In order to achieve an automatic parking for a four-wheeled vehicle, it is necessary to consider back and forth motion before the final approach, as well as backward motion in the final approach. In this paper, a method to generate the path consisting of line segments, circular arcs, and clothoid arcs including the back and forth motion is presented. The method is derived by pay attention to a point that a middle goal selection makes an impact to a generated path which has shorter path length. By using the proposed method, the path is found easily for both reverse parking and parallel parking

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This paper describes a self-excited vibration of a Flow Dynamic Conveyer (FDC). The FDC is often used in a power plant and an iron works because of superiority in quiet compared with a roller type conveyer. The FDC consists of a trough and a belt, and the air is supplied from a lot of holes provided on the trough. A large vibration suddenly occurs when the flow rate becomes the critical value. In this paper, some measurements were performed in order to clarify the phenomenon. As a result, it was found that the phenomenon was the self-excited vibration based on the interference between two vibration systems such as the load·air-spring system and the trough·supporting system.

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In this paper, a gain-scheduling controller for automotive vehicles is proposed. This controller is to protect the vehicle from spin and realize the improved cornering performance. Since the vehicle unstabilization is mainly caused by the cornering force saturation of rear tire. This saturation is considered explicity in design by using LPV modelling method. And a gain-scheduling controller is designed based on linear matrix inequality (LMI) approach. Simulation shows that the vehicle stability performance is improved significantly as compared with robust control based on linearized model.

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Digital inpainting provides a means for reconstruction of damaged portions of an image. Although the inpainting basics are straightforward, most inpainting techniques published in the literature are only suitable for remarkable small portion or smooth color image. In order to avoid such shortcomings, we present a new algorithm for digital reconstruction based on combination of wavelet decomposition, Surface-based/PDE-based inpainting and texture synthesis. In which, wavelet transform at first decomposes the image into high frequency and low frequency level parts. Subsequently, CSRBF which is generally used for surface interpolation or PDE-based inpainting is employed for low frequency level and texture synthesis is used for high frequency level. It results in that not only slightly portion but also the common blotched image can be reconstructed with high quality. Especially, our algorithm makes many difficult cases for other methods possible.

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In practical applications, it is important to reduce the function evaluations in the simulation, and obtain the approximate optimum with high accuracy. To achieve these objectives, the integrative optimization system using the RBF Network (RBFN) and the Generalized Random Tunneling Algorithm (GRTA) is proposed in this paper. This system consists of three parts. (1) Construction of the response surface, (2) Optimization by the GRTA, and (3) Adding the sampling points. The RBFN is used to construct the response surface. The radius on RBFN, which affects the accuracy of response surface, is an important parameter. Firstly new equation for the radius is proposed, based on the examination of existing equation. Secondly a simple sampling strategy to obtain an optimum with high accuracy is also proposed. In general, the objective function and the constraints are approximated, separately. However, the optimum of response surface will often violate the constraints. To avoid such situations, the augmented objective function is utilized in this paper. Then the proposed sampling strategy is applied. Through typical benchmark problems, the validity and effectiveness are examined.

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For a rubber baseball, which is a baseball made entirely of rubber, the softness of the ball makes it very difficult to increase the coefficient of restitution (COR) of the ball-bat impact by modifying the stiffness of the bat. In order to direct modification of the baseball bat, precise analysis of the impact phenomenon is required. In order to establish a powerfull tool for analyzing the baseball-bat impact, numerical analysis programs based on the three-dimensional finite element method have been developed. After verifying the developed programs by comparing calculated and experimental results, the impact characteristics of an aluminum bat in collision with a rubber baseball were investigated precisely. The results show that the COR decreases with increasing impact velocity, and that the COR is greatly affected by the hoop rigidity of the barrel of the bat, which has a hollow shell structure. Moreover, at high impact velocities, the COR is maximized at an impact location about 600 mm from the end of the bat handle.

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Damper units, as well as several bushings, of vehicle suspension systems show asymmetry restoring force properties in response to their direction of stroke. A property prediction method for these components is helpful in vehicle dynamics development process. In order to develop the modeling method for these properties, we modified “the analytical method of equivalent linear system using the restoring force model of power function type”, which is one of the effective methods in nonlinear system analyses, and applied to these asymmetry restoring force properties. From the comparisons between the results from calculations and those from experiments, the validity of this method was confirmed.

