Computer Aided Engineering (CAE) including the topology optimization technique has been successfully used in many mechanical industries such as automotive industries. However, most mechanical designers, in fact, cannot utilize CAE applications by themselves because of the sophisticated operations and a huge amount of time for the analysis. Recently, the concept of a new CAE, First Order Analysis (FOA), has been proposed in order to overcome these problems. In this paper, we present the topology optimization method using beam elements corresponding to the concept of FOA. First, the mutual stiffness is defined using a mutual energy concept. Next, a multi objective optimization problem to deal with the multiple loading problem is formulated, and the optimization procedure is developed based on the ground structure approach and sequential convex programming. Finally, some examples are provided to confirm the optimization method proposed here.

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The stent implantation is a low invasive and effective method to treat the coronary artery blockage. The problem of stenting is restenosis because of initimal thickening, which occurs in 20%. Restenosis rate is related to the radial stiffness and bending stiffness of a stent. In order to prevent the recurrences of coronary stenosis, it is necessary to investigate the mechanical properties of a stent. However, test method about these properties is little known. The purpose of this study is to propose a method to estimate the flexibility of a stent. To achieve the aim, we developed a test apparatus by use of four points bending and measured the bending stiffness of 4 stent structures. The result showed that the link stent structure was more flexible than the tube one. Considering a link configuration, S shaped link stent structure was flexible. The flexible stent deformed smoothly by bending moment. On the other hand, the low flexible stents deformed with buckling. This feature was clear in compressive side when stent was bent.

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When designing rotor systems, development costs and the number of trial production runs must be minimised. To do so, the optimum structure must be found by combining CAE optimisation tools during the initial stages of development. We propose a low-response magnification design method for process compressor rotor systems supported by damper bearings. The effectiveness of this method is demonstrated by experiment. The main elements of our system are (1) a variance analysis of the contribution rate of design variables and mutual actions, (2) an assignment of the design variables to the orthogonal array, (3) a rational parameter survey of this array, and (4) an understanding of solution space from multiple points of view gained by using an approximation method for a response surface model.

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Viscoelastic damping materials with a constraining layer have excellent damping properties, but they have a weighty drawback that many works, such as preliminary treatment of adhesive surfaces and hold of viscoelastic damping materials till adhesive is completely stiffened, are required. To overcome this drawback, magnetic rubber dampers with a constraining layer (MRDC), which are composed of two layers-a magnetic rubber layer and a constraining steel layer-have been developed. They are easy to be fixed onto steel objects due to the attractive force of magnetic rubber layer. The damping property of MRDC is substantially caused by the friction loss which arises between the magnetic rubber layer and the steel object. The equation of loss factor of a beam with a sheet of MRDC is derived by taking the friction loss into account to analyze the flexural vibration of the beam.

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In a previous study, we developed a new transfer matrix method for analyzing the harmonic and subharmonic oscillations of a nonlinear multi-degree-of-freedom system. In this study, we generalize this method so that it can analyze such oscillations as the combination resonance, which are composed of several components with unknown frequencies. As a numerical example, the combination resonance of three-degree-of-freedom system with nonlinear spring property is analyzed. The stability determination is also conducted in a similar manner to transfer matrix method. By comparing the results of the method with those of numerical integration of the equation of motion, the validity of the proposed method is confirmed.

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The influence of a delamination on the natural vibration characteristics of circular laminated plates has been investigated. Free vibration of the clamped plate with a disk-shaped delamination of arbitary size and thickness-wise location is analyzed on the basis of the theory of a small deflection of plates. Basic assumption is that the delaminated layers are contacting one another, and the distribution of mutual contact pressure is also analyzed. The experimental results are corroborated with simplified plate theory models for natural frequencies.

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The transient behavior of a bowed string from a Helmholtz motion to a double slip motion was observed using a simple apparatus consisting of nylon lines which served as a bow, and a string. As the bow speed increases, the motion transits from a Helmholtz motion to a double slip motion. Two Helmholtzian waves with different amplitudes and phases occur during the transition from a Helmholtz motion to a perfect double slip motion. This behavior is examined using numerical simulations, which provide good agreement with the experiments.

