As a basis for developing experimental identification techniques for rotating machinery, the authors proposed in previous papers an experimental identification technique for linear and nonlinear rotating shaft systems. The proposed technique is based on the principle of harmonic balance, and is classified as the frequency domain technique. The technique requires data of periodical responses of the system. To obtain this type of data is not always convenient. Thus another technique free from this inconvenience is of use. In this paper, a new experimental identification technique is proposed. The proposed technique is classified as the time domain one. Two variations of the technique are proposed. The first method is based on the usual least square method. The second is based on a minimization method for a problem with constraints. The latter usually yields better results. But in this method, an iteration procedure is used, which requires initial values for the parameters. As the initial values, the results of the first method can be used. So both methods are of use. Finally the applicability of the proposed technique is confirmed by numerical simulation as well as experiment.

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The effect of rocking motion of the anchored and unanchored flexible cylindrical storage tanks on sliding response due to the seismic excitation is investigated. The five-degree of freedom model is developed in order to examine the seismic response of them. This model is able to take account of the coupling behavior between sliding and rocking, the flexible deformation of the shell and base plate. The validity of the presented mechanical model is demonstrated by the shaking table experiments with large and small model tanks. It is clarified that the taller tank is easier to slide than the broader ones by simulation results obtained by parametric study for actual size tanks.

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This research deals with the nonlinear response behavior of rocking vibration associated with impact and sliding on the rocking motion of rigid block under two dimensional sinusoidal excitation of horizontal and vertical direction. The nonlinearities of the rocking vibration strongly depend on the impact between block and base, which should induce abrupt reduction in kinetic energy, and sliding motion which occurs during rotation and impact. Particularly, when the oscillation direction of base is varied, the rocking vibration as well as sliding motion are strongly influenced by the change of oscillation trajectory. The chaotic responses are observed in wider region, when the frequencies of each excitation direction are different. The complex behavior of chaotic response, in the phase space, is closely related with the trajectory of base excitation and the sliding motion.

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The authors have been developing magnetic rubber dampers with a constraining layer (MRDC). They are generally installed on vibrating steel plates with the magnetic attractive force of the magnetic rubber layer. The damping performance of these MRDC depends mainly on the frictional loss due to the relative slip motion arising between the magnetic rubber layer and the vibrating steel plate. In the previous paper, the flexural vibration of a beam with a sheet of MRDC was theoretically analyzed by taking the frictional loss due to the relative slip motion into account and the equation to calculate the loss factor of the beam with a sheet of MRDC was derived. In this paper, the modal loss factors of the beam with a sheet of MRDC were calculated based on the derived equation, and those calculated values were compared with the data obtained experimentally using the method of resonance. Also, the relationship between the loss factor of the beam with a sheet of MRDC and material properties-magnetic attractive force, the content of ferrite powder, the thicknesses of constraining-, magnetic rubber-, and base-layers has been discussed.

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A measuring method for the transfer matrix parameters of acoustic systems by using 3-microphones is described in this report. The acoustic characteristics of engine intake systems are usually analyzed by the transfer matrix method. However, there are some intake subsystems for which there is still no adequate theoretical representation. By using the 3-microphones method, the matrix parameters of unknown systems can be determined experimentally. The matrix parameters of an air cleaner were measured and used to predict the acoustic characteristics of the intake systems. The comparisons were made between predicted results using the matrix parameters and directly measured results with mean flow. Agreement in fairly good and it suggests that this method can be used to evaluate the acoustic characteristics of intake systems with low speed mean flow. Furthermore, this 3-microphones method was applied for measurement of the acoustic characteristics of sound absorbing materials. The propagation constants and the characteristic impedance of some materials were measured and compared with measured values by using the 2-microphones method. The good agreement suggests that this method is also reliable to measure the acoustic characteristics of sound absorbing materials.

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A diagnosis for air-conditioning pipe is important in order to prevent unexpected system failure such as pipe leakage. In this paper, we proposed a diagnosis algorithm to classify a corrosion type and to infer a corrosion size based multiple points measuring data using a pulsreflection method. This algorithm can estimate the corrosion type and the bigger corrosion size than the prove diameter, by measuring at multiple points while the conventional way is not able to do this. Besides it does not depend on pipe diameter. Finally, we experimented on piping with the machined corrosion, and show the utility and accuracy of our proposed algorithm without dependence of pipe diameter.

