The module structured production systems that aim for the demand synchronized production has a function and composition for high-variety low-volume production. However, an efficient dispatchig to production lines is a problem to be solved. Two requirements are necessary for the dispatching order system to solve this problem. The first requirement is that production order must be decided with parameters of evaluation values that affect efficiency. For quick response to actual orders and variable conditions of manufacturing lines, deciding a production order with short processing time would be essential. And the second requirement is to decide a production order in short time by grasping condition changes of actual orders and variable conditions of manufacturing lines in real time. In this paper, we propose a configuration and operation systems that efficiently dispatch orders by grasping actual conditions of manufacturing lines in real time for meeting customers' various demands. Effectiveness of the system is verified with examples.

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In a recent vibration analysis using CAE, the detailed finite element model which has large number of DOF came to be used. By using the detailed model, the number of mode in unit interval of frequency increase, and the large amount of computational cost and time is required to establish effective countermeasures. In this paper, the new analytical method is proposed to raise the efficiency of analysis by classifying the eigenmodes in the frequency range of high mode density into several groups. Almost all of global structures are consist of many substructures, and the eigenmodes of global structure is composed of combination of eigenmodes of these substructures. In this case, it is important for an analyst to understand the relationship between vibration characteristic of global structure and substructures. Therefore, in the proposed method, the types of each group are defined by the similarity of the mutual relationship between the global modes and substructure modes. The proposedmethod is verified to a finite element model that is a simplified automobile body in white. In this validation, 22 modes are set as the target modes. As a result, these modes are classified into 7 groups by proposed method and the validity of classification result was confirmed.

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An approximate analytical method is developed for calculating the probability density of the response of a Duffing oscillator subjected to narrow band random excitation when the stochastic jump phenomenon occurs. The stochastic jump phenomenon is characterized by the existence of multiple states of amplitude and sudden jumps between the states in the sample function of response. In this paper, the trigger for the stochastic jump is considered, and the probabilities of large and small amplitude states of the response are evaluated. The local probability density function of each state is separately assumed using the equivalent linearization method, and the probability density function of the overall response is derived by sum of these local probability density functions weighted with the probability of each state. In the illustrative example, the calculated probability density functions are compared with the Monte Carlo simulation results. It is shown that the present method well expresses the significant characteristic of the stochastic jump phenomenon.

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Statistics of stochastic jump phenomena in the random responses of a Duffing oscillator subjected to narrow band random excitation are investigated. The deterministic jump phenomena of the Duffing oscillator which is subjected to harmonic excitation correspond to the existence of two stationary responses in some frequency range. These responses differ in the phase angle between the excitation and the response, as well as the amplitude. In the case of the stochastic excitation, there are two states of the response, and the jump between two states occurs suddenly and multiple times in the long sample function. These two states correspond to two stationary responses to the harmonic excitation. In the time histories, two states of the response are quite different when the stochastic excitation is narrow band, but the difference becomes obscurer when the band width of the excitation becomes broader. In our previous research, the product of each wavelet transforms of the excitation and the response is proposed as the frequency decomposed phase angle. It was shown that the product successfully identified the states of the responses in the stochastic jump phenomena. In this paper, the rate of the stochastic jump, the ratio and the duration of each state are chosen as the representative statistics of the stochastic jump, and the relation between these statistics and parameters of the narrow band random excitation is studied.

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The three dimensional characteristics of multi-surface liquid motion in a rectangular tank are investigated. The rectangular tank is divided into two parts by a baffle, which is vertical to the bottom of the tank and does not reach the bottom. The modified Helmholtz equation is derived from Laplace equation by separation of variables, and solved by boundary element method. A good agreement was found between the theoretical and experimental results. Effects caused by the position of the baffle, and the distance between the baffle and the bottom, upon the natural frequencies and corresponding mode shapes are discussed.

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The stabilities of the rigid models equipped with three different types of the lengths of throttle element in the inlet of leakage passage were examined experimentally and theoretically because the mechanism of the instability occurrence due to cavitating leakage flow was clarified. The experimental results of the damping ratio of the models could be explained the trend in the stability of the system in cavitating flow. The analytical equations would be valid as the calculated results of the damping ratio were in agreement with experimental results. Like the system in cavitating, flow, the self-excited vibrations occurred in the model, when the throttle element was located in near the center of the passage.

