This paper described nonlinear vibration analysis using finite element method for automotive wiper. The characteristics were studied by modeling the arm of wiper with damped elastic body used finite elements, and the blade with nonlinear springs. For the arm, the constraint condition, and the characteristics of the spring and damping at the joint were tuned according to the results of experimental modal analysis. Characteristics of stiffness of blade rubber were identified by experimental measurement. The eigenvalue analysis of the FE model were conducted, and the results were used to calculate nonlinear resonance responses using harmonic balance method. Then the experiment verification was performed for the resulted resonance response and the effectiveness of this analysis method was confirmed.

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We have developed a technique for estimating damped vibration of automotive body panels with sound-proof structures. It calculates damping properties for sound-proof structures involving elastic body, viscoelastic body and porous media. For elastic and viscoelastic body displacement are modeled using conventional finite elements including complex modulus of elasticity. Both effective density and volume elasticity have complex quantities to represent damped sound fields in the porous media. Particle displacement in the media is discretized using finite element method. Displacement vectors as common unknown variables are solved under coupled condition between elastic body, viscoelastic body and porous media. Further, explicit expressions of modal loss factor for the mixed structures are derived using asymptotic method. Eigenvalue analysis and frequency responded were calculated for automotive panels laminated with viscoelastic body and porous media using this technique, the results almost agreed with the experimental results.

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Transient Statistical Energy Analysis (TSEA) is a suitable tool to predict transient sound and vibration responses especially in huge structures like ship-buildings under the shock excitation. This paper discusses an experimental verification method for TSEA prediction results. TSEA prediction has no information on the distributions inside of subsystems. The issue for discussion is how to evaluate the representative responses on a subsystem in measurement. Then we firstly carry out the measurement of the transient vibration energy responses on a structure, which has two flat steel panel subsystems. The accelerations at 70 points on the subsystem are measured under the impulsive excitation. As a result, we propose the verification method, in which the transient responses are averaged and the spatial average of measurement point coordination should be at the gravity center of the subsystem. It is also shown that the method is useful to verify the TSEA predictions for two systems, one is composed of two flat rectangular panels and the other is of two flat triangular acryl panels.

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For the passive isolation systems, the ordinary friction damper of constant friction force has performance limitations, because the isolation characteristic declines and the displacement remains apart from the equilibrium position after the disturbance disappears when the friction force is large. In order to overcome the above drawbacks of the ordinary friction damper, a new type of friction damper is proposed in our previous paper. This is achieved by use of an inclined lever, which contacts the cylindrical block by means of a rotational spring, causing the normal and frictional forces at the contact surface to vary according to the displacement of the cylindrical block. However, sprag-slip vibration occurred in the experiments. This paper investigates the cause of the vibration and the design to prevent it. For this purpose, dominant vibration is investigated by the experimental modal analysis. Then, the analytical model is proposed to simulate the problem and estimate the effect of improvement. The model takes into account deformation of the lever, contact surface and pivot support. Results of the numerical simulation showed vibration characteristics similar to the experimental result.

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This paper is concerned with an active wave control method of a rectangular panel. It is the purpose of this paper to present a wave filtering method for the panel using smart modal sensors and its application to an adaptive feedforward control system. Firstly, a wave solution of a rectangular panel is derived to describe the wave dynamics of the structure. This is followed by the proposition of the design procedure of the wave filter using smart mode sensors. Then, from a viewpoint of numerical analyses, accuracy of the proposed method is verified using condition numbers of a filtering matrix. Furthermore, a multi-rate technique is introduced for approximation of the sub-filters in the wave filter, which reduces the computational burden. Finally, experiment on an adaptive feedforward control system using the proposed method is carried out. It is found that the reflected wave absorbing control enables the inactivation of vibration modes.

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We made a test apparatus which consists of a cantilevered beam onto which a primary mass with an impact damper was attached to the free end of the beam. We measured the acceleration time history of the primary mass when the frequency of the foundation excitation was swept up under the constant magnitude of the acceleration of the foundation while changing the clearance between the impactor and the wall of the primary system. The experimental tests indicate that the acceleration level decreases at resonance when the number of the impactor increases. We also created a simulation program to calculate the vibration response of the impact damper, and verified that the calculation result was in accordance with the experimental one. Furthermore, we calculated mechanical energy of the vibration system to explain the mechanism of damping in the case of multi-impactor.

