In this paper, we discuss COG-correspondent Optimal Body Postures (COBP) of a quadruped robot corresponded with optimal height of the center of gravity (COG) while performing ommidirectional walking on a slope. The COBP is the posture where the moving velocity is maximized corresponding to the height of COG, with respect to the slope and moving direction.The proposed method based on dynamically changing height of COG and body posture during gait-transitions, is used to maintain high robot motion velocity and stability on slope. Through computer simulation, the validity of the proposed method has been demonstrated. The stability has also been confirmed in computer simulation in gait-transition by means of static stability margin.

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Among high-speed railway systems, the superconducting maglev train is an innovative transportation system, in which trains are levitated and driven at speeds of up to 550 km/h. But is case of quench of superconducting magnet, vehicles are forced to touch down on the guideway. For safe landing, we developed the new equipment named “Guide Stopper”. Our process of development is as follows : (i) To know the maximum load for the landing, we simulated the electromagnetic power and dynamics of vehicles. (ii) Each element of guide stopper was developed and tested in a factory. (iii) Quench tests were conducted on the Yamanashi Maglev Test Line and results showed a good accordance between simulation and test. Through the study and development of guide stopper, we established a design method of safety equipment for Maglev.

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In order to detect a transverse crack due to fatigue, most of the researches have so far paid attention to resonances of steady-state oscillations due to a crack and proposed diagnosis systems utilizing those vibration phenomena. However, in a practical view point, these diagnosis systems have the following defects : (1) The probability that a resonance due to a crack occurs in the rated speed range is small. (2) It is very dangerous to observe vibration characteristics in resonance ranges spending long time. In this paper, we propose a new method utilizing the changes of vibration phenomena due to a crack in a nonstationary oscillation during start up of a rotating machinery. The advantage of this method is that we can check the signals denoting the occurrence of a crack in a wide speed range by a single sweep and also can avoid the operation in dangerous resonance ranges. Moreover, the validity of the proposed method is shown through numerical simulations and experiments.

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This paper describes vibration analysis using finite element method for elastic blocks connected by a nonlinear concentrated spring. The restoring force of the spring is assumed to be expressed by power series of the relative displacement between ends of the spring. Finite element for the nonlinear spring is expressed and is connected to the elastic blocks modeled by linear solid finite elements. Further, the discretized equations in physical coordinate are transformed into the nonlinear ordinary coupled equations using normal coordinate corresponding to linear natural modes. This transformation yields computation efficiency. Influences of Young's modulus on nonlinear frequency responses for the elastic block are clarified.

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This paper deals with optimal design strategy of the connected control method for flexible structures with same dynamic properties. One of the authors had already proposed effectiveness of connected control method for vibration control of flexible structures arranged in parallel. However, its control performance reduces as the natural frequencies of structures become closer. Therefore, the authors have presented a modified control mechanism in which the actuators are connected to the structures with a difference in its connecting position using long arms. However, its optimal design strategy of vibration control device has not been established yet. In this report, the optimal design strategy of passive control is derived. Computer simulations and experiments are carried out and the effectiveness of the presented optimal design strategy is confirmed.

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This paper proposes a new design method of semi-active optimal control system. This method uses the nonlinear predictive control theory proposed by Horiuchi to design a controller and considers nonlinear characteristic of damper or spring that possess variable parameters. This controller predicts the nonlinear response of continuous system one-step ahead by using the state equation. Control inputs are determined by minimization of predictive tracking errors and control inputs. Moreover, this paper proposes a novel MR damper with an expanded variable damping region using both electric and parmanent magnelts. Damping coeffecient of the damper is made increased by adding positive current and decreased by negative current. Proposed approach is applied to vibration control of multi buildings connected with the MR damper. Effectiveness of the presented controller and MR damper is examined through simulation and experiment under random and earthquake wave excitation.

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The authors have proposed an analytical model by which they can simulate the experimental results of a piping system with full circumferential 50% thinning at an elbow or two elbows. A series of elasto-plastic analyses has been carried out in order to investigate the experimental behavior of the piping system. Dynamic analyses describe the ratcheting behavior and the average amplitude of the opening-closing displacement at elbows relatively well. And then static analyses describe ratcheting and ovaling of the cross section of pipes fairy well.