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The aim of this paper is to realize a sliding mode control system using robust hyperplane based on fuzzy model for active magnetic bearing (AMB) system with gyroscopic rotation. A fuzzy model of AMB system is built from the input and output data of the actual turbo-molecular pump by using fuzzy neural network. The sliding mode controller has a switching hyperplane using μ-synthesis theory which has a powerful robustness and can suppress spillover phenomena. The super high-speed operation test of the actual turbo-molecular pump has been done by using the proposed controller. The good experimental results have been obtained. Therefore, it has been clarified that the proposed scheme is very useful strategy for AMB system.

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In this paper, we consider such a stabilization control for a single inverted pendulum system that makes the pendulum rotating cyclically. We call this a limit cycle control of the inverted pendulum system. First, a realization law of such limit cycle is derived based on the law of mechanical energy conversion. Then, a stabilization control law for the produced limit cycle is designed based on the Lyapunov stability theory. Finally, the stabilization control law is extended so as to ensure not only stability of the limit cycle but also an L₂-gain disturbance attenuation in the presence of viscosity friction and modeling error. The effectiveness of the proposed control scheme is demonstrated via experimental works.

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The authors have been proposed self-powered active vibration control systems, which produce control force using regenerated vibration energy. There are two types for the proposed systems. The one is called a singular type: it achieves regeneration and active control with a single actuator. The other is called a combined type: it realizes them with two actuators. To discuss their feasibility, the authors have been proposed the method to estimate the balance between regenerated and consumed energy. The conditions under which regenerated energy is greater than consumed energy were obtained by this energy balance analysis. In this paper, the practical schemes of regeneration and active control are presented. These systems are realized on experiments and their performance is examined. The results show that the both systems are attainable under the conditions obtained by the energy balance analysis.

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In pneumatic servo systems, the adaptive pole-placement control system is applied to improve the control performance. In many works, the controller structure of adaptive pole-placement control systems is adopted indirect methods. However, the structure becomes complex in this design scheme, i.e., calculating an inverse matrix. So, we note a direct adaptive pole-placement control system. This paper presents a design scheme of a direct adaptive pole-placement control for pneumatic servo systems. In this design scheme, the control input is sympathized without identification of the plant and calculating an inverse matrix. The effectiveness of the proposed design scheme in confirmed by experiments using the existent pneumatic servo system.

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This paper deals with the active control of progressive wave of a simply supported thin plate. It is the purpose of this paper to present a wave control method of a distributed parameter planar structure. This paper also aims to show the results of visualizing wave propagation. Unlike a conventional modal-based control method, this method has the potential of suppressing all the vibration modes of a structure. Particular emphasis is placed on the progressive wave control method that enables the confinement of external energy, a cause of exciting vibration modes, into a restricted area, thereby diverting the progressive wave out of a specific region where vibration is to be prohibited.

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GHP (Gas Heat Pump) is an attractive air-conditioning system that realizes saveenergy and low emission. It however has some difficulties to control, e.g. slow responses, large dead times and the system dynamics easily changed by the operating conditions. In this paper, we propose a learning predictive control method, which is the recursive predictive controller with the function switching the system model according to the operating conditions and identifying the system dynamics in on-line process. We show the effectiveness of the proposed method through the numerical simulations and experiences.

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In a bottle or can filling plant, the beverage should be chilled to an appropriate temperature. A plate heat exchanger is usually applied to do the cooling. In the current plants, the coolant is supplied from two coolant tanks, a high temperature tank and a low temperature one. We propose a new cooling method, which does not require those tanks. The coolant is supplied from the refrigeration unit directly to the plate heat exchanger. The flow of it is controlled, so that the temperature of the beverage at the outlet of the heat exchanger becomes the designated one. A bypass valve is used to control the flow of coolant. In order to improve the response and precision of the control, an observer and a regulator are introduced. Through simulations and experiments at a real plant, we can conclude that our proposed method can be utilized in actual filling plants.