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New approach to estimate sound transmission loss of a wall in a low frequency range is developed. Conventional TL estimation needed the acoustic rooms which have enough large scale to realize diffuse sound field. The main advantage of the method proposed here is no need of these facilities. In executing this method, only hammering test data is used and these data is processed to extract modal parameters of the wall. Using these modal parameters and the supposed rain-drop force on the wall which simulates the reverberant sound field, dynamic response of the wall is calculated based on stochastic vibration analysis. The total power radiated from the wall is estimated and as a result, TL of the wall is achieved. This method is applied to the mockup test of simply-supported plate and the results showed very good agreement with the analytical results based on incident sound plane wave model. As a result, this method is proven to be effective and reliable tool to estimate sound transmission loss of sound insulation wall.

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Vacuumed electric water heater is useful for heat storage. However, it is still required to reduce its noise at boiling and to add the function of rapid heat storage. Therefore, a new heating method is proposed where both the main heater installed at the bottom and the sub one installed at the top are used. We investigated the process of bubble generation and its collapse in relation to the noise reduction mechanism with main and sub heaters used. From experimental results, we propose the optimal tune-up condition how these heaters should be controlled. It is also found the heat storage layer is robust to thermal disturbance and the necessary time for supplemental heat storage can be reduced nearly to 1/4 compared to the conventional one. We confirm that the proposed system is useful for industrial application.

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The acoustic characteristics of lined ducts, especially the attenuation per unit length of lined ducts have been obtained by various simple prediction methods such as the Sabine's Equation, the Bruel's Equation and the Doelling's Equation. However the availability of these methods has not been clarified yet. This paper describes the experimental method and results on characteristics of the lined suct. The comparison between the results of predicted attenuation and experimental one was carried out in order to clarify the usable frequency range of these prediction methods and its availability of each prediction method. As a result, it was clarified that the applicable frequency region of these methods became clear and the Doelling's method was the most useful in the fiber type acoustic absorbent.

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An air conditioning equipment is usually set to keep a rail vehicle comfortable. However its noise is annoying especially when the vehicle is stationary. The noise reduction is very important from the point of view of keeping the car interior space comfortable and is one of the differentiating techniques for the manufactures. This paper describes acoustic and flow noise characteristics of the bending duct. The experiments were carried out in various parameters such as the absorbing ability, bending numbers and flow velocities by use of the bending duct. As a result, it was clarified that the noise reduction effect due to the bending is proportional to the number of times of bending. Moreover the reduction of pressure losses by use of the guide and the airfoil is very effective to the noise reduction.

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The noisy sound propagated from the machinery should be reduced to maintain silent environment around the machinery. To achieve such the requirement, the nearfield acoustic holography (NAH) has been developed for sound source localization, and the information of the source locations is utilized to make the machinery silent effectively. While actual machinery has complicated shape and three-dimensional extension of the structure, the NAH provides planer reconstructed images. It is difficult to grasp the three-dimensional source locations with only a planer image. In addition, when the true source is not on the surface of the machinery, the structure of the machinery around the true source might interfere the assumption that the sound propagates in free field. In this study, the model source is used in the experiment, that has a loud speaker, and the baffle plate which is located in front of the loud speaker. The sound propagated from the loud speaker might be reflected and diffracted by the baffle plate. It is proposed that some measurement apertures should be located around the source to solve the three-dimensional source locations, so a compact two-dimensional microphone array is used to move it easily around the source. Source localization is carried out by the NAH with a small number of microphones of the compact array, and requirement of the filtering on the spatial Fourier domain is mentioned. It is proved experimentally that the sound source localization is achieved properly. The experimental results are discussed with numerical results solved by the boundary element method.

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In this paper, we deal with an obstacle avoidance control problem for a mobile robot. Recently, obstacle avoidance problem has become one of the important issues. Usually, obstacle avoidance problem is dealt as a constrained control problem. Optimal control technique is used for formulating the problem in our approach. Basically, circular obstacle is assumed in this paper. Firstly, we introduce a virtual space and the obstacle avoidance problem is formulated into an unconstrained optimal control problem. In the virtual space, the obstacle avoidance problem is represented as an unconstrained problem. However, note that a descriptor expression comes out in the virtual space. Therefore, we propose a technique to obtain a solution for the descriptor form. Finally, the effectiveness of our approach is shown through some numerical simulations.