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We developed a new method for accurate estimation of the excitation force of an electric motor by inverse system using measured acceleration response. To solve this inverse problem, we employed an accelerometer to measure the accelerations of the supporting beams of the motor. In the experiment, the acceleration of a beam was measured when the motor was in operation. Additionally, the inverse system was created by using the equations of motion for both the motor and the supporting beams. The results obtained by this method agreed well with the results of the excitation force measured by using a load cell directly.

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This paper reports damage detection and vibration control of a new smart board designed by mounting piezoelectric fibers with metal cores on the surface of a CFRP composite. Damage to the board is identified on the assumption that the piezoelectric fibers used as sensors and actuators are broken simultaneously at the damaged location. First, the length of the piezoelectric fibers is measured to derive a finite-element method (FEM) model of the cantilever beam. If the fiber length is shortened due to a break, there is a decrease not only in actuator performance but also in the sensor output. Damage detection is based on the computed relation between the input/output signals and the damage position. Furthermore, a reduced-order model that considers only the first mode is derived for the controller design and transformed into a linear fractional transformation (LFT) representation for the gain-scheduled controller design. The position of the damage is the contributing parameter in the variation. Next, the gain-scheduled controller is designed using LFT representation. Finally, the experimental results of the damage detection and the gain-scheduled control are presented. These results show that our gain-scheduled controller can improve control performance when damage causes a break in the piezoelectric fiber.

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This paper deals with sensor signal noise of eddy current testing (ECT) probe generated in helical heating tube in the fast breeder reactor MONJU. ECT probe is used for inspection of thickness of heating tube. The heating tube is composed of helical tube and straight tube because of advantage of thermal efficiency and compact size. However, the vibration of probe having no experience in usual straight heating tubes is generated. The vibration causes the noise and the decrease of sensor sensitivity of ECT probe. The experiment was performed by using a mock-up, and the noise characteristics of ECT sensor signal mounted in ECT probe were examined. The experimental result showed that the sensor signal noise in inserting ECT probe was higher than that in return process and the vibration in insert process had a certain outstanding frequency. It was effective for the countermeasure of sensor signal noise to attach the long and flexible guide probe to the top of ECT probe.

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A diagnosis of a helical heating tube installed in a fast breeder reactor is operated by an insertion of an eddy current testing (ECT) probe with magnetic sensor into the tube. An undesirable vibration of the ECT probe always happens under a certain condition and makes the diagnosis difficult. The cause of the vibration has not been clear. Numerical simulation of the vibration is implemented on the assumption that the vibration is caused by the Coulomb's friction. An analytical model is derived as a large scale nonlinear vibration system and a lot of computational costs are ordinarily required to carry out the simulations. The Transfer Influence Coefficient Method is applied so that the simulation is efficiently carried out. The results of simulation qualitatively agree well with the experimental results. It confirms the validity of the assumption that the vibration is caused by the Coulomb's friction.

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When an isolation device is exposed to earthquakes, the relative displacement between the device and the ground increases. The purpose of this research is to decrease the relative displacement by using the friction force. An analytical model in consideration of the friction force is proposed, and simulation analysis under the famous earthquake waves is performed. Consequently, as the friction force increases, the results show that the relative displacement decreases. However, it is found that the response acceleration increases. It is thought that optimal friction force exists, and this force decreases both the response acceleration and the relative displacement. This is considered to change with the properties of earthquake waves. It is shown that the relation between the optimal friction force and the maximum input acceleration is approximately linear from the results of many seismic waves. It is thought that the response acceleration and the relative displacement can be decreased changing the friction force to the most suitable value for each earthquake according to this relation. This isolation device is examined with simulation analysis.

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This paper addresses active power flow control of a distributed-parameter planar structure. From the viewpoint of wave propagation, this paper presents a novel power flow control employing vibration intensity as a criterion of vibration energy flow. It enables to generate a quiet zone where structural vibration is completely suppressed in the vibrating structure. Applying cluster feedback control approach, a control method generating a quiet zone on a designated area of the target panel is proposed. Finally, a numerical simulation and an experiment are conducted with a simply supported plate, demonstrating the capability of the active power flow control for generating a quiet zone.