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The importance of the in-flow oscillation of a single cylinder in cross-flow has been highlighted since an accident in a FBR-type reactor. In-flow oscillations have also been observed in tube arrays. This report is an experimental study on this phenomenon using maximum nine cylinders in a water tunnel. Six cases, one single cylinder, two & three cylinders in parallel & in tandem, and a nine cylinder bundle, are examined. Every cylinder can move only in in-flow direction. The motion of cylinders is measured by the strain gages and by a high-speed digital video camera. The results are compared with the visualized vortex motion. As the results, two exciting mechanisms, symmetric shedding vortex and alternative shedding vortex, are observed, and there is a transition range between these two mechanisms where a large vibration is observed. Then, an additional test has been done to estimate the root cause of the large vibration in the transition range.

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A repulsive magnetic bearing can support a rotating shaft without contact by utilizing a repulsive force between magnets. However, because of the nonlinear characteristic of repulsive force, the vibration during passage through the critical speed may increase. This paper investigates a vibration suppression of the rotating shaft supported by the repulsive magnetic bearing. A vibration suppression method by controlling the axial displacement of the repulsive magnetic bearing is proposed. Its axial displacement control generates the changes of both coefficients of linear and nonlinear stiffness. The parameter optimization for the axial displacement control is performed. These results are validated experimentally.

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In this study, the new type of damper which has the displacement amplification mechanism has been developed ("Pre-Tension-Type-Damper"). This paper describes the results obtained from dynamic loading test and traffic-induced vibration test using the building model (size: 1.4m×0.9m×2.35m, mass: 764kg) which was designed to have the same first natural frequency as the detached houses. Dynamic loading test showed that the restoring force of damper was proportional to the second power of amplification factor by the amplification mechanism, and it can be simulated by the fractional derivative 3-element model over the following range; frequency: 0.01 to 5Hz, internal temperature of viscoelastic material: 10 to 40℃, strain: 0 to 300%. Traffic-induced vibration test showed that the damper reduced the response ratio of structure's acceleration into about 3/4 in the maximum compared with the response ratio of structure without damper, and it reduced the response ratio of relative displacement into about 1/5 in the maximum.

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A high speed intermittent drive, which operates at the resonance frequency of a vibration transportation machine by velocity feedback control, was developed. The intermittent drive enables high speed fixed-quantity supply of works. A conventional intermittent drive of a vibration transportation machine is used in processes such as stuffing a bag with snacks or supplements. Driving vibration transportation machine with small damping at the resonance frequency is efficient, because a big vibration is generated even by a small excitation force. However, driving at resonance frequency is difficult, because vibration characteristics are greatly affected by natural frequency change and disturbance near the resonance frequency. On the other hand, velocity feedback control increases the damping of a vibration transportation machine and suppresses the influence of natural frequency change and disturbance. In addition, it can drive and stop vibration quickly by means of large damping and enables high speed intermittent drive. The high speed intermittent drive realizes high speed fixed-quantity supply, in which the supply amount is in proportion to both amplitude and driving time of a vibration transportation machine, and reduces supply error to less than 5%.

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When elevators travel at high speed, horizontal vibrations of the car tend to be set up by guide rail deformations, so the ride quality deteriorates. Therefore, several active suspension systems have been developed to reduce these vibrations. These systems have six actuators that independently activate guide rollers. To reduce costs and installation tasks, it is necessary to develop a system with a minimum number of actuators and a simplified controller. We have developed a new system that has only three actuators. The controller incorporates an H-infinity control design method in order to consider the stability of the system during any change in load. Furthermore, from a practically view point, it is important to reduce the order of the controller so that on-site parameter tuning time can be reduced. We reduced the H-infinity controller to a P controller. We demonstrated that the maximum amplitude of vibrations of a car with control can be reduced to almost half the amplitude of a car without control.

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In the first paper, the forced vibration with collision in an asymmetric piecewise-linear system excited by general periodic force functions was analyzed applying Fourier series method and an exact solution of resulting vibration was proposed. Next, some resonance curves for harmonic, superharmonic and subharmonic vibration were constructed by numerical calculation. This paper deals with Fourier series solutions of the forced vibration for harmonic, superharmonic and subharmonic vibrations in piecewise-linear system analyzed by the first paper and gives stability criterion analysis for their resulting vibrations utilizing variational equation. Following this theoretical analysis, the numerical calculations are performed and the resonance curves are constructed using the resulting vibrations. In the next place, the stability charts for resulting vibrations are also constructed by numerical calculation. The stability criterions for periodic solutions on steady vibration are discussed utilizing their charts. By using them, the stable branches for the resonance curves are distinguished with the unstable ones.