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In this paper, a new perturbation method is proposed, and is shown that the correction vector can be calculated shorter than ever. And, the computing efficiency of the response surface optimization method could improve greatly by applying perturbation method with complementary term to example analysis in the optimization of vibration characteristics by the response surface methodology and by finishing eigenvalue analysis which takes most computing time just once. Moreover, the validity and effectiveness is examined by examples by inducing approximately estimated formula of the vibration response value based on orthogonal polynomial. Lastly, it is shown that the computing time is shorten greatly compared with former method by applying this method to analysis of optimization problem of vibration characteristics.

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This paper presents a reduction method of degrees of freedom for the absolute nodal coordinate formulation (hereafter called ANCF), in the case of three-dimensional beam, by applying a component mode synthesis method. We paid attention that the bending stiffness term expressed by the continuum mechanics approach of the ANCF beam element is constant, and proposed a method called C-ANCF which applies Craig-Bampton method to this term. Three numerical examples that compare the C-ANCF and the conventional ANCF are demonstrated to verify the accuracy of the C-ANCF. As a result, it is shown that the C-ANCF is able to be extended to three-dimensional beam behavior by verifying that C-ANCF shortens computing time, while keeping the acceptable accuracy of the expression characteristics of ANCF on large rotation and large deformation in the numerical examples. It is also shown that shortening of the computing time in the case of three-dimensional beam becomes larger than that in the case of two-dimensional beam.

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In this paper, we propose a four-bar linkage mechanism representing competition and cooperation. For this purpose, we propose a Single Bistabile Pendulum (SBP) mechanism of simple mechanism that have bistability by magnetic force and ferromagnetic cam. And we propose a four-bar linkage mechanism that have quadri-stability, connected the pendulum points of two SBP mechanisms by link. We obtain a basin of attraction of the four-bar linkage mechanism experimentally. Moreover, we derive a analysis model of the four-bar linkage mechanism, and obtain a basin of attraction of the analysis model numerically. Then, we compare a basin of attraction of the four-bar linkage mechanism with the analysis model. The result shows that the analysis model is suitable as a analysis model of the four-bar linkage mechanism.

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To improve noise and vibration quality of mechanical structures, it is important to identify excitation force spectra and the positions at which the force acts. Matrix inversion method is the most frequently used technique for input identification. In this method, excitation force spectra are identified from the inverse problem based on the frequency response function (FRF) and acceleration, which is measured under operational conditions. Although the matrix inversion method is popular because of its simplicity, the identified force can be influenced by measurement error. Therefore, the identification accuracy should be statistically evaluated. To address this issue, in this paper, a variance estimation method of the force spectra identified by the matrix inversion method is proposed. The variance is estimated on the basis of the variance and covariance of FRF, and the proposed method is validated via a numerical model. In addition, the variance estimation method is applied to a vibration test to compare the reliability of the force spectra determined using the estimated variance with the condition number of the FRF matrix, which is also known as an error-propagation indicator of the input identification. Finally, it is proved that the proposed method is suitable for accurately evaluating the identified force.

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It is important to recognize surrounding environment from on-board vehicle sensors for driving support system. A stereovision system is among the most practical approaches to this problem, and we have reported on an obstacle detection method using short-baseline stereovision system, which can be installed behind the rear-view mirror of the vehicle. However, there were problems that it produced some false positives, and deteriorated measurement accuracy. In this report, we propose an obstacle detection method using Occupancy Grid Maps to solve these problems. Moreover, a detection method of moving objects is also proposed. From some experiments, it was confirmed that problems arising from shortening baseline length of stereovision were improved. Moreover, moving object can be detected from far position even though the short-baseline stereovision system is used.

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We propose position and attitude control method of Eye-In-Hand Robot by Dynamic visual servoing based on Virtual Spring-Dumper Hypothesis using Binocular Visual Space Error. We obtain the 3D position and attitude error from the binocular visual space error using Jacobian between cartesian space and binocular visual space. The proposed method is robust to calibration error of camera angles, because it does not use camera angles to calculate feedback command. Simulation results are presented to demonstrate the effectiveness of the proposed method.

