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前原 孝章, 中井 幹雄
2003 年 69 巻 679 号 p.
557-564
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper deals with the stability of chaos in forced-dumped nonlinear oscillators using numerical simulations. Invariant manifolds, which present basins of attraction in phase space, provide the differences between "transient chaos" and "steady-state chaos". The presence of a stable periodic motion never assures that observed chaotic motions are transient. Mechanical energy and stability of both stable and unstable periodic motions are computed in order to distinguish their motions. This distinction can explicitly exhibit what kind of motions can coexist with steady-state chaos and how steady state motions depend on initial conditions.
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永井 健一, 鈴木 央, 山口 誉夫, 丸山 真一
2003 年 69 巻 679 号 p.
565-572
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Analytical result is presented on chaotic oscillations of a buckled beam under an axial spring. The beam with a concentrated mass is clamped at both ends. The beam is compressed to the post-buckled configuration by the axial spring. The beam is subjected to periodic lateral acceleration. Introducing a mode shape function to a basic equation, nonlinear ordinary differential equations of multiple-degree-of-freedom system is reduced to by the Galerkin procedure. Changing a stiffness of the axial spring, an internal resonance condition of one to two is selected. First, steady-state resonance responses are calculated by the harmonic balance method. The chaotic responses are obtained by a numerical integration. The chaotic responses are examined by the Poincare projection, the maximum Lyapunov exponent and bifurcation diagrams. The chaos due to the internal resonance is easily generated by a small amplitude of excitation. As the exciting frequency decreased, transition to the chaos from a periodic response needs larger amplitude of excitation. In a lower range of frequency, the chaotic oscillations are mixed with the internal resonance and the dynamic snap buckling. Two modes of vibration contribute to the chaos related to the internal resonance. Number of the modes increases more than three for the chaos involved the dynamic snap buckling.
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塩練 俊一, 永井 正夫
2003 年 69 巻 679 号 p.
573-578
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
In ropeway transport systems, the swing of carriers caused by a lateral wind is an important vibration problem because of transportation safety and ride comfort. This paper deals with a vibrational characteristics of ropeway carrier models which is suspended from two parallel hauling ropes. The bicable ropeway systems are described by a linear system with two degrees of freedom excited by lateral wind. These dynamical models which both with conventional rigid hangers and with new rotative hangers are analyzed theoretically. The semi-active control method is applied to the rotative hangers model, and carried out computer simulation. These results show that the carrier system using rotative hangers with the semi-active control damper are proved to be effective for reducing vibration.
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小林 直樹, 池田 雅夫, 長谷 雅人
2003 年 69 巻 679 号 p.
579-585
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper proposes optimal design of frame structures for vibration transfer suppression. The H
∞ norm of the transfer function from disturbance sources to the output points where vibration should be suppressed, is adopted as the objective function to represent the magnitude of vibration transfer. The design parameters are the cross-sectional areas of frame elements. For minimization of the H
∞ norm under the constraint of the total mass, a gradient method is employed, where the gradient vector is computed numerically from the variation of H
∞ norm for suitable small changes of elements satisfying the mass constraint. An example is presented to demonstrate the effectiveness of the proposed design method.
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江 鐘偉, 竹内 保隆
2003 年 69 巻 679 号 p.
586-593
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This work presents a study on development of a practical and quantitative technique for assessment of the structural health condition by piezoelectric impedance-based technique associated with longitudinal wave propagation method. A truss structure constructed by aluminum beams and piezoelectric patches is investigated experimentally for estimation of the fastening condition of bolts which is supposed to be a kind of infancy damage. The bolt fastening condition is adjusted by torque wrench. In order to estimate the damage condition numerically, three damage indices, impedance peak frequency shift ΔF, peak amplitude ratio δ and quality factor ratio γ, are proposed in this paper. Furthermore, an assessment method is described for estimation of the damage by using these three damage indices. As an example, estimation of fastening torques on the bolt is illustrated. With a plenty of experiment results, the damage indices proposed in this work are validated useful for assessment not only of the looseness of bolts and also for any other structural infancy damage, such as the concentrated stress, small crack and so on.
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江波戸 明彦, 田中 信雄, 永田 寿一, 穂坂 倫佳, 塩山 勉, 中川 篤, 小林 雅彦, 谷村 新
2003 年 69 巻 679 号 p.
594-602
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper considers the minimization of total acoustic power radiated from a large duct opening. The sound field in the large duct opening is not always represented by a harmonic modal function. Therefore, the authors consider that the complex pressure amplitude at any position in duct opening can be regarded as random function, and propose a method employing an active noise control in order to minimize the total acoustic power by designing the duct opening, leading to change the complex pressure amnlitude in the duct opening. The power reducing performance was confirmed by the basis of theoretical estimation.
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森山 裕幸
2003 年 69 巻 679 号 p.
603-610
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper describes the coupling of the vibration of exciting circular end plates and the sound field in a cylindrical enclosure. Assuming that the lateral wall of the cylindrical structure is rigid, a theoretical analysis is carried out for the relative amplitude and the phase difference as to both exciting forces, which influence the coupling of the vibration of the end plates and the sound field. If the vibration modes of both end plates are coincide with the different acoustic modes of the sound field with respect to the circumferential order, the distribution of the sound field has the complex nature of some acoustic modes. The distribution depends on the relative amplitude of both exciting forces. Coupling with the same vibration mode of both end plates, the acoustic modes with the cylindrical length orders are restrained from dominating the odd orders by the exciting forces of the same phase, while the inverse phase makes the even orders restrained.