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In recent years, the level of dynamic quality of one box-car required to be the same as that of a passenger car. To meet this requirement, various vibration problems have to be examined. In this paper, among them the problem of mirror image vibrations is considered. As compared with a passenger car, the outer mirror of a one-box-car is larger is shape and thinner in depth, and is attached at more forward position. Due to these, mirror image vibrations are severer in a one-box-car than in a passenger car. To find a way to reduce the vibrations, we first studied the characters of the mirror vibrations by modal analysis. Then we studied the velocity distribution of wind around the mirror by PIV (Particle Image Velocimetry) technique. Based on these studies, we proposed a better form of the mirror, which reduced the mirror image vibrations.

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The vibration cutting has attracted attention as a precision machining method for the difficult to-cut materials, including titanium, nickel, ceramics and so on. However, there are some cutting conditions where the vibration cutting cannot keep the worked surface roughness at a constant value. Therefore, it is necessary to make the system which keeps watch on the state of workpiece and estimates its surface quality during the vibration cutting. In this paper, we propose a new simplified method for the estimation of the workpiece roundness in the vibration cutting system. Our method uses time-series data of the workpiece displacement measured by an eddy current sensor. We carry out experiments with varying the cutting speed, and show that the estimated roundnesses calculated by our method are in good agreement with measured ones when the vibration cutting system is in good cutting condition. Even if the chatter vibration arises in the system or the tool edge is worn, our method is able to give good estimated values.

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This paper proposes a new method how to construct the reduced order model of mechanical system with strong gyroscopic effect used for control system design of closed loop system. It is very difficult to construct a reduced order model for control system design of mechanical system with gyroscopic effect because gyroscopic matrix is anti symmetric matrix. So the reduced order model of mechanical system without gyroscopic effect in used to construct controller and the controller used in closed loop system with gyroscopic effect is desired to get good control performance. But sometimes good control performance is not able to obtain for mechanical system with strong gyroscopic effect. So, in this paper cholesky decomposition has been used to construct the reduced order model for control. In order to demonstrate the validity of this method, the controlled model and sliding mode control of a 10 MWh class energy storage flywheel system are given in this paper. This flywheel system is the outer rotor that consists of a four spokes rib, CFRP flywheel, superconducting magnetic bearing and active magnetic bearings. In order to construct the controlled model of system, the conceptual design and vibration analysis using ANSYS had been done. Then the one dimensional FEM model and reduced order FEM model with gyroscopic effect used for control are designed. To verify the stability of closed loop system, the sliding model controller with low-pass filter are designed and closed loop simulation is done. From simulation, it seems the proposed method is useful for control system design taking into account a strong gyroscopic effect.

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This paper proposes a design method for vibration isolation control of a semi active suspension for automobiles. By using nonlinear functions we formulate the linear-parameter-varying system taking account of mechanical constraints such as valve stroke of the semi-active damper and the damping coefficient restriction. The gain-scheduled controller based on the linear matrix inequalities is obtained so that the closed-loop system may be stable and have good performance even if saturation of the valve stroke occurs. By simulations it is verified that the semi-active damper system designed is effective in comparison with either a passive damper or a conventional switching law based on H_∞ control.

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This paper presents a design scheme which is constructed with a Model Reference Adaptive Control (MRAC) and a multi-rate neural network (NN) for the pneumatic servo system. As the NN has excellent nonlinear mapping and learning capabilities, this method has accomplished excellent control performance. However, structure of the proposed design scheme is so complex that calculating-time of weights in the NN exceeds one sampling time. To overcome this problem, we introduced multi-rate NN in which update time of weights is selected as multiple of the sampling time. The effectiveness of the proposed design scheme is confirmed by experiments using the existent pneumatic servo system.