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Active noise control of a moving point has been examined in our previous papers. The feature of the model is that the transfer characteristics between the noise control source and the evaluation point (aimed noise reduction point) change with the movement of the evaluation point. Real time character identification algorithm have been introduced to handle the problem. However, the convergent algorithm used in the identification works effectively only when the system is stationary, and this is one of the reason that the identification accurcy decreases when the speed of the evaluation point increases. Besides, the evaluation point moves during the identification process of the calculation and it can cause discrepancy between identification results and the real system. We propose new technique where transfer characteristics are divided into time delay factor and main components. Once the characters are divided, the change of transfer characteristics caused by the movement appears mostly in time delay factor, and since it is the function of the location, it is easy to get the delay factor. Applying this idea, one can expect remarkable improvement in the identification. This method is examined numerically and experimentally in this paper.

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The fantastic light of firefly, which keeps fascinating the heart of Japanese from ancient time, and the ecosystem are taken up as one of cure fields being benefit from the nature. In this study, from a viewpoint of Kansei engineering, we focused on the hue of light emission pattern of firefly, and we examined whether it causes the human spirit any effects or not by using various statistical analysis and Kansei analysis. It was revealed that there is a high possibility that the sufficient cure effect exists in the hue of light emission pattern of firefly and the ecosystem. This research is the first basic trial turned to the creation of cure spaces for hospice and welfare facility, which utilize the firefly and the mini ecosystem artificially modeled in an enclosure.

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In order to cope with image defects observed in the electrophotography using the single-component magnetic development system, a two dimensional numerical simulation has been carried out considering effects of multiple physics. The electrostatic field generated by the bias voltage applied and the electric charge on the photoreceptor and the toner particles are calculated using the finite difference method. The pressure equation is also solved by the finite difference method to obtain the flow field induced by motion of the photoreceptor and the development sleeve. The magnetic field is expressed by superposition of fields created by two-dimensional magnetic dipoles to extrapolate measured magnetic flux density on the development sleeve. Total force exerted on each toner particle by those fields are calculated and motion is tracked considering adhesion onto solid surfaces to estimate density distribution of toner particles on the photoreceptor. Two types of image defects are simulated. One is low-density area observed near a white line with dark background. The other is a phenomenon that large particles contained in the development particles are intensively developed on a non-image area close to a solid patch. Countermeasure against the image defect is also simulated.

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To achieve high-efficiency biped walking, we have proposed a self-excited biped mechanism and clarified the characteristics of the self-excited walking whose supporting leg's knee is straight and bending by the simulations and experiments. This paper presents walking characteristics of a self-exciting biped mechanism with a cylindrical foot when the stance leg's knee is bending. We examined how the mass and length ratios of shank to leg affect the walking characteristics. We further examined the combination effect of the bent knee angle, attaching angle of the cylindrical feet, upper body mass and its attaching position on the walking performance. As a result, we found that the walking velocity can be increased by decreasing the attaching angle of feet. Although the upper body mass decreases the walking velocity, the walking velocity can increase greatly by shifting the additional mass forward only slightly. We also verified the effect of knee angle and attached mass position by experiment.

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It is important to reduce the vibrations of an Interior Permanent Magnetic motor that is generally installed in electrical vehicles, fuel cell vehicles, and hybrid electrical vehicles. The purpose of the study here is to build up the torque ripple reduction methodology by controlling the working currents on IPM motor. The distributed winding IPM motor with 48 teeth on the stator and 4 pairs of poles on the rotor is treated. The relating equation between torque and three phase alternating currents is shown firstly, utilizing the torque that results from the Finite Element Analysis of the plane electromagnetic field. Secondly, high order currents are derived from the equation and superposed on the basic currents in order to reduce the torque ripple. Finally, the plane electromagnetic field analysis is performed again with the currents including the high order ones and a torque ripple reduction of more than 25 dB with a torque drop of 2.2% is obtained.

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As an alternative to an electromagnetic motor, a traveling-wave-type ultrasonic motor (USM) has been attracted considerable attention. In this paper, torque control system design of the USM is discussed to implement the USM for a robot. The torque control method is proposed to apply the friction contact model as the control model of the USM and vibration amplitude control is built into the inner loop. Actually, torque control is conducted using the designed system. Firstly, the USM is modeled as the 3 models : the vibration model, the friction contact model and the rotor model. The friction contact model is the discrete spring model taking into account the slip. Vibration amplitude control is proposed and designed because the spring model assumed that the vibration amplitude is known. Secondly, the control apparatus using FPGA (Field Programming Gate Allay) is constructed and the control experiments are conducted. Relationship between torque and rotational speed is measured to verify the friction contact model. Finally, torque control experiment is conducted using the designed vibration amplitude control. Experimental results show that the designed torque control has an advantage over previous studies.

