly, the influence of silicon (Si) addition for chip breaking during lathe cutting was examined in comparison with the addition of conventional elements, lead and bismuth (Pb+Bi). Both Si and Pb+Bi increased the degree of chip breaking; in maximum, 10 times for the Si addition and 100 times for Pb+Bi addition. The increase in the chip breaking frequency due to Si addition was ascribed to the embrittlement of the alloy; Si particles act as crack initiation sites and accelerate crack propagation in the chip. However, chip breaking mechanism for the Pb and Bi added alloy was different; the lake face is covered with a thin layer of Pb and Bi and chips move on the rake face smoothly, leading to severe chip curling. A high performance of chip breaking due to Pb and Bi addition was attributed to resultant, large bending deformation that the chip receives

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A new process of tube ironing, the "Planetary Conical Rolling" (PCR) process, is proposed. A number of rollers rotate around the cone while revolving around their respective axis, preventing sliding friction which is the main cause of galling and breakage in the conventional ironing process. Additionally, a large deformation and a high pressure can be applied locally to the material under each roller because this process is an incremental process and the axis support cone is highly rigid. Taking advantage of these features to produce a hybrid tube, lap pressure welding by PCR process between aluminum alloy (A 5052) and pure copper (C1100) was discussed in this paper. From the measurements of bonding strength, it was found that the relative strength of outer tube against inner tube mainly affected the bonding strength. That is, high bonding strength was obtained when the relative hard tube was set on the inner side. Distribution of normal bonding strength in the axial direction was measured, which coincided with that of radial compressive strain in the outer tube. This is explained by the difference of plastic zone in both tubes depending on the material combination. Conclusively, in order to pressure-weld the dissimilar tubes by PCR process, it is necessary to give enough thickness reduction to the outer tube which is difficult to be deformed.

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Vibration of machine tools has induced some serious problems because of reducing surface quality and accuracy of a work piece and emission of noise in a machine shop. In the previous paper, we have developed a powder composite damper in order to improve the structural properties of machine tools. The powder composite damper has high damping vibration as well as high static stiffness. A C-frame type punch press with the powder composite could reduce noise and vibration. However, when this damper is used for a countermeasure of vibration on a machine tool, most suitable specifications of the damper cannot be grasped at the design stage. Therefore, in this paper, a simulation method for using the powder composite damper with suitable specification was developed and evaluated. Properties of the powder composite damper were made clear by experiment and FEM analysis. Next, a simulation method for using powder composite damper was established with forced vibration FEM analysis. The method was evaluated by using a C-frame type punch press. It is concluded from the results that the proposed simulation method was very effective for using a powder composite damper with the specification.

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A new type of job shop scheduling scheme is proposed in order to manage manufacturing system which has hierarchical structures. A system which consists of several system elements is identified as one independent system element and a job processed by the system elements is defined as a job for the system. Recursive propagation method, which is proposed by the authors in order to exchange information in the decentralized manufacturing system, is applied to the hierarchical job shop scheduling problem. Each system element notifies its action to the other system elements in the system and can know the change caused as a consequence of the action in the whole system. The feasibility of the methodology proposed is verified by computational simulations.

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Some kinds of dielectric fluids such as dibutyl decane-dioate generate jet flow between electrodes. One of the authors calls the fluids ECF (Electro-conjugate Fluids), which are considered as smart fluids. The authors propose a micro motor by making use of ECF. In our previous paper, stator electrode (SE)-type micro ECF motors have been reported. In this study, a rotor electrode (RE)-type micro ECF motor is proposed. On the RE-type micro ECF motor, some pairs of electrodes are located on the surface of a cylindrical rotor. The rotor can rotate with the reaction force caused by ECF jets. By making use of the ECF jet's reaction force, micro motors are easily realized. Also it is expected that RE-type ECF motors have higher power and higher efficiency than SE-type ECF motors. In this paper, fabrication of micro ECF motors having I.D. φ3 mm, I.D. φ4 mm, I.D. φ8 mm is described. Basic characteristics such as rotational velocity, load characteristics, output power and efficiency are experimentally examined. Also, mathematical models of the ECF motor are proposed and verified with experimental data. Finally, miniaturization characteristics and aging characteristics are examined based on the fabricated ECF motors.

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General Disign Theory (GDT), which was presented by Yoshikawa in 1979, holds the possibilities that the object can be also applied to creative arts field in addition to narrow sense artifacts, because the description of GDT is very wealthy in abstract-ability and generality. The purpose of this study is how the music creation process can be described by using GDT, and also researches the application possibilities to creative arts field of GDT. An expression requirement by a self-expression desire that was born from a composer's environment is generally symbolized on the form "music", and a performer interprets into the entity "sound" using above-mentioned music that indicates the attributes (pitch, dynamic and time value) of sound with the notation. In this paper, it deals with so-called "composition" which is the process form requirement to music. Generally, the creation processes of musical works in creative arts field are personal very much and most of the descriptions about process are ambiguous. By deducing various theorems about music creation process by using GDT, a clear description becomes possible. The gotten results don't have contradiction with musicology, and an application possibility to creative arts field of GDT is shown.

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