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This paper proposes a precise tracking control method for a rigid body motion system by obtaining a model of the motion system on line and implementing H_∞ control to improve tracking performance. In order to execute precise tracking control, nonlinearities in the motion system such as variation of inertia, Corioli's force, electromagnetic driving force and gravity should be modeled in the motion control system. Hence, the method of obtaining the models of the motion system is introduced in this study. However, after the models are obtained, there exist modeling errors and unmodeled forces. Therefore, H_∞ control method is introduced to attenuate disturbances due to modeling errors and unmodeled forces. In this paper, effectiveness of the proposed motion control method by a simulation and an experiment of tracking desired trajectory in a direct drive 2-degree-of-freedom link motion system.

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A new decoupled track-seeking controller design is described for dual-stage servo systems of magnetic disk drives. The controller is applied to the dual-stage system with a push-pull piezoelectric (PZT) microactuator and enables high-speed one-track seeking. The one-track seeking controller was designed in three steps : 1) A VCM feedforward controller was designed to prevent overshoot in response of VCM actuator. 2) A feedforward loop was designed from the VCM reference signal to the PZT actuator in order to decouple the dual-stage actuator system. 3) A feedforward controller was designed for the PZT actuator such that an output PES (position error signal) only follows a PES reference signal. The robustness of the seeking controller for both gain variations and PZT hysteresis is analyzed by using simulations. Simulations and experiments show that the proposed dual-stage track-seeking controller performs better than the conventional single VCM servo and achieves 0.3ms one-track seeking time.

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In this study, a new PWM method using high speed sampling strategy based on the presupposition of using a quick driving circuit which can rapidly switching the high speed solenoid valve as quickly as possible is proposed to improve the response precision and to reduce undesirable on-off characteristic in steady state of electro hydraulic servo system controlled by high speed solenoid valve. In addition, the decision method for PWM parameters such as gain, basic period of PWM and sampling time is cleared up. The experimental result shows that it is possible to achieve precise and quiet control without occurrence of limit cycle and without necessary of designing wide range dead band.

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A novel spacing measurement using the Michelson laser interferometry was enhanced to permit a direct measurement of head-disk spacing without necessity of calibration. This method utilizes the phase comparison of two kinds of interference fringe patterns formed over the slider lubricating surface and the inner back surface of a glass disk. To increase resolution and reproducibility, three principal techniques were newly introduced; an optical system mounting a hi-definition CCD camera, a wobbling technique to capture fringe image, and powerful ridgeline extraction from the fringe pattern. These techniques were confirmed to improve the reproducibility to less than a standard deviation of 1nm. To derive the absolute spacing value from the observed value, pseudo phase shift, which is generated by superimpose of the light beam reflected on the glass inner surface, must be cancelled. For this purpose, the phase shift was calculated under the multiple beam interference considering phase delay on the conductive slider material, and thus procedure for the cancellation was established. Finally, the measured spacing and the calculated spacing were found to be in good accordance, indicating the present method to be applicable to the practical usage.

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Much effort on modeling, identification and tuning of control parameters are required to stabilize magnetic levitation systems because of their negative stiffness and nonlinearity. The purpose of this study is to propose a practical control which achieves the stability and compensates the nonlinearity without trial and error. In this paper, first, a controller consisting of a balanced current compensator and PD elements is introduced. The balanced current compensator produces a current to counterbalance the gravity of a controlled object. Then a method for determining a function of the balanced current and parameters of the PD elements by simple preliminary experiments are proposed. The control parameters are automatically designed to achieve the maximum speed of the system. Finally the stable levitation and fast positioning of the object are realized in an experimental one degree of freedom system.

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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. We have been analyzing and investigating the relationship between morphology and intelligence acquired through the difference of tasks and the characteristic differences of functions emerged from the balance between them. In this paper, a simulation of a task in which the robot had to maintain a certain distance from an object is executed. As robotic morphology, we use visual sensors changed its position through evolution by genetic programming : GP and robotic intelligence described as a decision tree is also evolved by GP. The results clarified the importance of balance between morphology and intelligence and showed effective functions emerged as the result of such balance.