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The crack arose during actual operation, in an impeller of large-sized blower, at the joint part of the main board and blade. For the purpose to clarify, this phenomenon, dynamic analysis and static analysis using the finite element method were performed. The analysis results showed that the cause of a crack of impeller is the stress which occurs owing to the deformation of the side board by centrifugal force. This deformation is wave like one which is same pitch as blade. Then, the structural modification by pseudo-inverse method was performed for the purpose of stress reduction. In this case, designer does not want the minimum weight optimum design but the minimum modification design. Pseudo-inverse method may modify the structure with the minimum distance in the design variable space to satisfy the stress restriction. Some cases are tried. When the design variables were 3 main parts thicknesses, those are main board, side board and blade, practical solution is deduced for 8 calculations to satisfy the stress limit with 10% weight increase.

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This paper deals with an excitation mechanism of the flow induced disk vibration of HDD. Since the shroud clearance is very influential factor in the disk vibration, we examined experimentally how the aerodynamic excitation force in the shroud clearance generates. A flow condition in the shroud clearance and the relation between the flow condition and the disk vibration were investigated. Experiments show that making the shroud clearance small leads to reduction of the excitation force and that the excitation force occurs mainly near the disk edge. The vibration amplitude of the disk has a relation with the Reynolds number on the shroud clearance as a characteristic length, so it is considered necessary to make the circumferential flow in the shroud clearance less turbulent for reduction of vibration of the disks.

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Wave motion of a liquid in a rotating, axially symmetric container undergoing a whirl motion is investigated. In the analysis, gravity is considered negligible and the liquid motion is taken as being axially uniform. Assuming that the liquid layer is thin, the equations of motion are simplified to one-dimension problem along the circumference of the container by shallow-water theory. The modal coupling equations including the nonlinear effects of the wave motion are presented by applying Galerkin's method. Periodical solutions under harmonic whirl motion, which give resonance curves, are determined by applying the harmonic balance method to the modal coupling equations. The wave height and the fluid force acting on the container obtained from the analysis are compared with the experimental results in the previous works. A good agreement is found between the analysis and the experimental results about the wave height profile and the magnitude of the fluid force by which the asynchronous whirl motion of the container is excited.

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Brushless DC motors, which are widely used in many household electrical appliances, require noise reduction to improve their functionality. Owing to the inevitable manufacturing and assembly errors, the vibration level in actual motors will often exceed the level assumed in design. In order to investigate the generation of electromagnetic vibration, we developed experimental apparatus which can measure the radial force and vibration of the motor. A feature of the experimental apparatus is to preset the amount of eccentricity of the rotor to the stator. We investigated the effect of manufacturing errors on electromagnetic vibration and obtained the following results : when the rotor and the stator are in an eccentric relation, the electromagnetic force is generated in the radial direction. The frequencies of the radial forces are affected by the number of poles, and their levels are proportional to the eccentricity. When the inside of the stator is elliptical, electromagnetic vibration is generated in the second mode. The frequencies of the electromagnetic vibrations are several times the number of poles, and their levels are proportional to the eccentricity and the circularity of the stator.

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Partial admission has been applied to the control stage of steam turbine because it produces high turbine efficiency at low loads. The shock load caused by partial admission generates excitation force on a blade, and the vibratory stress of the blade may become a cause of HCF (High Cycle Fatigue). Therefore, in designing a control stage blade of steam turbine, the vibratory stress caused by partial admission should be exactly predicted. Recently, ISB (Integral Shroud Blade) structure has been applied to not only the low-pressure end blade but also the control stage blade of steam turbine. Because the traditional analysis method based on experiments can predict only the vibratory stress of the grouped blade structure, it is indispensable to develop the general analysis method of vibratory stress caused by shock load, which can be applied to both of the grouped blade and ISB structure. This paper, first, presents the analysis method for the grouped blade and ISB structure to calculate the vibratory stress caused by partial admission. Second, the vibration response characteristics to shock load is explained, using some calculated results of simplified blade models. Finally, the response analysis is carried out for the actual grouped blade and ISB structure, and the results are evaluated from the viewpoint of blade reliability.