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A novel control method for master slave system with communication delay is proposed. This control method consists of an improved unilateral controller and autonomous controllers and suppressors. The improved unilateral controller switches a control method according to a contact state. When the slave is not in contact with an object, the improved unilateral controller is a position controller. When the slave is in contact with an object, the improved unilateral controller is a force controller. And a controller sends a information of contact to the master. Autonomous controllers and suppressors are placed in a master side and a slave side. A slave autonomous controller controls a fingertip force to avoid a slipping. A master autonomous controller predicts and controls a reaction force. A slave suppressor coordinates outputs of a slave autonomic controller and unilateral controller. A master suppressor coordinates a predict contact position and a real contact position. To validate this control method, we constructed a master slave system. And validity of this control method is confirmed by some master slave experiments.

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A simple control valve using a magneto-rheological (MR) fluid was proposed and called the MR valve. The MR valve utilizes the apparent viscosity controllability of the MR fluid in magnetic field and controls high-level fluid power without moving parts. However, conventional MR fluids have high base viscosities to disperse heavy soft iron particles and lose fluid power in pipes. In this study, low base viscosity MR fluid using lightweight ferrite particles was proposed, developed and applied to an MR valve. First, four MR fluids were fabricated with different compositions and the MR fluid to minimize the MR valve was experimentally selected. Second, a small-sized three-port MR valve using a permanent magnet was proposed and the design procedure was theoretically derived. Third, a three-port MR valve was fabricated and the characteristics were experimentally clarified. Also, as an application of the MR valve, a bellows-driven one-link manipulator was fabricated and tested.

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We have developed a novel method of manipulating DNA molecules in liquid by laser. At first, we propose in-situ formation of gel microbead made of the thermoreversible hydrogel. Irradiation of a 1064 nm laser to the aqueous solution mixed with poly- (N-isopropylacrylamide) through a high magnification lens resulted in formation of the gel microbead at the laser focus by heating. Next, we propose to manipulate DNA molecules by the gel microbead, which is trapped and maniqulated by the laser scanning. The technique allows DNA molecules to be manipulated at any point without the need of prior chemical modification of the microbead. We investigated characteristics of gel microbead formation by laser irradiation. We succeeded in manipulation of DNA molecules in high speed.

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Some living beings both on ground and in water can move by forming traveling waves along their bodies, therefore the mechanisms using the traveling waves have the amphibious possibility. Several robots have been developed using the mechanisms, but there are no amphibious robots. In this study, our goal is development of a bio-mimetic soft cord robot which can move on ground and in water. First, we took particular note of a millipede and an eel, because they are similar to point of using the traveling waves for moving, but their living environments are different; the millipede lives on the ground and the eel lives in water, and their moving principles were cleared theoretically and confirmed by computer simulation. As the result, the relations between their moving and the progressing directions of traveling waves were made clear. Second, a soft cord robot, 915 mm in length, 11 mm in width and 5 mm in height, which was based on the principles of the millipede and the eel was developed. Finally, the experiments of the robot were carried out, and they showed that the robot could move both on the ground and in water successfully. Moreover the robot could negotiate in the curve tube without special control algorithm because of its high compliance.

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This paper analyzes grasp stability of two objects in two dimensions. In the previous researches on the grasp stability, the number of grasped objects is restricted to one. For efficiency of tasks, multiple objects had better been grasped and manipulated by a robot hand. In order to design stable grasp, grasp stability of multiple objects must be quantitatively evaluated. In case of two grasped objects in two dimensions, the number of parameters of object displacement is six. However, the displacement of the objects is constrained by each other, because the contact between the objects must be maintained. Independent parameters of the object displacement are provided and then finger displacement is derived. The grasp stability is evaluated from the viewpoint of the potential energy method. From numerical examples, the effect of curvature at contact point between two objects is demonstrated. The effect of this curvature stands for the feature of multiple objects.

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We propose a new method to estimate joint torque of human arms in underwater environment. In the proposed method, a parallel wire driven system drives an end point of a subject's arm to measure the end-point force, and joint torque is estimated with the measured end-point force and the subject's limb length. Since the force sensors with wire used in this system is small enough, the measured torque can be gained under less influence of hydrodynamics on the sensors. We verify the accuracy of the estimation method experimentally and confirm that the proposed method can estimate joint torque of a human arm. We compare the joint torque data of the same trajectory in the different environment and extract the effect of hydrodynamics on human motions in underwater environment.