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This paper proposes the Tactile Differentiator that can enhance the edge of polygonal surface through tracing motion. It is composed of a flexible beam anchored at the base with a moment sensor, and an actuator for moving the whole system. When the beam tip passes over the edge where two different planes are intersected with an arbitrary angle, the Tactile Differentiator provides a step change of output, as if it were just like a differentiator. The edge enhancement factor of sensor is introduced with the shape of beam, the intersection angle of environment, and the contact friction. By using the factor, the design orientation of the sensor is discussed. Experimental results are also shown to verify the basic idea.

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In our conventional research, we proposed a new technique to Estimate the Smoothed value and the Differential value of the sensor inputs by using Sliding mode system (ESDS). We smooth the distance value by supposing the continuity of the signal that is obtained by the sonar, and taking advantage of this continuity, we compose an robust estimator. This estimator is based on the sliding mode system. In our proposed method, there is trade off between the ability of noise elimination and the characteristics of chasing the signal. In this paper, we discuss the ability of noise elimination that ESDS has by finding the solution trajectory in the phase plane. At the same time, we discuss the characteristics of chasing the signal by using solution trajectory. According to these consideration, we clarify the relation between these characteristics and the arbitrary parameters.

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Experimental, numerical, and theoretical investigations have been carried out on statics of magnetic bead chain in magnetic field. Chains formed on a solenoid coil were observed and chain lengths and slant angles were measured. It was clarified that the chain length depends on both the density of magnetic particles and the magnetic flux density. It was also clarified that chains have inclinations in the inclined magnetic field and that the inclination of a chain is enlarged by the gravitational force. These configurations of chains are determined to minimize the total potential energy that consists of the gravitational and magnetic potential energy. These characteristics were also confirmed by the numerical calculation with the Distinct Element Method.

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Effective robot functions emerge from not only according to the level of system control i.e. intelligence but also according to conformity between morphology, intelligence, task and environment. This paper investigates the relationship between robotic morphology and intelligence against environmental conditions and the characteristics of functions emerging in evolutionary robotic systems. The robotic system used in the study has a reconfigurable morphology and intelligence, which were designed by genetic programming. The robotic morphology is represented as a graph structure constructed from cells with motor and visual sensors, and intelligence is a computer program defined by a parse tree. In this study, a simulation of a task in which the robot had to maintain a certain distance from an object was executed. The results clarified the importance of conformity between morphology and intelligence, and showed that effective functions emerge as the result of such conformity between morphology, intelligence, task and environment.

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An approach to sensor fault detection and identification (FDI) in the dead reckoning of mobile robots is proposed. It is based on the interacting multiple-model (IMM) algorithm. Changes of sensor normal/failure modes are explicitly modeled as switching from one mode to another in a probabilistic manner, and mode probabilities and estimates from single-model-based filters, each of which is based on a model matching to a particular system mode, interact with each other effectively. To provide better fault decision, a simple decision rule is incorporated into the IMM based algorithm. The proposed FDI algorithm is implemented on our mobile robot. Sixteen system modes (one normal mode and fifteen 'hard' sensor-failure modes) of four internal sensors (two wheel-encoders, a steering potentiometer and a yaw-rate gyro) are handled. Experimental results illustrate that the dead reckoning with the proposed FDI system allows robust motions of the robot subject to sensor failures.

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This paper presents a novel control method for a human-robot cooperative task, i. e., handling or positioning of an object. In order to carry out the cooperative task easily, the motion of carrying the object is alternatively restricted to translation or rotation by changing stiffness coefficients of impedance parameters of a robot. The changing of the motion is determined using an equation of equilibrium of force and torque applied by a human operator. In the proposed control method, a position of a rotation center, i. e., an impedance center, can be changed according to the intention of the human operator who desires high efficiency in the cooperative task. The rotation center is indicated using a gesture by the human operator's index finger with 3-D measurement equipment. The robot carried and positioned a hole part cooperatively together with the human operator to insert the hole part into a peg part. Experimental results illustrate that the proposed control method is suitable for the human-robot cooperative task.