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In this paper, we propose a wavelet-based method to detect the discontinuities of the tangent stiffness of a hysteretic restoring force from acceleration data. The discontinuities of the tangent stiffness indicate that the system has suffered inelastic deformation. Therefore we can estimate the damage of the system to detect the discontinuities of the tangent stiffness. We confirm numerically and experimentally that the occurrence of the discontinuity can be detected. The experiment is carried out using the 5 th-story structural model installed by lead rubber bearing (LRB) with hysteretic characteristics of restoring force. The experiment results show that wavelet transform makes it possible to estimate the inelastic excursions to the elastic region, when a non-stationary wave is inputted into the structure.

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Orthogonal contributors in terms of both structural kinetic energy and radiated acoustic power are derived for the purpose of simultaneous attenuation of both vibration and sound. The orthogonal contributors are referred to as “vibroacoustic modes”. The vibroacoustic modes have eigenvalues and eigenvectors along with structural modes and radiation modes. The eigenvalues of the vibroacoustic modes indicate the vibroacoustic modes' contributions to the sum of the structural kinetic energy and radiated acoustic power. The eigenvectors of the vibroacoustic modes indicate the modal shapes of the vibroacoustic modes. The complex modal amplitudes of the vibroacoustic modes can be measured by filtering error signals from discrete structural sensors attached on a structure. It is found that the sum of the structural kinetic energy and radiated acoustic power can be estimated by the sum of the squared complex modal amplitudes of few of the vibroacoustic modes which have higher contributions (higher eigenvalues). This allows one to get a reduced order controller. To verify the validity of vibroacoustic modal control, numerical results relating to an isotropic plate in an infinite baffle are presented.

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This paper concerns the minimization of total acoustic power radiated from noise source. First, the authors focus that the acoustic power of the control source under the optimal condition for minimizing total acoustic power become zero. Then, the authors propose a method employing an active noise control in order to minimize the total acoustic power by investigating the acoustic intensity distribution pattern of the control source. This power reducing performance is verified on the basis of theoretical estimations.

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This paper is concerned with a new approach for avoiding the fictitious eigenfrequency problem in boundary element analysis of three-dimensional acoustic problems governed by Helmholtz equation. It is well known that, in solving without any care an external acoustic problem with internal sub-domains by means of the boundary integral equation, its numerical solution is violated at so-called fictitious eigenfrequencies corresponding to the internal sub-domains. The present paper proposes a new boundary element analysis to circumvent such a fictitious eigenfrequency problem by using dual boundary integral equation for nodal points on the boundary. One equation is the combined integral equation proposed by Burton-Miller. The other equation is the normal derivative boundary integral equation multiplied by the same coupling parameter as in the Burton-Miller expression. The quadrilateral element is employed in this study, and the Burton-Miller combined boundary integral equation is used at the middle nodes of element, while only the normal derivative boundary integral equation multiplied by the same coupling parameter is applied to the vertex nodes of element, and vice versa. The proposed approach is implemented, and its validity and effectiveness are demonstrated through numerical computation of the typical problems.

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This paper presents a new design sensitivity analysis based on the boundary element method avoiding the fictitious eigenfrequency issue in acoustic problems. The direct differentiation method is applied to the derivation of sensitivity formulas. In solving an external acoustic problem with internal sub-domains by means of the boundary integral equation without any care, is numerical solution is violated at the so-called fictitious eigenfrequencies corresponding to the internal subdomains. The present paper proposes a new boundary element sensitivity analysis avoiding such a fictitious eigenfrequency problem. This is based on the dual boundary integral equation, proposed previously by the authors, and the integral expressions are differentiated directly with respect to the design parameters. One equation is the combined boundary integral equation proposed by Burton-Miller and the other is the normal derivative boundary integral equation multiplied by the same coupling parameter as in the Burton-Miller expression. The quadrilateral element is employed in this study. The Burton-Miller integral expression is used only at the middle nodes of element, while the normal derivative boundary integral equation multiplied by the same coupling parameter is applied to the vertex nodes of element, and vice versa. The effectiveness of the proposed approach is illustrated through some numerical examples for three-dimensional problems.