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In this paper, we propose “double admittance control” for a finger & manipulator system, which can realize different admittances of both the finger and the manipulator. The proposed method can realize very natural motion to constrained tasks and can compensate a finger-manipulability under the admittance control. Although our previous method can compensate the finger-manipulability under finger admittance control during the constrained task by using compensate manipulator motion depending on an optimum theory, these results can realize only artificially-made motions. On the other hand, as the new proposed method uses natural dynamic effects, its system is very simple and its motion is very natural. Consequently, this new proposed system has a possibility to extend the manipulator technology to biomechanical control field.

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Some manipulation tasks have a direction of end-effector acceleration of a manipulator and directions for which dynamic accuracy is required in the motion. The author has proposed the index (DAIT: Dynamic Accuracy Index for Task-directions) that allows us to evaluate the dynamic accuracy of manipulators considering the task-directions. However, the DAIT was only applicable to non-redundant manipulators. In this paper, we first extend the DAIT to be applied to redundant manipulators. Next, some postures of a planar 3-DOF manipulator are analyzed on the basis of some indices that have been proposed and the DAIT. Finally, we discuss the usefulness of the DAIT in determining the optimal posture of the redundant manipulator for a given task.

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New measuring and training method of muscle power for senior age, that utilizes small 'electric generator' instead of 'spring force', is described in this paper. Our study clarifies that this method can measure not only the muscle power, but also the reflection time and the muscle strength without any physical stress on senior aged subject. Meanwhile, another advantage of employing electric generator is that generator can electrically produce regeneration resistance as the load for rehabilitation. This paper also describes whether the developed system can be applied for physical training. With a view of physiotherapist, various investigations were executed. The evidences show the efficiency of the developed training method and the developed system.

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There are many researches to identify operator's dynamic characteristics in manipulating human-machine interaction systems. Analyses of operator's dynamic characteristics provide a clue to develop human-friendly systems that assists skill development. However, these researches mainly discuss single hand operations, and there seems to be little researches for two hand (bimanual) operations. To develop useful operational systems, the analyses of operator's dynamic characteristics in bimanual operation are indispensable. This research aims to clarify proficiency of operator's skill in bimanual operation. Concretely, the proficiency is evaluated by using an experimental human-machine interface for bimanual operations that provides three different mechanical impedances. The characteristics of operators are evaluated by tracking performance to references generated randomly and skills to draw geometric patterns in a two dimensional plane. In the experiment, the extent of proficiency was also compared with each other for the three different mechanical impedance models. It has been confirmed that the proposed evaluation method can successfully clarify the extent of proficiency of operators' skills. It was also observed that there was little difference in the extent of proficiency among the three mechanical impedances.

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A handshake is an embodied interaction to display closeness using physical contact. In the case of a handshake between a human and a robot, robots can now smoothly communicate and coexist with humans without eliciting feelings of aversion in humans. To enable such a handshake, we proposed a model that simulates a handshake approach motion by analyzing the human-human handshake motion. With this model, a robot generates a handshake motion when a handshake is requested by a human. However, embodied interaction between a human and a robot can be promoted if, instead, a robot requests a handshake from a human. Therefore, in this paper, we propose a handshake request motion model with which a robot requests humans for a handshake. In this model, a robot stretches its hand out to a human to request a handshake. Furthermore, a gaze presentation is generated based on the analysis of the handshake between humans. A handshake robot system with the proposed model is developed, and the effectiveness of the model is experimentally demonstrated.

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This paper presents a new methodology of attitude estimation for cost-effective and small-size inertial measurement units, consisting of tri-axial gyroscope sensors, accelerometers and geo-magnetometers. Introduced for the algorithm development is a quaternion feedback structure, where bias terms in the gyroscope rate information, appearing in the phase-locked loop, are identified with the theoretical guarantee of the global and asymptotical stability. The bias-term identification and modification process is performed continuously without the influence of the disturbance by applying the proposed disturbance detection scheme and a conventional vector matching method. Practical validity of the presented framework is fully evaluated by experiments. The evaluation result shows that the approach in this paper can offer superior drift-free performance with property of disturbance rejection under arbitrary high-frequency test motion of spatial rotation and translation.