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We are developing a mobile robot platform which works in the actual indoor and outdoor environment. For this purpose, a six wheel vehicle which can travel over 18 cm single step, was developed and tested. The vehicle has six wheels and all wheels are driven using friction wheels. The back and forth wheels in both left and right sides are steered in the opposite phase. Since they can swing up and down by DC motors, the vehicle can travel over a 18 cm step. As one of main feature of this mechanism, bobbin-shaped friction wheels which transfer driving force from main driving wheels to steering wheels located front and rear of the body. This vehicle may be applied to wheel chair or base of mobile manipulator which has to work autonomously in the real indoor and outdoor environment.

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This paper describes an approach to generate a collision-free trajectory for manipulators. The approach has the following characteristics: (1) The joint trajectory of manipulator is expressed with cubic uniform B-spline curves; (2) A performance index function containing all constraint and unconstraint conditions on the manipulator is constructed to evaluate the trajectory, and the value of each weighting coefficient is automatically decided in calculation; (3) The control point values in B-spline curves are optimized by Complex Method algorithm so as to obtain the final trajectory; (4) A simple and practical feature expression is developed for links and obstacles; (5) The collision detection and the collision evaluation are easy and efficient. The simulation and experiment results for an industrial manipulator with 5 links demonstrate the effectiveness of the proposed approach.

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In the social context of an aging workforce at the labor intensive manufacturing sectors, we discuss an assisting system for older workers who have excellent skills though their physical ability to perform iterative tasks at a constant speed with high quality. "Skill-Assist" which is proposed in this paper is a new type of assisting system which varies its mechanical impedance to give workers who have been working under the lifetime employment system a sense of achievement in being again able to accomplish the skilled tasks they were capable of when younger. This paper discusses the control algorithm of Skill-Assist. First, a criterion for changing the impedance of Skill-Assist in response to task condition variations is explained to propose. "Phase-Dependent Impedance Control". Second, desirable impedance patterns are experimentally determined. The patterns are required to produce a good subjective operational feel and precise positioning when maneuvering Skill-Assist. Finally, the effectiveness of Skill-Assist is verified under more practical positioning tasks, which is evaluated based on the subjective operational feel, physical stress, and productivity.

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This paper presents a horizontal transportation system for construction. Although handling of construction materials at construction sites is expected to be automated for improving productivity, it has been difficult because the environment often changes in the construction field. The system consists of an autonomous vehicle and signs. Signs indicating waypoints and the next command are located in the field as landmarks for transportation path. The autonomous vehicle tracks the sign and recognizes instructions from the symbol on the sign using a SLR (Scan laser radar) and a NIR (Near-infrared) vision system. Consequently it moves or handles materials according to the instruction. The system is adaptable to the changeable environment of the construction site because the transportation path can be easily changed by altering the content or placement of the signs. Experimental results obtained in the outdoor environment show feasibility of the system.

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In the Oil-Hydraulic system used in the construction machinery, such as excavator or crane, the improvement of the system operating property is important for the purpose of decreasing the fatigue of the operators. On the other hand, efficiency of the system is also important because of the environmental issue. Therefore optimization of the efficiency and operating property of the oil-hydraulic system is developed on this study. At first, operating property optimization result and efficiency optimization result are compared. Next, the method of simultaneous optimization of operating property and efficiency is proposed. At last, the robust optimization method is adapted under the condition of changing lever operation pattern. In the consequence, it is approved that the drop of the objective function value is minimized under this parameter change condition.

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This paper presents a placement time optimization method of chip mounter system. Placement time changes greatly by the performance of the chip mounter and the configuration of the system. The problem is how to distribute parts and parts feeders to each chip mounter. We propose a distributing method using GA which can be applicable to the various systems. Several numerical experiments about some systems composed of more than one chip mounter with different performance were done. It was confirmed that our proposed method had validity more than conventional method through the results of numerical experiment. Furthermore, practical examples to the produced utility system are shown.