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This paper introduces a brachiation type locomotion robot with 13D. O. F. and proposes a learning algorithm for a hierarchical behavior based controller. The brachiation type locomotion robot "Brachiator III" has similar mechanism and dimensions to a long-armed ape, which can perform dexterous motion using a redundant mechanism. A hierarchical behavior-based approach is useful to design a controller for a dynamical motion with multi-degree of freedoms. However some difficulties remain in adaptation phase when the objective behavior or environment conditions are changed. We propose a novel algorithm to improve a global behavior against these changes using Newton Raphson method. This algorithm measures the effects of local behavior controllers to the global behavior as a gradient information, and changes the amplitude of each behavior controller in fewer trials. This learning algorithm is applied to the brachiation robot control.

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This paper proposes an adaptation algorithm of a regrasping strategy for rectangular objects with different dimensions. We had already derived an generation algorithm for regrasping strategy by using evolutionary programming, which is a kind of evolutionary optimization method. Such a regrasping strategy was not applicable to an object with different dimensions. In order to expand the applicable size, we propose three adaptation algorithms and their hybrid algorithms for different sized-object in this paper. We show its effectiveness by numerical simulations and experiments.

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In general, the master slave system which can display both position and force information to an operator is not used for earth to space teleoperation, since the system becomes unstable due to the communication time delay problems. Therefore, a joystick has been a popular master device in the space teleoperation until now. However, the master slave approach can be applied to a model-based space teleoperation employing the virtual reality techniques. In our previous works, a model-based space teleoperation system which has robustness against modeling errors has been demonstrated using a real space system Engineering Test Satellite VII (ETS-VII). This approach has lead to a new possibility of the master slave control in the space teleoperation. In this paper, the operability of the master slave control is compared with a force joystic control from different angles using the real space system ETS VII.

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Many optimization methods and practical softwares have been developing for many years and most of them are very effective, especially to solve practical problems. But, non linearity of objective functions and constraint functions, which have frequently seen in practical problems, has caused a difficult situation for optimization. This difficulty mainly lies in the existence of several local optimum solutions. In this study, we have proposed a new global optimization methodology that provides an information exchange mechanism in the nearest neighbour method. We have developed a simple software system, which treated each design point in optimization as an agent. Many agents can search the optima simultaneously exchanging the their information. We have defined two roles of the agents. Local search agents have roles on searching local optima by an existing method like the steepest decent method and so on. Stochastic search agents investigate the design space by making use of the information from other agents. Through simple and several structural optimization problems, we have confirmed the advantages of this method.

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An axle supporting system which satisfy both steering and stability was proposed previously by one of the authors. To utilize the benefit of the proposed system fully, it is needed to decide the suitable parameter values under theoretical ground. This paper describes a parameter design method for the axle supporting system step by step, considering the maximum operation speed, the maximum curve radius, and so on. Here, the parameter values are restricted to be within the possible range for present railway vehicles. To show the effect of the parametrized axle supporting system, numerical simulation is performed for two cases, one is for high-speed inter-city train and the other is for low-speed mass transit one. Calculation results show that the curving performance, such as attack angle, lateral force and wear index, is improved with the parametrized system, maintaining the adequate stability, in both examined cases.

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In this study, a simple method of numerical analysis to obtain particularly the local characteristics of the surfaces of machine elements processed by straight lined tools is presented. In addition, as examples of the application of this method, the measurement, the error analysis and the measured results using a three-dimensional measuring machine are reported for the tooth surface of a Hindley hourglass worm, Furthermore, we also report that the local characteristics of the two tooth surfaces obtained by our numerical analysis explain the analytical and experimental results of the tooth contact fairly well.

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The assembly interference of the spiral bevel gear of Klingelnberg cyclopalloid system is analyzed on the basis of gear kinematics. There is a case that a pinion cannot be assembled because of an interference of spiral teeth, when the pinion must be pushed in the direction of its axis to assemble in gear box in which a mating gear is assembled previously. This interference shall be designated as 'assembly interference' in this study. The meshing states of pinion outside and gear inside convex tooth surface, together with backlash, determine that the assembly interference occurs or dose not occur. The state of tooth surface is formulated in connection with the pinion rotation angle. And the assembly interference is axamined with the test gears made as a trial. From the examinations, the validity and usefulness of this analysis are confirmed.