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In human-machine cooperative lifting system, it is very important issue to estimate the operator's intention such as the ‘lift up’, ‘move down’, ‘rotate’ and so on. This paper addresses how to estimate the operator's intention using EMG signals, in particular, focusing on the discrete/continuous aspects of the operator's intention. The discrete intention represents a kind of ‘mode’ and is estimated by using the logistic regression model. The continuous intention, which can be regarded as a magnitude of the specified motion, is estimated by using the PCA. Finally, the proposed cooperative lifting system is realized which includes not only the translational but also the rotational movement in two dimensional working space, and the usefulness is demonstrated.

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The problem of avoidance of science and technology learning is one of the big issues for education in Japan. Part of the problem might arise from the lack of experiences of so-called ”monozukuri” or engineering design activities at elementary school levels. Hands on class room activities for elementary schools are developed including the followings. 1)Visual contents including robots in the real world, earthquake disasters, and robots engaging in rescue missions, 2)Using the same kind of body frame of the vehicle robot, four different types of prototype cars are prepared, which enable pupils to find the difference of the effect of gear-ratio, 3)Small cardboard parts called ”parts card” for each component of the robot which enables pupils to develop their design by manipulating and placing the card to the body frame, 4)Mechanical models varying from simple to complex, multi-link structures. The results of the pre-post questionnaire shows that over 70% of pupils have positive feelings to ”monozukuri” and shows 10% increase. The parts card facilitates design resulting that almost all design requires only minor modification. The image map method is used, the numbers of the concepts are increased by four points and its quality is improved. One of the objectives of this project is to enhance empathy; the ability to relate well to others. We examined the designs of pupils and found that a variety of equipments are added for disaster victims.

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This paper proposes a formulation method on comprehensive evaluation of plural muscle load by applying the methodology of multi-objective optimization. Muscle loads are formulated as objective functions that should be minimized, and comprehensive evaluation of muscle loads is formulated as a multi-objective optimization problem. Design of handrail position for sit-to-stand movement was used as the case study of the proposed method. The height and distance of handrail are design variable, and surface electromyography of anterior deltoid, triceps brachii, rectus femoris, and tibialis anterior were measured when participants stood from a chair with handrails. The ratio of the maximum voluntary contraction (MVC) was used as the indicator of muscle loads. Result from the measurement, it is found that the muscle loads of triceps brachii and tibialis anterior have trade-off relationship on the assumption that %MVC indicates the muscle loads. The higher and the closer the position of handrail is, the higher the muscle load of triceps brachii is, conversely, the lower the muscle load of tibialis anterior is. The two muscle loads were approximated as quadratic functions, and formulated as a multi-objective optimization problem. The optimization problem was solved by the satisficing trade-off method, and the Pareto optimal solution for the participants was obtained at which the height is 234 mm and the distance is 585 mm. The comprehensive evaluation of the two muscle loads probably expresses the sense of the participants more precisely than the use of either of the two muscles.

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In this paper, the urgent evacuation behavior of passengers at aircraft accident is formulated as a simulation model which consists of two models such as a two-dimensional grid cell model and an autonomous and multiple agents' system model. The former model represents the layout of cabin interior and the allocation of passengers. On the other hand, the latter shows the behavior of evacuation of passengers from inside of a cabin to outside of an aircraft using emergency equipments such as an emergency exit and escaping slide. This autonomous agent is able to obtain the necessary information for urgent evacuation within one's field of view and decide to select the escaping route by means of obtained information concerned with escaping path to the nearest emergency exit. By the comparable study between the results of the proposed simulation and the accident analysis reports on “Garuda Indonesia Airways Accident on 1996” and “China Airline Accident on 2007 ,” it is verified that the proposed simulation system enable one to estimate the situation of urgent evacuation in the aircraft accident.