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In the previous study of shock response analysis for linear and nonlinear models representing products, we found the possibility of two kinds of strange phenomena. These phenomena lead to overestimation in the mechanical-shock fragility test. In order to verify these problems as stated above (in the mechanical-shock fragility tests, ex. JIS Z 0119 and ASTM D 3332), we conducted the shock experiments with a real product and an experimental model (which represent the situation that products are stacked). As a result of that, we confirmed that there is a possibility that these phenomena may occur in mechanical-shock fragility tests. The outline of these phenomena is as follows: (1) the critical acceleration of products may depend upon the velocity change of the shock pulse in the critical acceleration test. (The dependency of the critical acceleration on velocity change) (2) there is a possibility that the products may be more fragile reversely when a certain shock pulse with a lower acceleration is applied. (The reverse phenomenon in the critical acceleration shock test)

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In this paper, Clarification of cognition skill in actual machine operation is tried, and a theory to realize effective assist on the basis of the result is proposed. First, it is supposed what cognitive process operators operate machines through, by questionnaires to high skilled operators. Next, cognition skill of a subject in a certain work is clarified with a value named "Information Dependence", using a simulator system that is constructed on the basis of the questionnaire's replies. Finally, a theory to assist machine operators effectively is proposed on the basis of these studies on cognition skill, and the effect of the theory is validated. Also, the possibility to generalize the theory is shown by applying it to other works.

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In this paper, the restitution characteristics of golf balls colliding with thin plates, which are the models of club-heads, are described by the results of computer simulation based on a finite element (FE) method and also of an experiment. FE models for a golf ball and plates were constructed by hexahedral solid elements. The material properties of ball was determined as a linear visco-elastic three-element model. On the other hand, circular plates of titanium were thought as a linear elastic body. The impact simulation between the ball model and the target models was conducted by an FE code ABAQUS. The results suggest that the coefficient of restitution tends to be higher at any impact velocity as the thickness of circular plates goes thinner. And the reason of the above was concluded as follows. In case of the collision with a thin target, the target deforms more than with a thick target, and therefore, the ball does not deform so much as in case of collision with a thick target. Therefore dissipation of energy decreases and resilient energy increases. And eventually the coefficient of restitution increases.

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The development of ski goods like a carving ski is increasingly remarkable these days. In this study, we propose the new technique to evaluate the performance of ski goods using biomechanical method. In order to analyze the kinetics of skiing, the motion of a skier's body in the skiing turn has been measured by magnetic position sensors. Reaction forces from the snow surface to the skier have been measured using 6 axis force sensors embedded in the bottom of ski boots. Joint moments of a skier have been calculated from these measured data. Then, we have estimated the energy consumption of the muscles based on the muscle-skeletal model. The experimental results show that characteristics of the ski turn can be evaluated through the activity of the muscles. Our evaluation method will be useful not only for developing ski goods for bio-analysis in sports.

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The transmission gear noise of passenger car becomes usually of problem during cruising condition, i. e. under light loading condition. Three dimensional tooth flank form must therefore be optimized in designing to satisfy not only strength reliability under the maximum loading, but also low vibrational characteristics under the light loading. For designing tooth flank forms to meet those requirements, it should also be taken into consideration that the amount of misalignment of gear shafts under the light loading is quite different from that under the maximum loading, because the stiffness of gear support of automotive transmission is considerably low. In this report, the influence of profile and lead form on vibrational excitation under the light loading and that on tooth root stress, Hertz stress and flash temperature under the maximum loading are clarified: There are local optimum conditions, where vibrational excitation is low, as function of combination of the amount of tooth profile modification, of lead crowning, and of lead inclination. In a definite local optimum condition, the tooth flank form that brings the minimum average rotational displacement between driving and driven gears makes vibrational excitation minimum. The range of the amount of lead inclination that satisfies the requirements for load carrying capacity and vibrational limit becomes smaller with increasing the amount of profile modification, if transverse geometrical contact ratio and overlap ratio are both over 1. The fundamentals for designing the optimum tooth flank form in terms of both vibration and load carrying capacity are shown.

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The alignment condition of automotive gears changes considerably during operation due to the deformation of shafts, bearings, and gear box by transmitting load. Under such condition, the gears are requested to satisfy not only reliability in strength and durability under the maximum loading, but also low vibrational characteristics under light loading at cruising of the car. In the previous report, the fundamental method for optimization of 3 dimensional tooth flank form in terms of both vibration and load carrying capacity for such gears was proposed. Gears of high total contact ratio have although multiple local optimum solutions in the design of tooth flank form and it is therefore needed to choose the comprehensively optimum tooth flank form. In this report, the influence of the choice of different local optimum solution in different vibrational excitation valley and the influence of different vibrational criterion at the optimizing procedure on the low vibrational performance of the optimized gears are investigated. The practical design algorithm for the optimum tooth flank form of a gear set in terms of both vibration and load carrying capacity is then proposed and its result is evaluated by the field experience.