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The research was carried out on the method for detecting a prior condition that there is no thread on the bobbin. When the thread on the bobbin decreases, it was found that the specific rest pattern of the thread appears. And, it was proven that the reflectivity greatly differed in the thread and the bobbin by the experiment. Using these two experimental facts, the equipment of the noncontact type which outputs the stop signal with sewing machine stopping was developed, when the thread of the sewing machine becomes little. Developed equipment was installed in the sewing machine, and its tests were carried out. When the specific pattern of the remained thread appears and the thread width becomes 3mm, the stop signal has been rightly output from developed equipment. From this fact, it was confirmed that developed noncontact type equipment for measuring the remained thread normally operated, and it was clarified that proposing measurement principle was effective.

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This paper presents the development of a finger-mounted tactile sensor for surface irregularity detection. The sensor is composed of a thin rubber sheet and a silicone rubber with the void in the center. On the center of the rubber sheet, two strain gauges are attached point-symmetrically. In addition, a silicone oil sheet is attached on the bottom of the sensor as a viscous fluid medium for keeping steady contact with the object surface. For mounting the sensor on the finger, the sensor is embedded in a cotton work glove. The user puts his/her finger on the silicone rubber of the sensor and slides the sensor over the object surface. By obtaining difference between the two strain gauges, the sensor responds to the surface irregularity, not to the uniform surface. Furthermore, real-time signal processing utilizing the wavelet transform is introduced for detecting surface irregularity from sensor output signals. Theoretical analysis of sensor output signals and experiments using the developed sensor on the plane surface and curved surface with a small protrusion are presented. The results show the validity of the proposed tactile sensor.

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In this paper, we propose a new topology optimization method to be applied for designing layouts of poroelastic material in an acoustic cavity in order to depress sound pressure levels arising from acoustic resonance. In this method, mean sound pressure levels are minimized utilizing the attenuation of sound by poroelastic material such as sound absorbing material. Biot's theory is incorporated into the optimization scheme to deal with poroelastic material. Air medium contained in the design domain is approximately represented in the expression of Biot's theory. These unified expressions of poroelastic material and air medium by Biot's theory allow to utilize a material interpolation scheme in the density approach of topology optimization. We also propose a new material interpolation scheme that can be applied for poroelastic material. In this scheme, we interpolate several physical quantities such as bulk modulus, densities and porosity that are used in the governing equations of Biot's theory. Several one- and two-dimensional numerical examples are presented to demonstrate that the proposed method can provide clear configurations of poroelastic material that reduce mean sound pressure levels within prescribed evaluation domain for specified frequency ranges.

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As tube banks are set in a duct in a boiler and a heat exchanger, the resonance phenomenon or the self sustained tone are generated due to the interference between a vortex shedding and an acoustic characteristics of duct. It is necessary to know the resonance frequency of the duct, namely sound speed, for avoiding any trouble that may arises. In general, it is said that the sound speed decreases in the duct with tube banks and an evaluation formula is given. However this formula is obtained to apply to the perpendicular direction to the flow. We want to know that this formula is able to apply to the flow direction and to various array patterns or not. Then in this paper, applicability limit of this expression is discussed by using FEM analysis and experiments.

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This paper points out that there is another singular point with Coulomb friction when an end effector of a robot manipulator contacts a surface of an object. The characteristics of Coulomb friction singular points are revealed by both of theoretical and numerical approaches. From the results, it is shown that contact forces dramatically increase as the robot closes Coulomb friction singular points. In this paper we also propose a new control method to overcome problems of Coulomb friction singular points. The effectiveness of the proposed method is demonstrated by some simulation results.

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This paper considers the problem of controlling the planar position and the orientation of an underactuated airship with a reduced number of actuators. The airship is a nonholonomic system described by a set of nonlinear equations. A smooth and time-varying coordinate transformation is utilized to reduce the stabilization problem of the airship to that of a linear time-invariant system. A new observer-based output feedback controller without measurement of velocities is obtained for global exponential stabilization of both the position and the orientation of the underactuated airship. The proposed design method is simple and straightforward. Experiments are performed to validate the effectiveness of the proposed controller.