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Recently, with rapid progress of the computer hardware and 3D-CG software technologies, the 3D design system such as CAD and CAE, is popularized in manufactures. However, 3-dimensional data is produced now using man-machine interfaces, for example a 2-dimensional mouse and a keyboard, and using intricacy combined operations of those devices. So, designers said, It is far from sensate creation. Spark of imagination doesn't get interested. Therefore, little artistic designers especially jewel designers create using the 3D design system. In this paper, we describe the Virtual-glove using ERF (Electro Rheological Fluid) to feel the 3D virtual objects on operator's hand, propose the new actuator device for the small and lightweight virtual glove. Then we show the characteristics of ERF to reaction force. The results is shown the principle of reaction force using the device was clarified.

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To keep the consumption rate of each part is very important for mixed-model assembly line scheduling in JIT production system. The goal chasing method (GC) and a number of papers have been proposed to achieve the parts usage leveling goal. These methods keep the consumption speed of parts constant as much as possible, and aim to decrease the amount of the stock in pre-process indirectly. In this paper, we set objective function based on the stock in pre-process directly. The function is influenced by different assembly time and delivery cycle among each product. And we have proposed the sequencing method. The method is concept of time-based goal chafing method (TBCG) with consideration in parts delivery cycle. By numerical experiments, effect of proposed method is presented.

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In the design of kansei (emotional) quality, one of the important issues is to extract causal relations between physical design attributes and the customer's emotional responses. Without such relations, a designer has to rely on his/her own sense that may be different from the customer's. In this paper, we propose a new method for extraction of logical rules consisting of combinations of design attributes that explain a customer's emotional judgment towards product appearance. In the method, we apply a reduct calculation in rough set theory to derive alternatives of causal rules between design attributes and emotional judgments, and use the customer's eye gaze features for refining the rules. We extract two types of visual attentions (VA), i.e., a single visual attention (SVA) and a combinational visual attention (CVA), by using the proposed gaze features. To demonstrate the effectiveness of the method, we conducted a sensory evaluation experiment using a car-interior design as a case study. In the experiment, multiple participants evaluated impressions of multiple design samples by selecting from a set of words. During the experiment, we recorded the participants' eye gaze movements as coordinates on a screen, and asked them to vocalize aloud what they were thinking. After an evaluation of each design sample, we conducted a retrospective interview. From the results, we confirmed that the estimated SVA and CVA significantly covered the vocalized thoughts and statements made in the retrospective interview. The estimated VA reduced 53% of the erroneous causal rules and improved the quality of the rules. We found a case where two participants making the same emotional judgments have implicitly different points of view when evaluating the same design sample. Most conventional causality analysis has been unsuccessful in finding such diversity of points of view.

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In recent years, the interest of environmental load reduction has rapidly increased and in particular, the requirement for replacing undiluted working lubricant with diluted one has strongly been demanded in the fields of various metal working. However there are extremely few commercial diluted lubricants in the internal honing, because the lubrication and the viscosity of the lubricants are insufficient for obtaining good surface finish. To address the problem, we have developed a new type of diluted working lubricant for the honing. Then a polymer polyalkylene glycol as a basic agent of the lubricant was optimized and a micelle-forming fatty acid and an alkanolamine were introduced to the lubricant. As a result, the newly developed water-soluble working fluid achieved the same good performances, concretely, low honing forces, large depth of cut and good finished surface as those obtained with commercial undiluted lubricant.

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Ni-Cr cast alloy showed the excellent tribological characteristics at 1000°C in air. In order to examine the relation between the tribological characteristics and the glaze oxide layer, detailed observation and chemical analysis of the layer was carried out. As a result, work hardening in the vicinity of base material interface and refinement of crystal grain within the glaze oxide layer were observed. These structures formation caused strength improvement and formation of harder layer than the base material. Finer crystal grain layer was formed at the outermost layer of the sliding surface, and this layer formation was attributed to decrease shear force. It is considered that, in addition to wear resistance due to the hard layer formation on sliding surfaces, low friction effect was generated by formation of the layer with low shear force on the hard layer, whereby the excellent tribological characteristics were obtained.