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A target of our research is a conected two-pole-link mechanism with one controllable joint. The one link is long and the another one is short. The long link is jointed to the center of the short link with an actuated joint. We call the long link upper-body, and the short one lower-body. In initial condition, upper-body stands vertically and lower-body lies on the ground. This mechanism is expected to be able to move by swinging its upper body and rolling its lower-body, from that initial posture. In this paper, we propose some control laws and algorithms, for the model of this under-actuated mechanism, and give means for aplication to a actual experimental machine. And, we show results of the moving motions in experiments by actual machine.

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In this study, we propose an object-handing robot system with a multimodal human-machine interface which is composed of speech recognition and image processing units. Using this multimodal human-machine interface, the cooperator can order the object-handing robot system using voice commands and hand gestures. In this robot system, the motion parameters of the robot, which are maximum velocity, velocity profile peak and handing position, can be adjusted by the voice commands or the hand gestures in order to realize the most appropriate of the robot. Furthermore, the cooperator can order the handing of objects using voice commands along with hand gestures. In these voice commands, the cooperator can use adverbs. This permits the cooperator to realize efficient adjustments, because the adjustment value of each motion parameters is determined by adverbs. In particular, adjustment values corresponding to adverbs are estimated by fuzuy inference in order to take into consideration the ambiguities of human speech.

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In this paper, a prototype robot hand consisting of permanent magnet type stepping motors, gears and plate springs is developed, and the grasping force performance of the robot hand is investigated theoretically and experimentally. The robot hand is attached to a single-joint robot arm driven with a hybrid type stepping motor and a ball screw. In the theoretical analysis, the equations of motion of the system are derived, and the numerical calculations have been carried out. Then, it is ascertained numerically that the feedforward grasping force control can be well executed. Furthermore, the experiments have been carried out, and the excellent performance of the feedforward grasping force control is confirmed experimentally. Moreover, it is ascertained theoretically and experimentally that the hunting phenomena of the stepping motors are generated, when the operation time of the feedforward grasping force control is shorter to some extent.

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In this article, vehicle dynamics integrated control algorithm using an on-line non-linear optimization method is proposed for 4-wheel-distributed steering and 4-wheel-distributed traction/ braking systems. The proposed distribution algorithm calculates the magnitude and direction of tire forces, which satisfy constraints corresponding to the target resultant force and moment of the vehicle motion and which minimizes maximum μ rate (=tire force/friction circle) of each tire. Convexity of this problem is shown, so that the global optimality of the convergent solution of the recursive algorithm is guaranteed. This implies that theoretical limited performance of vehicle dynamics integrated control is clarified. The proposed algorithm is based on SQP (Sequential Quadratic Programming) and steepest gradient algorithm. Calculation speed performance of the proposed algorithm is shown in comparison with primal-dual interior-point method, which is representative optimization method. Furthermore, the effect of this vehicle dynamics control is demonstrated by simulation and experiment to compare with various vehicle dynamics integrated control methods.

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In this paper, a novel robust path tracking controller with tire distribution for 4WS/4WD vehicle is presented. The proposed control law prevents wheel force saturation by balancing four tire forces, while vehicle velocity is controlled so that it converges to the reference one as long as the required acceleration can be generated. If driving force is saturated due to high speed cornering vehicle velocity is automatically reduced by active control of lateral forces so that required centripetal force is decreased. Thus, the proposed method suppresses the vehicle trajectory deviation from the reference one. In addition, sliding mode controller assures the robustness with respect to the uncertainty of cornering power or road friction coefficient. Both tracking performance and robustness of the proposed method are shown through simulations.

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A method of optimal driving force allocation to the wheels of multi-wheel vehicles is proposed. Practical application of in-wheel motors to vehicles expands the capability of vehicle control and efficient drive. The determination of necessary driving force on each wheel is essential factor for efficient drive especially for multi-wheel vehicles with individually controllable wheels. Optimal driving force allocation to each wheel has been formulated by minimizing the slip loss done by all the tires due to ground contact. Solving the equations with the specifications of an eight-wheel vehicle under several conditions, optimal driving force allocation and the combination of optimal steering angles were obtained. The result of the numerical simulation was found to be useful for target driving force on each wheel for efficient drive.