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A motion of an arm robot handing an object out to a human, taking a time delay at the beginning and the position of the object to be grasped into account, is presented in this paper. The motion algorithm of the robot is constructed considering the following points. The first is the cooperation to the human receiver. The second is an introduction of a time delay at the beginning and a function which reduces the time delay gradually. The third is the realization of the desirable relative position between the robot hand and human hand. To confirm the effectiveness of the proposed motion algorithm, the experiments in which an arm robot holds a cylindrical object out to a human and the human receives the object are conducted. The experimental results show that the generated motion trajectories of the human receivers are very smooth and that the motions of the robot are psychologically acceptable to the human receivers.

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In the near future, there will be a significant problem obtaining workers in the fields of welfare and nursing care because of a labor shortage. To solve this problem, many welfare robots, such as an upper extremity motion assistance robot and a meal assistance robot, have been studied. However, many problems remain regarding the practical application of meal assistance robots. Liquid transfer control is a challenge in robot design for meal assistance robots. Patients who have difficulty swallowing or weak sucking ability require a liquid diet, and there is thus a strong need for the development of a meal assist robot that can avoid spilling. The purpose of this paper is to design the trajectory with spilling avoidance when the spoon containing the liquid is transferred by manipulator. In order to avoid spilling of the liquid, a spilling model was evaluated by using a fluid analysis simulator. The effectiveness of the proposed method is shown by simulations and experiments.

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In order to enhance capability of the man-machine interface, we are attempting to investigate the influence of the proprioception on the cutaneous sensation. We performed a series of experiments based on psychophysics, in which we adopted a circle and eight kinds of oval as stimuli. The diameter of circle is 10mm, minor axes of eight kinds of oval are decreased in 3% step from circle, and each major axis is adjusted to make area of each oval be equal to the circle area. Human subjects judged which stimulus presented on right or left panel equals the circle. The experiment is conducted on both of fingertip and thenar parts to compare experimental sensitivity ratio of the thenar to the fingertip with estimated sensitivity ratio based on density of mechanoreceptor. The figure discrimination sensitivity of the thenar was inferior to that of the fingertip according to low density of mechanoreceptor in the thenar. Two-dimensional shape was not recognized by FA II (fast adaptive type II unit) but SA I (slowly adaptive type I unit) because the discrimination precision was not affected by cooling of specimen. Discrimination sensitivity was not different between free and restricted haptic motions. It is implied that the figure discrimination is modified by not only signals from mechanoreceptive units but also motor signal for the haptic motion.

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This study examined how accurately people can discriminate differences in the friction of flooring samples. Flooring samples of either different friction or elasticities were presented by placing two walking boards made of plywood, each surfaced with one of three different flooring samples, in an end-to-end fashion. Ten young adults whose sight was temporarily cut off by eye masks were asked to walk on the path for 108 trials and indicate whether the flooring samples were different or not. Generally, the percentages of correct answers for the pairs of flooring samples with different frictions were low compared with the percentages of correct answers for the pairs of flooring samples with different elasticity. However, the subjects who scuffed their heel on the ground prior to step on to the samples discriminated the differences fairly accurately, even for the materials with different frictions.

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We developed and instrument to aid transfer for aged person with leg fault. The instrument has a very simple structure to turn on a single fulcrum circumference and is able to reduce the load to care. For rational design, we analyze loads with a simple model which is composed for rigid body link model for the instrument and human body, and linear spring model for the elasticity of buttocks and seat cushion. The results of theoretical analysis explained lift up motion of the transfer. The maximum requirement moment was decreased monotonously with the increase in a seat height and decrease in seat stiffness. To safety design, we should minimize the seat height and maximize the seat stiffness. It was possible to reduce the requirement force for lift up under 1/5 of the elder's weight.

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We conducted one experiment for evaluating usability of screwdriver by use of force manipulability and torque manipulability in arm manipulability. As evaluation index, we used maximum torque and subjective easiness of manipulation to compare results of force and torque manipulability. Ten healthy male subjects participated in the experiment. They were asked to turn a screwdriver in the following conditions: two operational heights (shoulder and elbow heights), and four operational directions (0, 45, 90 and 135 degrees) in three operational planes (sagittal, horizontal and frontal planes). The results showed that good operational direction of torque manipulability accorded with that of maximum torque and subjective easiness of manipulation. From this study, it was found that we are capable of applying to use torque manipulability as one of evaluation index for screwdriver operation.