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In the first report of this subject, a linear MR (Magneto-rheological) brake specially designed for prosthetic ankle joint to keep dorsal flexion in swing phase of gait has been presented. The brake using MR fluid has simple structure and can control its brake force with low voltage. MR brake is expected to improve the function of lower extremity orthosis for rehabilitation. In this report, we improved the developed MR brake, and made a prototype of intelligent prosthetic ankle joint. Walking experiments were carried out and the control performance of the developed intelligent prosthetic ankle joint was confirmed.

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Detecting obstacles on road surfaces is important technology for visual navigation of automomous vehicle. So we propose the method of detecting obstacles using perspective projection with Homography matrix. By using Homography matrix, it is possible to detect obstacles on horizontally planer road only. But road is not always flat. Therefore, we expand the method for detecting obstacle on the pitching road. Analizing projection error, we divide pitching road into multi-planer and project with Homography matrix onto each area.

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This paper is concerned with the development of an in-situ measuring device for evaluating the swelling/desweling characteristic of temperature responsive polymer gels by the piezoelectric admittance measuring technique. The device is a simple cantilever type transducer, which consists of an aluminum cantilever beam, a piezoceramic patch and a probe coated with the polymer gel. The probe can be easily assembled to the cantilever transducer with a double-stick tape. In this paper, the characteristic of the transducer is investigated first with the aid of FEM analysis method. Based on the simulation results, a prototype piezo-transducer and probe coated by polymer gels are made. The characteristic of the gel is tested in situ experimentally. The results validated that the water content in the gel can be detected simply by the transducer. Furthermore, two kinds of membrane coating methods were investigated. The results obtained by the proposed transducer indicate that the directly coated gel membrane has higher temperature response in the water content than the pasted gel membrane.

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This paper describes a control method for a power assist device used in factories. An adaptive control scheme is employed to control the power assist device and to estimate its dynamic parameters. Using the adaptive control, the maneuverability of the system is good in free space but it is very dangerous in the task of which an object supported by system contacts on a floor or a wall. Therefore, we propose an improved system controlled by an adaptive control in which the local control method changes to a feedback or a feedforward control in the contact condition. The improved system detects collisions based on the difference between the actual input torque to the power assist device and reference input torque, which is calculated based on the estimated parameters of the manipulator dynamics. Then, the effectiveness of the system is shown.

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The following has been understood for the change in the steer characteristic and the amount of perspiration in the drift cornering when not only visual information but also body sensory information is added. When body sensory information joins visual information as for the driver, it has been uuderstood that the amount of perspiration increases overall and can do the drift control continuing with a moderate tension. In the drive only of visual information, the driver comes to arrive easily at spin because the drift control is difficult. And, it has been understood that the amount of perspiration increases greatly compared with the case to give body sensory information, and becomes the one with a very high risk. Moreover, the driver can control an adequate drift compared with driving only visual information in feed back body sensory information on the roll angle to the steer. Therefore, the importance of the perception of the state of the vehicle by giving the driver moderate body sensory information was able to be confirmed, and a preferable direction as the vehicle was clarified.

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To provide good vehicle control in critical cornering, it is important to be able to sense the point of critical cornering. Even if the point of critical cornering is exceeded, it is possible to control the vehicle when drift control is good. As such, a compromise exists between the sensing of critical cornering and drift control. Experiments using a driving simulator were performed on different subjects to investigate this trade-off. It was found that the driver was able to sense the point of critical cornering easily from the change in body slip angle, and to control drift easily with a large body slip angle, in which the tire can attain a high cornering force. When the roll rigidity was low, however, drift control deteriorated although the sensing of critical cornering improved. Therefore, a moderate level of roll rigidity or roll rigidity control is desired to achieve a balance between these two factors.

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The present paper discusses the driving/breaking force distribution for direct yaw-moment control (DYC) of the independent steering vehicle. The objective function is the maximum value of the tire workloads. In the case of conventional four wheel steering vehicle, the algebraic expressions of the optimum driving/breaking force distribution have been derived by the authors. Based on the previous results, the optimization algorithms for the independent steering vehicle are newly developed. For the front independent steering vehicle, the binary search is employed, and this online algorithm is combined with the golden section search method for the independent four-wheel steering vehicle. The convergences are guaranteed by the convexities of these optimization problems. Numerical simulations with CarSim, a popular multi-degree-of-freedom vehicle model, are performed to prove effectiveness of the proposed control schemes.