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Investigations were made on the usability of hierarchical menu-driven vehicle touch panel display for multiple information system. The experiment to acquire one goal from sixty-four choices was performed for both with and without driving task using driving simulator. Tested menus are (breath^depth) 2^6, 4^3, 8^2 and 64^1. For the case of without driving task, usability of 8^2 is the best followed by 4^3. On the other hand, the goal acquisition time with driving task showed a decreasing difference between 8^2 and 4^3. Moreover, in considering subjective grading, 4^3 is the best closely followed by 8^2. Subjects feel 43 easier to use. This is mainly due to the ease of use in selecting the aimed sub-menu.

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In this investigation, a numerical procedure that can be used for the three-dimensional analysis of wheel and rail contact geometry is developed using the constraint contact formulation. The locations of contact points are determined for given lateral and yaw displacements of a wheelset when one-point contact is considered for each wheel, while these two displacements are no longer independent once the flange comes into contact with rail. A systematic procedure for predicting the flange contact point is developed and used for the initial estimate of the three-dimensional lead/lag flange contact analysis. It is shown that the location of the lead/lag flange contact varies in highly nonlinear manner for the change in the wheelset yaw displacement. Numerical results are presented in order to demonstrate the use of the contact algorithm developed in this investigation. The results obtained for a one-point wheel/rail contact problem shows good agreements with those obtained using the existing method that has been used in one-point contact problems. The method proposed in this investigation allows for predicting the location of lead/lag flange contact points. Furthermore, a simple procedure for predicting the location of contact point on the back of flange is presented.

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To lessen operation errors in case of the invisible machine operation, the information assistance system is considered. That is, if its invisible movement sign is informed to operators by some audio/visual/tactile devices, it is helpful for them to do more precise operation. This system is applied to the boom tilt operation of the rough-terrain crane. At first, the adequate device choice test has been tried by using the crane control simulator. The force feedback control lever, by which the boom acceleration signal is transformed to the force signal, is good for operators to guess the invisible motion. This force is varied in accordance with its acceleration. So, this system is varied for the real rough-terrain crane. Four professional operators have tried the tilt operation task ; this system has lessened operating errors on account of the assistance of the boom motion recognition.

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From the viewpoints of energy and cost savings, it is important to rationally operate water supply systems composed of pumps, piping, and reservoirs. However, it is very difficult, because nonlinear performance characteristics of pumps and piping, discrete performance characteristics due to the combination for on/off status of pumps, and daily operational strategies of reservoirs must be considered. In this paper, a two-stage approach to the performance analysis and optimal operational planning of a water supply system is proposed. At the first stage, the performance characteristics of pumps and piping are analyzed by the Newton-Raphson method, and are optimized with respect to the combination for on/off status and revolution speed ratios of pumps by the enumeration and nonlinear programming methods, respectively. At the second stage, the daily operational strategy of the system is optimized with respect to the storage level of a reservoir by the dynamic programming method. A case study is conducted to show the effectiveness of this approach.

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Impact characteristics of a cue in billiards are evaluated numerically by developing a simple method. It is assumed that the cue and ball are elastic and rigid, respectively. The displacement of the cue is evaluated by the finite element method and that of the ball is calculated by solving the equation of motion. The time variation of impact force is estimated by equating these displacements at contact point. The accuracy of the analysis is checked by performing a detailed finite element analysis and an experiment, in which a freely supported cue is hit with a swinging ball. It is shown that (1) the impact force and the ball velocity increase with increase in the stiffness of the shaft, (2) the contact period decreases with increase in the stress wave velocity in the cue, (3) with increase in the stiffness of the tap, the impact force rises rapidly, reaches a large maximum value and falls in a short time (4) the ratio of slip to rotation of a ball during the contact period increases with increase in the stiffness of the shaft and the tap and (5) a peak appears in the time variation of impact force for a soft shaft due to the metal screw in the middle of the shaft.