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Recently titanium and nickel alloys have become eminent for making aeronautic and astronautic parts. Since both titanium and nickel alloys have very low thermal conductivity, the cutting tool suffers from most of the heat generated during cutting process and becomes severely damaged. Therefore, there is a requirement for a durable tool with excellent control of cutting condition. In this research, the control of tool temperature using the neural network for machining material with low thermal conductivity were developed and evaluated. The neural network between the cutting conditions and the temperatures of tool was firstly made by the teaching data. Then mathematical model using algebra was made by using the neural network. This mathematical model is very convenient tool with simple and economical. Before cutting process, NC program was initially read and the relationship between the optimum cutting speed and cutting time was calculated by using the neural network. Therefore cutting speed was controlled to reduce the maximum temperature on the edge of tool. The temperature on the edge of the tool can be kept at desired value and thus, the tool life will also be kept longer. The optimum cutting speed was used during the cutting. These were evaluated by turning experiments using assayed materials of Ti6Al4V. It is concluded from the results that; (1) Temperature change of tool was controlled by using the neural network during cutting, (2) Even work piece with very low thermal conductivity, the tool life was kept longer by this control method.

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Differential gear machine is often used for a car to smooth cornering. For the complexity that four bevel gears in a differential gear device engage at the same time, there are few papers that gathered up an analytic study about load distribution and tooth root stress distribution on bevel gears. In the case that three bevel gears in differential gear device engage at the same time, authors analyzed load distribution and tooth root stress in previous report. Therefore, in this study, authors analyzed load distribution and tooth root stress in the case that four bevel gears in differential gear device engage at the same time. Load distribution and tooth root stress in the case that four bevel gears engage at the same time were compared with them in the case that three bevel gears engage at the same time. In addition, how assembly errors and crowning influence on load distribution and tooth root stress in differential gear device were clarified quantitatively.

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Nowadays the infrared imaging technology has been developing in various fields. We therefore focus on the infrared ray imagery to investigate the gear tooth meshing. In the present report, a high response infrared thermography was used to estimate the tooth contact of hypoid gear under running conditions. The obtained data was the middle infrared ray image around 4 μm wavelength. Especially, we looked at the increase of temperature on the tooth surface caused by gear meshing. As a result, it is clear that the temperature was affected by contact pressure, relative sliding speed between tooth surfaces and average peripheral speed of tooth surface. This proposed method is effective to evaluate the tooth contact of hypoid gear.

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We developed an involute-cycloid composite tooth profile gear to obtain higher performance than an involute one. The driving performance in the involute-cycloid composite tooth profile gear is influenced by a variation in center distance because of the tooth profile based on cycloid tooth profile. In this study, we calculated the transmission error and the tooth root stress for the various center distances. Further, we examined the driving performance for the involute-cycloid composite tooth profile gear by measuring the tooth root stress and the transmission error.

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This paper proposes a general method for measuring and identifying the geometric deviations inherent to five axis machining centers with a swivel angular head and a rotary table. The structural configuration of this machine is one of mixed five-axis machining centers. If the inclination angle of C axis is an initial value and its angular deviation is also superimposed on it, the inherent geometric deviations are same as multi-tasking machines, which have ten inherent deviations. The circular motion of simultaneous four-axis control around the tilt C-axis is newly proposed in order to measure the circular trajectories and its eccentricities. The measurement of simultaneous three-axis motion around the B-axis is also required to identify the inherent deviations. In this paper, mathematical relationships between geometric deviations and eccentricities of the trajectories are derived and then the procedure for identifying the deviations using the expressions was clarified through numerical experiments. It is also pointed out that six measurements are needed to identify the inherent deviations when the inclination is zero.

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It is difficult for a designer to optimize a plant layout design because the related decision making involves multiple objectives and constraints such as safety, economic costs, maintainability, and construction term of works. In order to support the designer's decision making, we have developed a multi-objective optimization system for plant layout design; this system involves an effective interaction between the designer and the computer. In this paper, we have proposed a hybrid optimization technique for plant layout design using a genetic algorithm (GA) and particle swarm optimization (PSO). In the first step, the designer globally searches for a layout solution on the basis of a coding rule of the GA proposed in the first report. However, the obtained layout solution in this step is rough and is not adequately optimal because the GA is a combinatorial optimization algorithm that uses discrete design variables. Then, in the second step, the obtained layout solution is automatically corrected toward a better position by using a modified PSO algorithm for continuance design variables. The proposed method is applied to the layout design of an actual power plant in order to demonstrate the validity of this approach.

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