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I conducted an experiment for analyzing effecs of various kinds of talking modes, especially on a mobile phone on driver's performance. Five different talking modes were set up : hand-held phone, hands free system using earphone, hands free system using loudspeaker, ordinary face to face conversation and no-talking. The author focused on mental workload and situation awareness of surroundings in driving and also focused on the difference concerning these two factors in each talking mode. The study concerning mental workload and situation awareness reveals that no significant difference was found between face to face conversation and hands free system using loudspeaker, while significant difference was found between face to face conversation and using earphone.

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A new golf swing robot to simulate human motion has been developed by authors. This paper deals with motion control for the robot hitting a ball. In the case of golf swing, it is difficult to control the impact process itself, because the time of impact between the club head and the ball is extremely short. Therefore, it becomes important to control the robot after the impact, to avoid breaking a club, etc. In this paper, a method for controlling the robot adaptable to various impact conditions, is proposed. The motion state of the robot is estimated first by an extended Kalman filter, and a new reference trajectory is generated on-line according to the estimated state. The method has been implemented to the robot, and its effectiveness is shown by experimental results.

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Gripping force during golf swing has close relationship with the performance and the feeling of the club. Friction on the grip surface must be an important factor as well as the normal force. In order to elucidate the gripping force on both pressure and friction, a sensor chip was developed that detects the force in radial direction (Fz), tangential direction (Fx), and axial direction (Fy). Using a sensor grip equipped with four sensor chips, gripping force on finger and palm in swing action was measured. The forces change at five periods on swing start, downswing start, wrist release, impact and after impact. In downswing, the axial friction is larger than the tangential one on the left hand. On the other hand, the tangential friction is larger than the axial one on the right hand. This indicates that the left hand makes the centripetal force to rotate the club and the right hand controls the head surface direction around the shaft axis.

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Priority rules for dynamic job shop scheduling are desired to have high performance and comprehensibility as far as possible. This paper presents a priority rule development method to make those priority rules. Two different types of neural networks are used for this purpose. The first type of neural network, which is a universal approximator, is used to learn a priority rule having high performance as far as possible. This neural network is trained by iterative dynamic scheduling simulations. After training this neural network, the input-output pairs of it are collected by applying it to dynamic scheduling simulations. The second type of neural network is used to extract simplified rules from the input-output pairs. This neural network corresponds to a priority rule expressed by a monomial and is trained by a back-propagation algorithm with forgetting to simplify the extracted rules. Numerical experiments show that the priority rules developed by the proposed method are comprehensible to a certain extent and have better performance than the best priority rules in the literature.

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We have proposed a dynamic scheduling method using the mixture of a genetic algorithm and a priority rule. In the method, a dynamic scheduling problem is assumed to be a series of static problems and scheduled on a rolling basis. In this paper, we examine the effect of priority rule used in the method. For this purpose, two types of the ATC rules having two parameters are used. The first type is the rule whose parameters are tuned for the dynamic scheduling environment. The second type is the rule whose parameters are tuned for the imminent static scheduling problem. Numerical experiments show the followings : The proposed scheduling method searches effective schedules guided by the priority rule and the rule has important effect to the scheduling performance. For the dynamic job shop scheduling, the scheduling method using the first type of ATC rule greatly outperforms the one using the second type of ATC rule. The reason can be explained by considering the due-date allowance contained in the optimized schedules.

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An automatic page turning machine is in demand to use for the highly informationalized society or a highly welfare society near future. The key technology for the page turning machine is sensing a page-turning over. In this research, the authors noticed the tactile sense of finger, and then, roller which detect the vibration by the PZT were designed. This type of roller was named as a Tactile Sensor-Integrated Roller. Two types of roller, which is different in the suppporting way of the PZT, were producted. The roller type I can sense the slipping/feeding between roller and paper by the wave form, and the roller type II can discriminate the slipping/feeding/turning-over by the output amplitude. A page turning machine was also developed and evaluated its performance using roller type II. When the threshold voltage is set at 0.8V, 93% of rates of distinction of turning over is obtained. This method can be used for a book of different quality paper, though the treshold voltage should be adjusted.