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When the relationship between the dimensions of the crural area and those of the artificial leg socket is poor, it may cause problems, such as pressure sores in the crural area. This study discusses the mechanical characteristics at artificial leg socket interfaces. A computer-aided design (CAD) model of the crural area was constructed from ultrasonic three-dimensional measurements of a crural model, and a personalized CAD model of the crural area was constructed using a free-form deformation technique. Next, a finite element (FE) model of an artificial leg socket constructed using a preliminary design was synthesized as the leg model. Then, the mechanical behavior at the interface between the crural model and artificial leg socket was investigated using finite element method (FEM) analysis. When the socket was adjusted to the leg, the Von Mises stress at the bottom of the socket decreased. This also had the effect of holding the socket stably.

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A prospect system is offered to detect the plant vermin (e.g. larva of lamellicom beetle) living in the soil without digging up the soil by using a C-band microwave sensor (mean frequency: 5GHz). The characteristic of the prospect system is required to detect explicitly the behavior of vermin moving underground in the vicinity of the surface. The prospective characteristic, however, is limited by the magnitude of microwave attenuation (attenuation constant α) traveling in the soil which is depended on water contents of the soil. First of all, relation of microwave attenuation and water contents of the soil is measured for "Akadama" soil and "Kanuma" soil with uniform grain size, which are fundamentally used in gardening. Detectable critical transmission depth of soil for each water contents is confirmed as the result of the experiment. α was detected quantitatively varying the magnitude of vibration amplitude of mini-speaker (frequency: 1Hz, displacement: 0.1mm, 0.2mm, diameter of diaphragm: 25mm) embedded in the water content controlled soil (volume water contents: 0.3g/cm^3). In this case, detectable critical transmission depths of soil were 105mm, 125mm for the displacement amplitude 0.1mm, 0.2mm. The real movement of the larva of lamellicom beetle (head around width: 4mm, body length: 25mm) embedded in the soil was measured using the system. Critical transmission depths of the soil were 200mm and 100mm for the case of α: 0.1Np/cm and α: 0.2Np/cm. It was confirmed that the system is able to detect the vermin, if the moisture content of the soil is small.

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In tissue engineering, it is important to examine the hardness of cultivated tissues for evaluating their vitality. This paper proposes a new index, "Droplet Hardness", defined by the representative plastic deformation in depth of tissue caused by collision with a droplet whose initial diameter and speed are 80μm and 4m/s, respectively. To understand the nature of physical phenomena of single droplet in collision with a tissue, we newly design and develop a dynamic active sensing system composed of a micro ink jet device for spouting out a micro water droplet and a high speed camera for capturing the dynamic behavior of the droplet after the collision. Through both computer simulation and experiments, we show that the Droplet Hardness is an essential parameter capable of nicely expressing a global hardness of tissue.

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A three dimensional passive dynamic walking is studied in this paper. The subject of this study is a simple walking model with circular-arc sole of a foot, and the period of the stable walking is focused. The equations of motion of the model are derived, and the necessary condition for the walking period is obtained based on the linearized equations of motion. In order to verify the stable walking period, numerical simulations and model experiments have been executed. The results show that the stable walking is possible when the walking period is close to the obtained value.

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In order to establish quantitatively a design method for the McKibben type rubber artificial muscle with the optimal characteristics, analysis of operation is performed by means of the three-dimensional finite element method. First, the three-dimensional finite element method model which does not take into consideration friction between plastics fiber codes is proposed as a simple model for acquiring the design manual of the McKibben type rubber artificial muscle, the compatibility, the experimental values, and the usefulness of a model are examined. Moreover various parameter study (crossed axes angle of a fiber code etc.) of the McKibben type rubber artificial muscle is carried out, and the characteristics of the McKibben type rubber artificial muscle can be predicted. The proposed analysis can be applied to the useful design method.

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A control method of adjusting the stiffness of suspension is proposed for magnetic suspension systems whose bias flux is provided by permanent magnets. In such magnetic suspension systems, zero-power control has often been applied. Since the zero-power magnetic suspension system behaves as if it has negative stiffness, it has been applied to vibration isolation system. However, the amplitude of negative stiffness cannot be adjusted. It is one of the obstacles to the industrialization of the vibration isolation system. In this paper, a proportional feedback is incorporated into the minor current feedback loop of the zero-power controller. It is shown that the stiffness can be adjusted by the gain of the added current feedback. The characteristics of the designed control system are studied both analytically and experimentally.