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This paper presents a study on the load bearing capacity of super-carburized gears. Test gears and rollers of MAC14 and SCM415 steel were super-carburized or eutectoid-carburized under different carburizing conditions. The bending fatigue and contact fatigue tests were carried out for these test specimens. The effects of case depths on the bending fatigue strength of gears and contact fatigue strength of rollers were determined. The bending fatigue strength of super-carburized gear was found to be almost equal to that of eutectoid-carburized gears. The contact fatigue strength of super-carburized roller becomes larger with an increase of case depth and is larger than that of eutectoid-carburized rollers in the case of larger case depth. The surface failure modes for super-and eutectoid-carburized rollers were spalling. The load bearing capacity of super-and eutectoid-carburized gears was found to become larger by shotpeening.

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Next generation LEO (Low Earth Orbit) System (NeLS) that would provide a global multimedia mobile satellite service for handheld user terminals has been studied by the Next-generation LEO System Research Center. The system needs large active phased array antennas on board the satellites. Therefore, it is essential to develop a two-dimensional deployable antenna panel. In this paper, a deployment sequence for active phased array antenna is proposed. The sequence will be able to provide a stiff and accurate antenna. Also, new types of hinge and latch mechanism are proposed for the antenna. Each hinge is located at reverse side of the panels after deployment, there is neither gap between panels. The newly developed latch pulls the shaft into the holder with very low torque, after the shaft is latched incomplete. The effectiveness of the proposed hinge and latch mechanism were confirmed by experiments. Next, we will develop the two-dimensional deployable panel for active phased array antenna by the proposed sequence with the proposed hinge and latch.

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Because pneumatic rubber muscles are light in weight and flexible, they are expected to be applied to driving elements of mechanical systems such as service robots which often contact with human. In the pneumatic rubber muscle, tensile force/displacement is generated according to applied pressure to it, and the relationship between input pressure and output force/displacement is very nonlinear including hysteresis. Since the muscle generates only tensile force and its motion range is quite limited, their considerations in mechanism design are important. In the present paper, the control method based on the experimentally identified relationships between input and output of mechanial systems proposed by the authors has been applied to the motion control of in-parallel actuated mechanisms with the muscles. The transmission index for in-parallel wire driven mechanisms has been applied to the design of such mechanisms. The effectiveness of these methods has been investigated experimentally.

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The structure of a mechanical torque limiter for a space manipulator, which is used for tightening and loosening bolts in space, was studied geometrically in the previous report. Following results of that report, we produced a mechanical torque limiter experimentally, and carried out a series of tests to estimate its performance and reliability. The results of the tests are as follows. 1) The performance of the mechanical torque limiter is good enough for a space manipulator. 2) The reliability of the torque limiter is four times better than the specification requirement.

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In a previous paper, we developed a new method of measuring a distribution of real contact area between two solid surfaces using PET film. Tiny protuberances on the PET film were produced to reduce its friction. In the measurement, these protuberances could not be distinguished from the real contact area. Thus the calibration was needed to remove the effect of the protuberances before the experiments. In this paper, we produced four kinds of polymer films without the protuberances on their surfaces. The real contact area was measured with those polymer films. We discussed the effect of the mechanical properties of those polymer films on the measurement. It was found that the elongation property of the polymer was important to this kind of measuring method.

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When the ceramic bearing is used under the high temperature environment, the problem occurs. An interference changes because the coefficient of thermal expansion is greatly different between the steel and the ceramic. It is thought that this causes the adverse effect for a load carrying capacity of the ceramic bearing. In this paper, we have applied the shrink fitter to an assembly of the ceramic bearing to prevent the change in the interference. The outer races were broken at the load of 4410N when the shrink fitter was not used. With the shrink fitter the load carrying capacity was 8330N. Moreover, the stresses acting in the outer race of the ceramic bearing, due to the space between the outer race and the bearing, were analyzed by FEM.