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The purpose of this study is to design and evaluate an automatically page turning machine and roller system which is applicabe to various books. The key point of the page turning is how the roller can sense turn of a page and it can turn only one page surely. In this paper, the Roller with Relative Rotation Sensor system which consists of two driving rollers and one sensing roller in the same axis is proposed. By sensing the difference of rotation between the driving rollers and sensing roller, it leads to detect the turn of a page. Furthermore, failures of page turning such as consecutive turn, duplex turn, kink of page and drop of page are observed. For the jugdement of turning motion, it is clarified that the sensing roller with diameter of 28.3 mm and rubber hardness of A40/S is good at the performancee; it records 100% at a magazine made of high quality paper (0.07mm), 92% at an old book made of high quality paper (0.07mm) and 93% at a magazine made of coated paper (0.11mm).

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The accurate measurement of strain and stress in a tooth is important for the reliable evaluation of strength or life of gears. In this research, the strain measurement method which is based on an image processing is applied to the analysis of strain near the tooth fillet. The displacement of the point in the tooth flank is tracked, and then, the strain is calculated. The interrogation window size of cross-correlation method affects the accuracy and the resolution. In case of the measurement at the complicated profile such as fillet, the interrogation window keeps big size and the overlap amount should be large. The surface condition also affects the accuracy. The white painted surface with small black particle is suitable for measurment.

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Recently, in response to needs for smaller size and higher recording density of electronic components, there has arisen a demand for a technology that draws liquid material directly on substrate in high accuracy. In many cases, minute fine particles are included in the high viscosity fluid material. And the diameters of particles are from several micro meters to tens of micro meter. However, there was no method of controlling high viscosity and a powdered fluid without mechanical contact. In this report, we propose “Non-contact flow control valve” that satisfied following (1) (2). (1) The discharge passage is completely opened or completely shut off by changing the gap, and the gap of valve can keep 10 micro meter or more at any time. (2) It is possible to shift quickly by the order for milli-seconds among the ON/OFF state of fluid discharge without big flow change. (1) was achieved by “Spiral grooved thrust dynamic seal method” to control axially with two degrees of freedom actuator which is composed of a giant-magnetostrictive alloy and a DC servo motor. (2) was achieved by “Double piston method” that used the squeeze pressure effect. In this report, the experiments of drawing line using the developed dispenser equipped with above mentioned (1) (2) were done. As a result, starting and ending edges of the line were able to be formed with very high quality without lack of line, clod of fluid, dripping and thread-forming.

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This paper presents a study on acoustic emission (AE) in the bending fatigue process of super-carburized spur gear teeth. Research was carried out on AE signals, AE cumulative event count, AE event count rate, AE cumulative energy count, frequency spectra of AE signals and crack length in the bending fatigue process of eutectoid-carburized SCM415 steel, super-carburized SCM415 steel and MAC14 steel gear teeth. The relation between the AE parameters and the bending fatigue crack propagation as well as the effects of gear materials on the AE characteristics in the fatigue damaging process of the gear tooth were determined. Wavelet transforms (WT) of AE signals of these gear teeth were carried out, and then WT maps of AE signals were examined, Basic data were obtained for the prediction and diagnosis of bending fatigue failure of the supper-carburized gear tooth by means of AE method.

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CVJ lines of front drive automobiles are composed of the tripod constant velocity joint (CVJ) or the double offset CVJ, the Rzeppa CVJ and the drive shaft. The rotational angle error of the CVJ line and the whirling motion of the drive shaft (the tripod shaft) and its fluctuation of axial direction are analyzed experimentally. From the results of experiments with several values of the angle α between the housing shaft of the tripod CVJ and the drive shaft and the angle β between the outer-race shaft of the Rzeppa CVJ and the drive shaft, characteristics of the rotational angle error and the three dimensional motion (the whirling motion and the fluctuation of axial direction) are clarified.The rotational angle error is sinusoidal of 2π/6 period. The whirling motion has the period of 2π or 2π/6 according to the angle β.

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In this paper, we discuss an experimental and theoretical investigation of the basic performance on the transmission efficiency of 3K type CVT with a ring and cones. The analysis was carried out using a formula on efficiency of the planetary gear and a theoretical formula on the contact area which is based on elasto-plasticity model of traction fluid. The transmission efficiency was calculated by the experimental results obtained from the rotations and the torques on the input shaft and the output shaft. As a result, we found the theoretical result corresponded to the experimental result on the transmission efficiency of CVT. Moreover, the efficiency decreased due to the influence of the bearing loss, when the load torque decreased. The speed ratio, which is calculated by considering the slip on the contact area, was showing a tendency to decrease with the increase of the load torque. It was also confirmed that an analysis method was valid with the calculation of the power transmission efficiency of 3K type CVT.