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A conventional spin-stand system which used to evaluate read-write performance of magnetic recording heads and media can not allow thermal drift of its mechanism and NRRO (non-repeatable run out) of its air spindle motor. Therefore, we proposed a precise track following actuator which applied the spin-stand to construct a piggyback system. The actuator called Nano Motion Actuator (NMA) by the authors consists of a piezoelectric element and a displacement amplifying mechanism. In this paper, a design method of a PID controller to realize a specified gain crossover frequency for the NMA is proposed. At first, we discussed about a model matching problem of an open loop transfer function and decided PID gains from physical parameters of the NMA. Next, based on a loop shaping method, the properties of the frequency response of the open loop transfer function were improved. The effectiveness of the proposed method is illustrated by the simulation results and experimental results.

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Arrangement of steering wheel switches is vital for safe and easy maneuverability of the vehicle. In our previous study, following result was presented, 6 swithces arranged on the middle or upper area of steering wheel can be handled more easily than those on the lower area as used before on the market. In this study, considering that the number of steering wheel switches is expected to be increased, maneuverability of 8 switches arranged on the upper and left area of the steering wheel was studied. Maneuverability of 4 kinds of switches were studied using our driving simulator, 8 switches on the left upper side were found to be the best, as the eye travel from the forward scene to the target is shorter.

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It has been shown in our previous report that DYC is not compatible with the tire force usage equalization and it is important to consider total tire force F_x and F_y as feedback signals for DYC being compatible with the tire force usage equalization. However the driving stability of the electric vehicle is affected how the weighing matrix's coefficients of the criterion function are chosen because our control logic based on the optimal control of the yaw moment, total tire force F_x and F_y, and the tire force usage equalization. In this paper, we proposed a method for the determination of the weighting coefficient of our control logic with quality engineering. By using this, we can make clear the relation between the optimal control error and the driving stability of the electric vehicle how the weighting coefficients are chosen. It was found that the controller using the optimal control having the weighting coefficients determined by the quality engineering method has robustness for the driving stability in various driving conditions. Therefore, it was effective to use quality engineering for vehicle dynamics control.

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This paper is concerned with the constructing of driver-vehicle-environment model for analyzed interaction between drivers and vehicles. We obtained different result of the fuel consumptions between two professional test drivers on mode-test in previous works. Therefore, it should be concerned with that not only the vehicle characteristics but also the interactions between drivers and vehicles on the assessment of fuel consumption. So we focused on the interactions from the viewpoint of driver-vehicle-environment model, especially, the longitudinal control interaction of driver-vehicle-environment on heavy-duty vehicles. First, the driver's operations are enumerated by using of analysis of the experimental result. Next, the information which is perceived by the drivers is considered on each operation. After that, driver's operations are modeled by the multiple regression analysis using experimental result. Finally, the confirmation of the model is performed by the closed-loop-simulation which is composed driver-vehicle-environment model and the vehicle model. As a result, the difference between simulation result of constructed model and experimental result is compared, and then the validity of the constructed mode is clearly.

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Conditions of railway track have conventionally been maintained with exclusive inspection vehicle. If the conditions of the track can be inspected by using service vehicles with condition monitoring system, more efficient maintenance would be possible. This paper describes the development and the verification of the "probe system" which estimates the track conditions without sensors on bogie. To detect the track conditions from the data which can be observed in the interior of a service vehicle, two methods have been proposed: the method to detect track irregularities using RMS of the lateral/vertical accelerations and the rolling of the vehicle body, and the method to detect rail corrugations from the interior noise using the windowed Furrier transform. The probe system including two proposed methods has been developed which is composed by an accelerometer, a rate gyroscope and a microphone for detection of track conditions; a GPS for the localization; and notebook PC for the analysis. The developed system has been installed onto the cab of a service vehicle to carry out a field test for the validation of the system. The results of comparison with the ground data show that the probe system can estimate effectively the amplitude of track irregularities, the grade of rail corrugations and its location.

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In the early design process, it is difficult to apply the conventional engineering design method from the necessity of the setting of the objective function. Therefore, in the past study, the emergent design system which is applicable for the early design process is proposed, and in an application to the design object without connectivity number in the form generation space and with number of elements of about 10^4, effectiveness of deriving diverse design solutions using this system is indicated. In this study, we applied this system to a large-scale design object (a body in white) that has one or more connectivity number in the form generation space and number of elements of 10^5 or more, and it contributed to construction of this system.