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To clarify the seizure resistance of radical nitrided bearing steel SUJ2, a four-ball test was carried out under dip-feed lubrication using a Soda four-ball machine. Four kinds of the combination of the ball pair were tested. The symbol N-N indicates the ball pair without nitrided, the symbol R-N indicates the ball pair in which only stationary ball was nitrided, the symbol N-R indicates the ball pair in which only rotatory ball was nitrided and the symbol R-R indicates the ball pair in which both stationary and rotatory ball were nitrided. From the test, the following results were obtained. (1) At the load stage before seizure, the value of coefficient of friction μ with ball pair N-R was the smallest of all ball pairs, and was about 0.07. (2) The order of the seizure resistance of the ball pairs was N-R>R-R>R-N>N-N. The seizure resistance for ball pair R-R was about 2.6 times as high as that for ball pair N-N, and a significant effect of the heat treatment due to radical nitriding on increasing the seizure resistance of bearing steel with a small amount of Cr content was recognized. (3) With ball pairs N-N and R-R, the critical surface temperature θ_cr at the risk for seizure was about 369∿376°C. The values of θ_cr with ball pairs R-N and N-R were about 495 and 302°C, respectively.

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For effective utilization of waste wood, binderless board and cup were made of lumber chip by compressive shaping. Sugi shavings were used as lumber chip. Lumber chips were hardened by compressed in the die and heated in a furnace for a few minutes and cooled at room temperature. Binderless board could be produced when specific gravity was more than 0.4. Modulus of rapture was most high when heating temperature was 180C and heating time was 60min, and the maximum value was about 6N/(mm)² when specific gravity was 0.9. Conformability to the die inscribed triangular and rectangle grooves became good as forming pressure became large, but limit of conformability existed. Conforming height was most high when groove angle was 30 or 45. Binderless cup without crack could be produced when convex die was under the chip and the tip of convex die was hemisphere. Load carrying capacity of the cup was 2∿7.5kN.

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Low temperature annealing of helical compression spring using phosphor bronze fine wire is investigated, aiming short time residual stress relieving. In the process of coil spring, it is necessary to relieve the residual stress caused during wire deformation. But, the time for its heat treatment time is very long, for example, 10 minutes to 2 hours. To change this condition, residual stress relieving rate is formulated under the assumption that this stress relieving process is equal to stress relaxation in creep. This is because the both are caused by recovery of metal crystal before recrystallization, explained by dislocation theory. Next, the constants of formula are determined through the experiments, measuring isothermal change of the uniform tensile stress. Utilizing the formula, the short time condition for annealing is found. As the result, in line coiling, annealing, and assembling is made possible.

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A novel ultrasonic vibration polishing method was developed by introducing an assistant ferrule between the multi fiber connector and the ultrasonic vibrator, which enabled the ferrule endface to be processed exclusively without contact with fiber endface. By this method, the desired fiber protrusions of all the fibers in multi fiber connector were obtained efficiently in a short time so that good optical characteristics were achieved. Insertion loss difference of single mode 12 fiber connector with and without index-matching material was less than 0.04dB, and optical characteristics of 12 fiber connector without index matching material remained stable during the reconnections of 500 cycles. Good and stable physical contact (PC) connection was achieved. Compared with the conventional method, this novel method raises the processing efficiency greatly.

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A large variation in the assembly times is observed among different product types when they are produced by a mixed-model assembly line. The variation reduces production efficiency and may cause a line stoppage. However, the variation of the assembly times can be reduced by installing a bypass line which processes a part of assembly operations of product with relatively longer assembly time. The paper presents that the installation of a bypass line will reduce the total line length of the entire assembly line as well as the variation of the assembly times. An optimization model and its branch and bound algorithm are developed to minimize the total line length. The decision variables are the number of stations for each of main and bypass lines and the product types to be processed at the bypass line. The computational efficiency is discussed through numerical examples.

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Cumulative curve method is useful technique for the production process control and often used in the manufacturing systems. Cumulative curve, which is composed with the input amount of materials and the output amount of completions, shows the physical flow from the start time to the end time of the production. But the cumulative curve is difficult to formulate to the equation. This paper proposes the GM (1, 1) model for the analysis of cumulative curve. It shows methods to clarify the shape and property of several cumulative curves from the theoretical formula of the model, to utilize the parameter a and b of the model as the scale which evaluates the production rate and to predict cumulative curves. The inventory quantity and lead time are also obtained from the theoretical formula, when the value estimated in the GM (1, 1) model is applied to the GM (1, 2) model. In addition, these models are possible to applicate for daily management practice for the prediction equation.