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An entirely new model for estimating the entrained air film thickness between the roller and transporting web (web spacing) is presented for permeable and impermeable webs. Based on the large number of simultaneous, numerical solutions for Reynolds equation and web equilibrium equation, the closed-form formula for the air film thickness, which considers the effects of air leakage from web edges and air diffusions due to the permeability of web, is obtained. On the other hand, the variation of air film thickness with roller velocity is measured for three types of webs with different permabilities; PET (polyethylene terephthalate), coated paper and newsprint. The effects of web permeability, web width and web tension on the air film thickness are examined theoretically and experimentally for a wide range of roller velocity. Reasonable agreements are seen in both quantities and qualities between the calculated results and measured results, and an applicability of the formula to the design studies on the webroller interface problems is verified experimentally.

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In this second paper, the friction characteristics between roller and thin flexible web with different permeabilities is studied theoretically and experimentally. At first step, the standard test is carried out for three kinds of webs, PET (polyethylene terephthalate), coated paper and newsprint, for better understanding the friction characteristics between roller and web. Then, two types of power low model for the averaged contact pressure due to asperities of web and roller surfaces is presented, in which the unknown parameters involved in the models are determined by the inverse analysis to the standard test results of friction coefficient. Combining the contact pressure models developed here with the closed-form formula for air film thickness derived in the first paper, the prediction method of friction coefficient between web and roller is formulated. The air film thickness and friction coefficient are measured by changing the web width for three kinds of webs, and good agreements are obtained between the measured results and the predicted results. Moreover, based on these results, the effects of many design parameters on the friction characteristics are clarified.

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Effects of stiffness of sliding part end between piston and cylinder on the friction characteristics have been investigated experimentally for rotating-swash plate type piston pump and motor. The friction forces were measured by means of Piezo-type load washers under several stiffness of the sliding part end and forcing the piston to rotate. Since the oil whirl phenomena may occur on the piston for certain working conditions, the friction forces were evaluated during two rotations of the swash plate. The friction losses were estimated on the basis of the experimental results. It was clarified that the maximum friction forces and the mean friction losses decreased markedly with decreasing the stiffness, and that the maximum friction forces were almost independent of supply pressure, rotational speed of the swash plate and overhang ratio (bearing width) with low stiffness of the sliding part end.

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The behavior of a tilting-pad thrust bearing is affected by the deformation of its pad and runner. The heat and pressure of the oil film between these parts induce their deformation. Because the heat conduction is a transient phenomenon, the deformation is also transient. Accordingly, the deformation of the pad and runner when the rotor accelerates were calculated under transient thermal conditions. Two different acceleration conditions were assumed. That is, when the rotation acceleration is low, the amount of deformation is large. This deformation makes the pad tilt considerably, so the oil film is thicker at the leading edge than at the trailing edge, while the oil film thickness decreases at the radial center of the trailing edge. On the contrary, when the rotation acceleration is high, the deformation is small, so the pad only tilts slightly, and the film thickness at the trailing edge only decreases a little.

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The Elrod's cavitation algorithm was modified to include the effect of density in full film zone and applied to the mass conserving elastohydrodynamic lubrication, EHL, theory of a con-rod big-end bearing. After that, the calculation method of mass conserving EHL with a simple model of an oil passage was proposed. The mass conserving EHL theories with and without oil passage are compared to discuss the feature of the lubrication characteristics and oil flow rate under the dynamic load of an engine.

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In the 1st report, the Elrod's cavitation algorithm was modified and applied to the mass conserving elastohydrodynamic lubrication, EHL, of a con-rod bearing with a simple model of an oil passage. In this report, the modified Elrod's cavitation algorithm and the mass conserving EHL with oil passage were compared with the conventional method with the Murty's algorithm. The Elrod's cavitation algorithm modified in the 1st report was also compared with that of original one and that modified by Vijayaraghavan and Keith to clarify the effect of density in full film zone. The mass conserving EHLs with and without oil passage were applied to a con-rod bearing with practical clearance shape under full load operating conditions of an engine to clarify the effect of oil passage.