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This paper proposes a head-positioning controller design for hard disk drives using multirate sampled-data H^∞ control theory. Two types of upsampling-by-2 controllers have been derived by solving a mixed sensitivity problem, one is with exogenous inputs at the plant input side (Type A) and the other is with those at the plant output side (Type B). The controlled plant used here has a mechanical resonance at a higher frequency than the Nyquist frequency of a sampling frequency of the controlled output. As a result, it has been confirmed that Type A controllers are robust against aliasing of the resonance and that Type B controllers, which have the same features as conventional digital controllers using analog notch (band-eliminated) filters, attains a wider control bandwidth than that of Type A. Although the control system is affected by the resonance aliasing, a Type B controller has achieved higher positioning accuracy than that of Type A in a benchmark simulation of a hard disk drive with dual-stage servo mechanism.

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This paper describes the method of presuming the angle of moving direction of an electric wheelchair by reading information of RF tags put on a floor using a rotary antenna, which is fixed underneath the wheelchair, revolving constantly above RF tags of the floor at a turning point. Our primary intention is to make a detection system of direction angle using RF tags for a voice controlled electric wheelchair. The voice instruction cannot give smooth nor detailed controls with ease unlike the joystick control. Because the voice control system can use only a few discrete instruction words. Thereby to assist smooth indoor motion, we proposed here a new method of automatic correction of the direction angle measured by the above rotary antenna and RF tags. We demonstrated experimentally to detect and correct the angle of moving direction when the wheelchair passes over the turning point, which was found to give accurate orientations.

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There are many electric power generators employing dynamos. However, most of them require large mechanical energy input at a time to get large electric power output. This task is not easy for elders because of heavy load. Therefore, we aimed to develop a new ubiquitous power generator suited for light power input. In order to generate large electric energy with light force, we propose a new generator mechanism to store mechanical energy using a spiral spring and gears. Large mechanical energy is stored in the spring by iteration of light force input. We designed a mechanism which can store mechanical energy in the spring by rotating an input lever several times with light force. The energy is restored to rotate the dynamo at high speed to generate electric energy efficiently. While restoring the mechanical energy, reverse rotation of the input lever is avoided by the clutch. Analysis as well as experiment of the proposed mechanism was performed here for optimal design of gear train. As an application, a power generation device which generates energy from door motion is shown to see effectiveness of this mechanism.

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We propose a brachiation robot named Brachiator. Brachiator is able to swing like a real gibbon. The limbs of Brachiatior are designed to be actuated through the wires. However, the elongation and slack of the wires often arise and make it difficult to estimate the joint angles accurately, which has to be resolved to attain more stable brachiation behavior. In this paper we indroduce a vision system to improve brachiation behavior in real time. A stereo vision system is mounted on Brachiator that looks like a gibbon's face. We estimate errors between a model based trajectory and a real trajectory in implementation world from the images which the vision system captures during the brachiation behavior. Based on the vision-based error estimation as to the grasping position on the target branch, the trajectory of the behavior is adjusted in real time in order to realize successful brachiation behaviors. Experimental results showed that the proposed system reduced deviation of the grasping position of brachiation behavior as much as 40% compared with previous methods.

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In this paper, we have applied the analysis method for the robot manipulators to the evaluation of the manipulation ability of the human upper limb. The set of maximum hand force based on individual's muscular power characteristics were expressed in the six-dimensional convex polyhedron (Manipulating Force Polyhedron). The spatial characteristic of the manipulation ability of the upper limb in three-dimensional space was clarified by the visualization of the six-dimensional convex polyhedron using a new vertex search algorithm. In order to show the effectiveness of the proposed method, we compared manipulating force polyhedron with measured maximum hand force. The manipulating force polyhedron was calculated from measured maximum joint torque of the upper limb depending on joint angle and rotation direction. Our evaluation method will be useful not only for the evaluation of the manipulation ability of the upper limb but also for the development of equipment based on individual's muscular power characteristics.

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A problem of probabilistic vision-based multi-person tracking with a monocular camera in a cluttered office environment is addressed. In such a case, it is often difficult to obtain reliable measurements of the absolute position of a person on the floor plane due to the inherent uncertainty in depth. To deal with this problem, a novel measurement technique based on occlusion reasoning is proposed and combined with a standard particle filtering technique. This technique is based on the relative position of a person with respect to background objects. The effectiveness of the proposed technique is investigated in an experiment where two persons overlap on the image plane.