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Service robot is facing for the infancy stage as a new industry due to various needs of society such as limited production way for a wide variety of products, labor shortage accompanying the reduction in the younger age population in the coming aged society. Service robot is a machine equipped with potential harmful hazards to human being, but the conventional safety principles for industrial robot such as the principle of separating (safeguarding) or the principle of stopping often deteriorate the functionality of service robots. Therefore it is essential to create a new safety principle especially for service robot. Adequate safety sensors are not yet available on the market and thus the development of the inherent safety design are particularly required. In case of industrial robot educated workers are to operate the robot, but in case of service robot consumers including children and aged people come in touch with them, therefore the risk in the later case is usually higher because of much wider variety of operational conditions. It is crueial effective to clearly decide the "limitation of machine", e.g. target people, operating place and time etc. In this paper, the effective ways to reduce risk based on the limitation of machine and inherent safety design according to the relevant standards on safety of machinery are discussed and proposed a conception of ΔR, the stepwise reduction in risk, to reach adequate reduced risk (ARR).

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Various sensors have been introduced as theft prevention of the automobile as well as their commodities. Improvement in the effectiveness of crime prevention can be expected when sensor fusion techniques are used to achieve an intellectual and integrated judgment system. In this paper, we propose a security system that can detect two or more theft events of a particular automobile using a single sensor. We investigated how a loudspeaker can be used as the sensor. Since there are various events involved in the automobile theft, we target generated sounds from (A) opening a lock, (B) opening a hood, (C) opening a trunk, (D) picking, (E) opening and closing a door and (F) switching on an ignition switch of the engine. The generated sounds from the five theft events ((A), (B), (C), (D) and (E)) were measured with the loudspeaker. Next, two peak values were requested by signal conditioning. Neural network was used to provide relation between these values and five events. As a result, this method we suggested was able to distinguish the five events.

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The aims of the multi-objective design optimization are to find the pareto optimal solutions, and are also to analyze the trade-off between the objectives. The interactive multi-objective design optimization based on the Satisficing Trade-Off Method (STOM) is used in this paper. Especially, the trade-off matrix to analyze the trade-off between objectives quantitatively is introduced. Each element of trade-off matrix consists of the projection matrix of active constraints and the gradient of objective functions. Additionally, it is possible to determine the new aspiration level by using the trade-off matrix. To obtain the new aspiration level, the compromise point and solution are defined by using the trade-off ratio. To obtain the compromise point, the designer input the trade-off ratio between objectives and can obtain the new aspiration level. It is also possible to apply the trade-off matrix to the automatic trade-off method, which is a method to determine the new aspiration level. Through basic numerical examples, the validity is examined.

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In conjunction with recent trends in vehicles getting larger and tires gaining larger footprints, the EPS rack thrust force has been required increased considerably. In a pinion assist type EPS system, the rack and pinion, which are steering gears, have loaded the rack force from the tires. Therefore, high strength rack and pinion have been required to be installed into the EPS system. To address the issue, the authors examined fundamental factors that cause the deterioration of the rack and pinion from the standpoint of the working of the gears. As a result, the significant issue with mesh of the gears has been found by means of static analysis of rack rotating and examination of the working of rack and pinion. And it has got possible to create a solution to address the issue based on a static model with mesh of rack gear, which leads to a new design method for high strength rack and pinion.

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In the present paper, a plate model has been introduced to the computer program for simulation of gear shaving. In the model, tooth deflections of gear to be shaved and shaving cutter are estimated on the basis of plate bending theory. Furthermore, the tooth deflections depend on cutting performance of shaving cutter, so that the cutting performance is evaluated from screw parameter and cutting speed. The calculated tooth profiles of shaved gears with the developed computer simulation program show better agreement with measured ones than the previous program.

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Crown rollers are often used in the flexible media transport mechanism consists of a rubber layered roller and a steel roller. In this paper, the flexible media transport characteristics of crown roller is investigated theoretically. The purpose of this study is to analyze the flexible media transport characteristics such as axial distribution of normal force, nip pressure, traction, and to develop the design method of crown roller that has desired characteristics. First, a numerical analysis method of a contact problem between a rubber-layered roller and a mated steel roller using the results of two dimensional contact analysis was established. Second, two types of crown rollers, i.e. a steel roller with crown shape in its outer radius and a rubber roller with crown shape in its inner radius, were examined. And based on analysis results, a design approach of crown shape which can realize uniform axial distribution of normal force, nip pressure, traction, was proposed. And the flexible media transport characteristics of crown rollers and the characteristics for error load were shown numerically. Last, designed crown rollers were fabricated and the performances of them were confirmed with experiment.