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The purpose of this paper is to clarify the shoe dimensions required to improve the lubrication characteristics on sliding surfaces between shoe and swash plate in a compressor. The steady incompressible flow between shoe and swash plate was numerically simulated by finite volume method and Newton-Raphson method. The calculation results were compared with experimental ones measured by optical interferometry. The oil film thicknesses were successfully predicted with boundary condition imposed mass imbalance for the volume called dimple in sliding surface. It was found that the pressure in dimple consorted with the load acting on the shoe, and that optimizing the outer profile height and profile peak radius, increasing the sliding surface radius and decreasing the dimple radius effectively increased minimum oil film thickness.

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The cross sectional area of threaded fastener has a complicated configuration due to the helix that characterizes its essential function of tightening structural members. When estimating the strength of threaded fasteners under external loads, the use of “stress area” is recommended in JIS B 0251. It is desired, however, to establish a procedure to calculate the true cross sectional area of screw thread by taking account of the effects of root radius in order to elucidate the various mechanical behaviors of bolted joints. In this paper, an analytical expression is presented to calculate the true cross sectional area with simple algebraic equations. Then, its “equivalent diameter” is defined and compared to effective diameter corresponding to the stress area defined in JIS B 0251.

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This paper considers an assembly scheduling problem for a flexible manufacturing cell (FMC), which consists of m dedicated machines and an assembly machine. There are n jobs to be processed in the FMC. Each of the dedicated machines produces a component of a job. In addition to m components, each job requires some other components purchased from outside. The assembly machine cannot start processing a job until both of all the m components produced in-house and components purchased from outside are available. The objective is to find a schedule of the n jobs that minimizes the makespan. It has been known that the scheduling problem is strogly NP-hard even when m=2. This paper proposes a branch-and-bound algorithm to the problem. The exact algorithm is examined by means of numerical experiments with up to 400 jobs, and the results are reported.

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There are various methods of joining metal and resin in manufacturing. Conventional joining methods have of course many advantageousnesses, but new methods suitable for recycling metal and resin have been expected. In this study, a method of joining the two materials using shearing technique was investigated. This method allows metal and resin to be joined without the need to use a third material, therefore enabling the metal and resin to be withdrawn independently and recycled. This method uses a pair of punch and die. It can be applied to aluminum, polypropylene, and hard polyvinyl chloride. It consists of the following steps first punching a hole in the metal sheet by punching, then pushing the sheared holes on the metal with resin, and finally the finishing process. The joining force is measured by tensile tests. Joining was found to be influenced by type of resin used, punch travel, and clearance between the punching and pushing process from the strength evaluation. The joining force can be controlled to vary these factors. From a simple analysis, it is known that the joining strength is generated by shrinking an outer pierced hole over inner resin cylinder.

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Recently, magnesium alloys are often applied in the auto industries and electric appliances. Most of them are manufactured by using some casting method. However, from the viewpoints of productivity and quality of product, it is easily expected that the develeopment of press forming technology is strongly required along with other metals and alloys. In this study, first, warm deep drawing tests were performed to understand its deep drawability. From the result of drawing test, limit of drawing ratio of AZ31B plate is resulted in 3.0 by heating the die and cooling the punch. Next, simulation of warm deep drawing on AZ31B magnesium was tried and evaluated for calculating the optimum press condtions. FEM with non linear and dynamic expricit was used for the simulation. In the simulation, the tensile tests were performed to understand its material behavior, and forming limit diagram (FLD) was also used to decide the drawing limit. It is concluded from the results that (1) The simulation of warm deep drawing on AZ31B magnesium conformed to the resluts of the actual experiments. (2) The simulation was very effective for calculating the optimum press condtions.

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In order to make a product light, the use of aluminum as a material instead of iron is increasing. It is considered that this tendency will continue from now on. However, aluminum has the faults that the hardness is low and that the surface is easily damaged in comparison with iron-based materials. In this study surface modified layer was formed on the surface of aluminum alloy A5083 by irradiating a YAG laser beam with the wire made from stainless steel supplied. Surface was modified under various conditions in order to obtain high hardness having no crack. As a result, we got the thick modified layer with high hardness on the aluminum alloy. The hardness distribution in the inside of the modified layer was almost uniform.

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