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This paper presents experimental results of the performance of an electrostatic liquid filter model that utilizes an a. c. electric field to make minute contaminant particles be coagulated. The filter model consists of the coagulating cell for coagulating the particles and the collector for capturing coagulated partieles. The effects of the electric field strengths in the coagulating cell and the collector and of the flow velocity are investigated. The effects of the type of electric field, a. c. or d. c., in the collector, the collector mesh size and of the zeta potential of particles are investigated as well. It is shown that the introduction of the coagulating cell to the upstream of the collector enhances the filter performance to a great degree. Useful data to develop a high-performance electrostatic liquid filter are obtained.

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The diffusion process of N₂, O₂ and CO₂ into VG10 machine oil had previously been observed in such a way as measuring the pressure change of gas confined to a constant volume with the oil. Although the measured pressure changes of N₂ and O₂ had been properly predicted by the diffusion theory, it had not been the case with CO₂. With suspicion that the dependency of a diffusion coefficient on the pressure could have influenced the results for CO₂, which exhibits a much larger pressure change in the course of diffusion than N₂ and O₂, the diffusion process was otherwise observed in the present study under a constant pressure, using laser heterodyne interferometry. The diffusion of CO₂ did not agree with its theoretical prediction again, which gave birth to an idea that a convective flow might occur in the oil by the density gradient produced by gas diffusion. Then Mach-Zehnder interferometry was introduced to observe gas-oil diffusion, proving natural convection did happen some time after the diffusion started. The diffusion process of CO₂ before the occurrence of natural convection agreed well with the theoretical prediction, giving reliable values of its diffusion coefficient.

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In this study, a novel peristaltic micro pump using bimorph type PZT elements is proposed. The pumping of liquid is realized by active and peristaltic motion of channel formed with metal film. The motion is controlled with controlling driving voltage of 5 bimorph-type PZT elements that are laid on the metal film. In this paper, the peristaltic micro pump (20 mm×20 mm×2 mm) is fabricated to verify the pumping principle and to examine the characteristics. Intermittent sinusoid driving method for PZT element is proposed to advance the pumping characteristics. The maximum output flow rate of 250 mm³/min is obtained and the maximum load pressure of 3.1 kPa is obtained.

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This paper deals with improvement of the surface roughness for end milling using the cutting edge with a high-accurate flank surface. In usual end milling, it is very difficult to machining a high-accurate surface even if finishing conditions are used, because of the surface machined is copied by the roughness curve of flank surface of a cutting edge. Then it is investigated that the surface roughness of machined surrace in axial direction is improved by high-accurate cutting edges. The main results are as followings. (1) Maximum hight of roughness curve of machined surface in axial direction is almost 10 times as large as that in feed direction. (2) The roughness curve of flank surface of cutting edge was copied on that of machined surface, and the degree of transference is diffined by the mean of the absolute value of defferences of both roughness curves. (3) The maximum hight of roughness curve of a flank surface decreases from 1.71 μm to 0.53 μm of which surface is finished by a diamond wheel. (4) The maximum hight of roughness curve of machined surface decreases drastically from 2.53 μm to 0.58 μm using the above high-accurate cutting edge.

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This research proposes computational models for concurrent design process of large complicated systems as the formal fundamentals for the development of agent-based distributed design support systems. In this first report, we assume that an artifact is modeled with a set of lumped mass systems and that the number of variables is fairly huge to facilitate the discussion. Under these assumptions, the design phases, the types of design knowledge, and their characteristics such as granularity levels, operational cost, fedility, dominatedness, etc. are formally discussed. Furthermore, the design model is primarily decomposed into the global model and domain models, and the horizontal and vertical decomposition of a design process are formulated. Following such decomposition structure, the conception of goal cascading is proposed as a model of coordination structure among the divided design tasks. The goal means the play on an intermediate variable shared among distributed tasks. The discussion deducts three types of coordination: inter, global and inner ones. These understandings are expanded to operational models and a computer-aided design support system in the succeeding papers respectively.