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The “Man-nen dokei”, that literally means a clock that works for ten thousand years, is a historic perpetual chronometer that was built in 1851 by Hisashige Tanaka, who founded the predecessor of Toshiba Corporation. It has six multifunctional clock faces and is crowned with a celestial globe that shows the positions of the sun and the moon. It is said that “Man-nen dokei” is one of the best works in Japanese traditional clock. Recently, it has been disassembled and restored in a national project as a one of the most original symbols of Japanese manufacture, so we investigated the mechanism of the “Man-nen dokei” in cooperation with the project. This paper shows the mechanism of the celestial globe and the Japanese traditional clock which is the main part of the six clock faces. Especially, we focus on (1) the mechanism for simulating the motion of the sun and the moon throughout the year in the celestial globe and (2) the mechanism for the movement of the “warigoma”, the ten square pieces, which show the time in the old Japanese temporal hour system.

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The “Man-nen dokei”, which is a historic perpetual chronometer, was made in 1851 by Hisashige Tanaka, who founded the predecessor of Toshiba Corporation. It has six multi-functional clock faces and a celestial globe. It is said that it runs for almost a year with just a single winding. Man-nen dokei was disassembled and restored in a national project. We investigated on the mechanism of Man-nen dokei in cooperation with this project. In this paper, we report on the mechanism of the power supply. As a result, from mechanism constitution of the power supply, we confirmed that maximum continual movable days of Man-nen dokei were approximately 225 days. But from the fusee steps and the double spring composition, it is thought that Hisashige's goal was to make it move for 1 year continually. The spring that generates the huge torque became necessary to make it move for 1 year, but it is assumed that the spring were wound just a little due to strength poverty of the wooden frame. Moreover, we think the composition of one fusee is a reasonable design to obtain necessary torque continuous operation with stability for 1 year, and the reason why Hisashige used composition of two fusees still remains to be unclear.

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We developed a new diagnostic method by using a laser beam from the point of view of remote diagnosis. Our method can be explained as follows : first, a tooth surface is irradiated by a zonal laser beam from oblique direction, and then an irradiated laser beam line is shifted along the height of the tooth according to gear revolution. The variations of the laser reflection between the initial and the present conditions are compared, and it can estimate a condition on the tooth surface such as normal or destructive wear, pitting, spalling, etc. To confirm the validity of our method, a pitting experiment was carried out, and at the same time the laser reflection was measured. As a result, the data of the laser reflection experiment revealed occurrence of the pitting apparent and early. Thus, it can be concluded that our method can accurately estimate the condition of a tooth surface and sufficiently assess the duration of the gear life.

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This paper studies the opening characteristics of aluminum bottles with screw caps. In order to examine the opening characteristic, opening experiments and measurements of friction coefficient and contact state between the bottle and cap have been performed. An analysis technique of estimating the 1st torque when unscrewing the cap is proposed in consideration of the experimental results. The estimation agrees with the measurement of the 1st torque in general. It is necessary to take the relation between the friction coefficient and contact pressure into consideration to improve the estimation accuracy. The influence rates of the seal part, the screw part and the skirt part to the 1st torque are about 60%, 25%, and 15%, respectively. It is obvious that the design space of the skirt angle needs to be reduced so that a stable value of the 1st torque can be expected.

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Improvement of lubricity between tool and chip or workpiece is essential for obtaining good cutting performances. In particular, the achievement of high lubricity is required in minimal quantity lubrication (MQL) cutting. MQL cuttings, however, have problems relating to low lubricity or low stability and, as a result, the introduction to practical cutting industry is limited. Then we examined intermittent cutting-face milling-experiments for aluminum alloy under flood fluid supply in order to clarify the problems. As the result, it was confirmed that the lubricity between tool and chip deteriorates as cutting probresses, namely, with longer cutting length. Then, to overcome the above problem, cutting tools with micro structured surface, that is, micro grooves were developed in the hopes that the grooves play the role as retainer of cutting fluid. A series of cutting experiments revealed that the cutting shear angle became larger and the cutting force became lower, as compared with the conventional cutting tool without micro grooves. This demonstrated that the micro grooves brought low friction to cutting tool surface. Furthermore, it was found that the newly developed cutting tool was effective for maintaining good lubricity in MQL cutting.