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Carbon Nitride (CNx) coating showed superlow friction when it slid against a Si_3N_4 ball in dry N_2, and this phenomena took place nitrogen atoms desorption from topmost layer of CNx and structural change from CNx to graphitic layer. However, it was taken place after several thousand friction cycles, so-called running-in period. In this study, we proposed Carbon-overcoat deposition on CNx due to shorten the running-in period, and investigated the effects of its thickness on running-in period, minimum friction coefficient and specific wear rate. 5 different thickness specimens as 0 meant an as-deposit CNx, 3, 5, 10, and 15nm as Carbon-overcoat which were deposited on CNx coating by IBAD (Ion Beam Assisted Deposition) method. Tribological measurements of these coatings sliding against Si_3N_4 balls were carried out with a pin-on-disk apparatus and 5 different thickness disks in matched pairs under a 0.1N normal load, 0.13m/s sliding speed, in N_2. The minimum friction coefficient was within a range of 0.01-0.015 when 3nm thickness Carbon-overcoat on CNx coating slid against a Si_3N_4 ball after short running-in period (around 400 cycles) rather than other specimens, and 1.8×10^<-8>mm^3/Nm as minimum specific wear rate was obtained. Furthermore, Raman spectroscopy indicated that Carbon-overcoat specimens changed CNx to graphitic layer easier than only CNx coating.

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On the hydrodynamic slide bearing, friction force acting on the slider varies with the sliding speed and this is the main constraint for accurate positioning in slide bearing. In order to reduce the friction dependant on sliding speed under oil lubrication, the effect of various micro-patterns with different shapes or directionality on friction dependant on sliding speed. In addition, the effect of sliding speed on oil film thickness and pitching angle of slider were also observed. According to the friction test results, friction dependant on sliding velocity under hydrodynamic lubrication of oil was decreased with micro-patterns. And such effect was the most outstanding in the case of that micro-grooves were fabricated on the slider surface for the 45 degrees direction for sliding direction.

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A numerical method for analyzing the elastic contact mechanics due to Lennard-Jones (LJ) surface forces between a spherical slider and a flat disk is presented by taking account of roughness contact effect. First, neglecting the effect of attractive force at asperity contact, various features of elastic contact of 2-mm radius slider are presented in relation to the distance between mean roughness heights. It is revealed that the contact behaviors at a small mean roughness height distance can not be predicted either by JKR or DMT theory. A simple equation to evaluate LJ adhesion force after contact is presented. Next, contact characteristics of 1-μm radius sphere and disk are presented to examine how LJ attractive force at asperity contact can be evaluated. It is found that the adhesion force can be approximated by JKR or DMT theory if the surface energy can be related to Hamaker constant properly. Then, a simple equation to evaluate LJ attractive force at asperity contact is presented for the roughness contact analysis.

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The experiments of cold rolling were made using stainless steel (SUS430) sheets and three kinds of Iubricants in viscosity with rolls polished by #800 polishing paper in the axial direction in the 1st pass, and with rolls polished by #800 one in the axial direction and by #2000 one in the random direction in the 2nd pass. Then, the surface features of sheets rolled in the 1st and the 2nd passes were investigated to discuss the improvement of the surface characteristics of sheets rolled in the 2nd pass. As a result, it has been shown that the 2nd pass rolling with rolls polished by #2000 polishing paper in the random direction after the 1st pass rolling with rolls polished by #800 one in the axial direction gives the disappearance of the nearly linear defects in the normal direction to the rolling one, which occurred in the 1st pass rolling, and gives the increase of surface gloss by using the lubricants of lower viscosity.

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In railway vehicles, rubber bushes have been widely used to fix oil dampers to axle boxes, truck frames and car bodies. The rubber bushes elastically support an oil damper to restrain generation of bending stress in the damper. Increasing the stiffness of the rubber bushes in the principal direction, however, is effective for improving responsiveness of the damper. This paper reports the newly-developed rubber bush which has higher stiffness in the principal direction and lower stiffness in the prying direction compared to those of the conventional one. Load test results demonstrate that the performance required in the specification is satisfied and the vehicle running test result shows that the rubber bush works effectively under the actual running conditions of railway vehicles.

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