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This research proposes computational models for concurrent design process of large complicated systems toward the development of agent-based distributed design support systems. In this second report, we mathematically formulate the partial design problem of each divided task in the distributed design process under the concepts introduced in the first report. Following them, the backward-chaining operation for refining a tentative design solution is modeled as an optimization problem. Its form belongs to a style of goal programming, since the goals, each of which is the play of an intermediate variable among divided tasks, are defined with a set of regions and domains. The associated mathematical programming method is configured by combining linear approximation, monotonicity analysis and active set strategy to support designer's decision making. The issues on design process management over such optimization-based support are further discussed. Finally, the coordinative design process among divided tasks is briefly demonstrated in an application to preliminary aircraft design.

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This paper discusses product variety design under the viewpoint of design optimization paradigm. Product variety design means the simultaneous design of multiple products toward higher optimality beyond ordinary design methods for a single product. It is expected to be an excellent manufacturing strategy, since design optimization basis is expanded. The paper first shows the possibilities and difficulties of design optimization for multiple products under fixed product architecture. Such optimization demands to determine the contents of modules and their combinations under modular architecture. This indicates that product variety optimization includes three classes of optimization problems, attribute assignment, module combination and simultaneous design of both. The paper defines generic framework on the optimality as the prerequisite for developing optimization techniques for respective classes. Then, stretch-based aircraft design deployment, which is an example of the first class, is explored by means of enumeration and successive quadratic programming, after developing the mathematical model for the evaluation of total profit of a manufacturer through the entire production of all units of different models. Its numerical result demonstrates the necessity and effectiveness of optimization paradigm in product variety design.

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This research discusses and develops the optimization methodologies for product variety design, which means the challenge to simultaneously design multiple products. Following the definition of three classes of optimization problem in the first report, this paper develops an optimization methodology for module combination under predefined module candidates for multiple products, which is the second class of product variety optimization. The situation of this design problem is widely recognized as commonalization in industrial practices. In this paper, by investigating the mapping structure among customer's, functional, and manufacturing viewpoints, module commonalization is recognized as module diversion, and the feasible conditions for diversion is modeled as diversion feasibility, diversion simultaneity, and capacity constraints. This leads the optimization formulation as a 0-1 integer programming problem in a systematically abstract form. Based on the pivot structure among 0-1 variables, an optimization technique is configured based on the simulated annealing technique. Finally it is applied to the simultaneous design problem of electronic circuits for television sets in order to ascertain the validity and effectiveness of the proposed modeling and optimization methodology.

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Primarily, the delivery of multiple kinds of products was done separated. However, as the consumers' needs had diversified, the distribution system also increased. This led to increasing the number of trucks and multiple trips to the same store. Because of enlarging the distribution system total cost increased. To address this problem, summarized delivery, mixing the load of deliver products to one store, is introduced. On the contrary, a realistic approach does not exist. In this paper, we utilized two new neighborhoods, and suggest a method which focuses on a feasible inventory term that would influence delivery efficiency.

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We are developing the disassembling method considering the elementary composition ratio. However, the elementary composition ratio of any products and parts is not indicated, so that these information are not used in the disassembling system. Therefore, we proposed the estimation method of element composition of part by the X-ray fluorescence analysis equipment. (1) The elementary composition ratio of material is estimated based on the image measured by the X-ray fluorescence analysis equipment and image processing. (2) The elementary composition of basic component part (an electronic condenser, an integrated circuit and so on) is stored to the parts database in order to estimate the disassembling product. (3) All basic component part in the product are specified by image processing technique, and its elementary composition are estimated roughly based on its size and elementary composition by using the parts database.

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This paper proposes an approach to optimal generation of cam curves. In the approach, cam curve is described with a uniform B-spline curve and then the values of B-spline control points are optimized with the Complex Method according to the design purpose. The algorithm is simple and the programming is easy since it only needs to compute the performance index value but require no gradient of the index in optimization calculation. Several examples of cam curve generation are also shown together with a performance comparison between the obtained curves and those applied in engineering practice, in order to illustrate the effectiveness of the approach.

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