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Bolted joints are widely used to assemble various structures, and the conditions of bolted joints significantly affect the dynamic characteristics of structures. This problem causes the difficulties for designing precision machinery or earthquake countermeasures for structures. The aim of the present research is to clarify the contact surface conditions of structures with bolted joints from the microscopic aspect by tribological theory and to develop an estimation method of global dynamic characteristics of structures. First, the method to estimate the natural frequency and damping ratio of structures with bolted joints from the magnitude of tightening torque is proposed. The estimating process is divided into 4 steps, i.e., estimating, (1) tightening force from the tightening torque, and then step by step, (2) contact pressure, (3) contact stiffness and friction loss and finally, (4) natural frequencies and damping ratios of structures. The proposed method was actually applied to the plate and flange structures, and the natural frequencies and damping ratios were first estimated and then those were measured experimentally. It was shown that the calculated results are in good agreement with the experimental results, resulting in the verification of the usefulness and universality of proposed estimation method.

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The purpose of this paper is to clarify stall torque characteristic of 3K type traction drive CVT by considering slip ratio and spin effect at each contact point in the traction system. The 'stall torque' is in proportion to position of shift ring at low speed ratio condition. As a result, the experimental stall characteristics of the CVT almost agreed with theoretical ones with considering slip ratio and spin effect at each contact point with an elastic-plastic model based on EHL theory. In addition, the utility of the CVT as a 'torque converter' was discussed; the 3K type CVT can change its output torque by changing the position of shift ring even at the constant speed ratio condition. This paper proposed a new concept of torque converter realized by 3K type CVT with appropriately utilizing its stall characteristics.

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A circular arc slider with high flying height for optical disk devices is proposed in order to reduce the thickness of devices, and achieve higher recording density and wider recording area. In addition, the proposed slider is supported by parallel flat springs to reduce tilt motions of the slider in the pitch and roll directions. In this paper, the static and dynamic characteristics of the proposed slider are investigated theoretically and experimentally. It was consequently found that the proposed slider could follow a wavy disk surface with 100 μm amplitude with tracking error of 300 μm_p-v in the vertical direction and tilt angles of less than 5 minutes_p-v in the pitch and the roll directions.

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Recently, electricity and an electronic equipment which centers on portable terminals such as cellular phones and notebook computers have been rapidly widespread. The through hole processing by micro diameter drill to connect the conductor layer of the printed wiring board is an especially important process for forming the circuit. After the drilling, plating is done on each through hole wall to connect conductor layers. The plating thickness becomes not uniform due to the through hole wall roughness, and so there is a possibility of disconnection of plating by thermal shock. Therefore, to improve the reliability of an electric connection, the improvement of the through hole wall quality is desired. However, it has been considered that a lot of factors influence on the quality of the through hole wall. Then, the purpose of this report is to apply data mining that is the method of statistically analyzing the factor to the image processing data, and to elucidata the factors which influence on the deterioration in the through hole wall roughness. In addition, we take the Motif method developed by Keogh in order to express through hole wall quality more accurately. Following conclusions were obtained : (1) The cutting distance, drill temperature, and width of the fiber bundle of yean influence on the deterioration in the thorough hole wall roughness. (2) Number of “rough” Motif and the size of Motif influence on the stability of thickness of plating.

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The purpose of this research work is to produce micro part reinforced by unidirectional short fibers by laser photolithography. Ferromagnetic short fibers are added to liquid photopolymer. By applying magnetic field to this mixture, the axes of the short fibers are aligned along the direction of the magnetic field. Then, the photopolymer is solidified by the irradiation of UV laser in the desired shape. The apparatus for applying the magnetic field is composed of four electromagnets in horizontal directions and one in vertical direction. The magnitude and direction of the magnetic field generated by these electromagnets can be changed. The degree of the alignment of the short fibers is examined using this apparatus. Several examples of micro structure reinforced by unidirectional short fibers are produced by this method.

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