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In a parts recycling system, reusable parts in the collected waste products are employed to produce new products with new parts. Two assembly methods are considered in the parts recycling system. The primary method is random assembly, in which new parts are selected randomly from the entire population and assembled. The remaining method is selective assembly based on the combinatorial optimization method, in which a combination of reusable parts and new parts is optimized so that high quality assembled units are obtained in a lot unit at the maximum assembly rate while dimensions of each part are referred to appropriately. The assembly methods are applied to the parts recycling system where hole parts are combined with shaft parts. In this paper the effectiveness of parts mix, reusable parts and new parts, is clarified in various situations.

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At present, it is important problem to reduce transportation cost for most of corporation. In recently, most of customer have specifying time to be served by transportation companies, and it is important for the companies to keep it. Because both reducing cost and improving quality of services are hoped by many transportation companies. Thus, one of the best ways to keep the time window is better scheduling of trucks. And useless waiting time and running time can be reduced. But these are made difficult by following two things. 1 : Time window of customers. 2 : Limited number of berths. Particularly in case of multi route service, 2 is very important. And it is very difficult to solve VRP under limited number of berths. So how to make schedules including both 1 and 2 is needed very much. But there is no research until now. Moreover by making these, it can be easy to work at depot. For these reasons, in this research I develop how to solve Vehicle Routing Scheduling Problem under Limited Number of Berths.

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This study deals with the development of new hammering tool called "air chipper". Hammering tool is one of typical deburring tools, and air-chipper is conventionally used to perform the deburring work for cast workpieces. Although air-chipper is an effective tool, there are problems of durability and quality since it is driven by compressed air. Excess energy after hammering motion transfers to damper rubber and causes the deterioration of rubber, which leads to the breakage of a chisel holder of air-chipper due to the crash with the stopper. In addition, the difficulty to directly measure the chisel motion causes uncertainty of deburring quality. Thus, the improvement of air-chipper was intended to solve the above problems by introducing an air damper to the air-chipper. It is possible to diagnose the deburring quality by measuring the inner pressure of air damper room. As a result, airchipper installed in a deburring robot system reveals an effective performance in combination with the image processing device.

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Recently, as an electronic and an optical part with high precision are required, high precision machining is done very much. At that time, a 3-dimensional coordinate measuring machine (CMM) are used for measuring. However, as the structures of the CMM and the measured part are influenced by ambient temperature fluctuation, the thermal deformation of those structurs reduce measurement accuracy. Therefore, in this report, a few insensible structure technologies for reducing thermal deformation caused by ambient temperature fluctuation were devised and evaluated. Those technologies consist of local cooling for the measured part, structure of thermal insulation using styrol foam with high density and structure of high thermal inatia using the table with water. It is concluded from the results that the proposed technologies were very effective in order to reduce thermal deformation of the CMM.

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Distributions of fiber orientation and fiber concentration were measured in the flow of a concentrated fiber suspension through a slit channel with a sudden expansion. The suspending fluids are a 200ppm solution of polyacrylamide and a Newtonian fluid. For a concentrated fiber suspension in the polymer solution, the fibers rapidly orient in the direction perpendicular to the flow direction just downstream of the expansion. Moreover, the fiber orientation in the polymer solution has a distribution similar to that in the Newtonian fluid. These sudden changes in orientation at the expansion are due to fiber fiber interaction. For a dilute fiber suspension in the polymer solution, the fiber orientation is greatly different from that in the Newtonian fluid at the expansion and in the downstream region, which is caused by a large elongational viscosity of polymer solution. Therefore, in the concentrated suspension, it was found that fiber fiber interaction strongly affects the distribution of fiber orientation in the expansion flow, while the elongational viscosity has little effect on it. On the other hand, polymers had little effect on the fiber concentration distribution. Thus fiber concentration is caused only by fiber-fiber interaction.

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