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吉田 勝俊, 佐藤 啓仁
2003 年 69 巻 679 号 p.
611-617
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The delayed feedback control is applied to stabilize noise-induced chaotic behavior of a Duffing oscillator and a parametrically excited pendulum with noisy harmonic excitations. We first follow the standard pullback procedure to obtain random invariant measures and then intuitively construct Poincare maps of them. Nonchaotic and chaotic sample processes are stabilized in a similar way to the deterministic delayed feedback control. Fractal structures of chaotic random processes are stabilized into point structures.
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吉田 勝俊, 佐藤 啓仁
2003 年 69 巻 679 号 p.
618-623
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The authors propose a new control method for a random synchronization of self-excited systems. The authors find, from a random dynamical point of view, that a self-excited system and its copies subjected to a sample process of noise are precisely synchronized with each other. The control method derived from this principle works well with a van der Pol vibration system and a nonlinear retarded system. The noisy input results in purely random vibrations which are precisely synchronized with each other.
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庄野 崇, 長坂 直, 背戸 一登
2003 年 69 巻 679 号 p.
624-632
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper proposes a new vibration isolation control method for flexible table with multiple modes to be controlled. In the lightweight isolation table, elastic modes appear on the table in lower frequency range. In order to avoid the elastic vibration of the table, it is necessary to control the vibration in addition to isolation. In this study, a reduced-order model expressed by 5 DOF systems for controlling the models is applied. For designing the controller, LQ control theory and double-active control method with feed forward control are used. Effectiveness of vibration isolation and control of the flexible table is verified through numerical simulations and experimental results.
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黒川 賢, 稲垣 照美, 笠井 豊, 宮本 貴範
2003 年 69 巻 679 号 p.
633-638
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The distortion of thermogram, which is caused by the scanning speed and the drawing performance, is one of the most important performance indices of thermograph in addition to the noise equivalent temperature difference and the minimum detectable size. In particular, the distortion of thermogram occurs when taking a thermogram of moving object, if the scanning speed of the thermograph is not so high enough. lt is necessary to evaluate each performance index of thermograph in order to establish the effective and quantitative measurement. lt is also important to clarify the cause of distortion. The distortion of thermogram for medical thermographs has already been standardized in Japanese Industrial Standard (JIS). The standard says that the distortion of thermogram is determined from the ratio of length to breadth in the thermogram of a circular test pattern. 0n the other hand, this paper proposes a new method how to estimate the distortion more precisely than the previous standard.
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山田 祐士
2003 年 69 巻 679 号 p.
639-645
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Pneumatic servo systems contain non-linear elements caused by compressibility of the air, various frictions and so on. And the discrete-time model of the plant usually becomes non-minimum phase caused by above one. Therefore, it is difficult for ordinary linear control methods to accomplish satisfactory control performance in a pneumatic servo system. In this note, we propose a design scheme which combines an adaptive pole-allocation control with a multi-rate type neural network (NN) for the pneumatic servo system. In this design scheme, the role of the NN is to compensate for constructiong a linealized model of the non-linear plant of the electro-pneumatic servo system. 0n the other hand, the role of the adaptive controller is to control above linealized model. As the NN has excellent nonlinear mapping and learning capabilities, this method has accomplished excellent control performance. However, this design scheme whose structure is too complex has a defect that a calculating-time of weights in the NN exceeds one sampling-time. To overcome this problem, we introduced multi-rate type NN 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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小口 俊樹, 村山 昇, 川田 誠一
2003 年 69 巻 679 号 p.
646-653
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The system with feedback loops that pass through computer network is called networked control system (NCS). For the system, this paper proposes a compensator for time-varying time delays, the packet loss and the packet disorder that are caused by the communication network. The proposed scheme consists of the model-based state prediction, an input buffered memory and use of time-stamped data. By applying our proposed method, nonlinear networked control systems are transformed into a linear controllable system with a fixed time-delay at the input. The proposed compensation and control strategy are tested through a control experiment over a physical network.
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橋本 雅文, 川島 洋之, 大場 史憲
2003 年 69 巻 679 号 p.
654-661
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper proposes a multi-model based approach to fault detection and diagnosis of internal sensors in mobile robot for a robust dead reckoning. A scale failure, at which the scale of sensor outputs differs from the normal, is handled as the failure type. The scale factor of the sensors as well as the robot velocity is estimated with single-model based Kalman filters, each of which is based on a model matching to a failure mode of particular sensors. The model-based estimates of the scale factors are compared with each other, and then fault decision is made. The proposed fault detection and identification algorithm is implemented on our skid-steered mobile robot with five internal sensors (four wheel-encoders and a yaw-rate gyro). Fifteen fault modes are modeled to correctly diagnose the failure of any one of the five sensors. Experimental results show the property of the fault detection and identification algorithm.
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深尾 洋一郎, 野波 健蔵
2003 年 69 巻 679 号 p.
662-668
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Two topics about mine detection robot are described in this paper. First, we propose a trajectory tracking control algorithm based on RTK-GPS for hexapod robot. ln extreme environment, for example a mine field, it is necessary for robot to observe the position and follow the reference trajectory. So we constructed a hierarchical control system including the high and low authority controllers. The low authority controller is sliding mode controller that is useful for robot system which contains the nonlinear characteristics at the drive system. And the high authority controller changes the gait by using GPS data. Next, we propose a foot control by using non-contact impedance control (NCIC) when hexapod robot acts on mine avoidance. NCIC can regulate virtual impedance between the end-effector and external objects using position information. First, a controller put a virtual column on a mine position by using GPS data and potentiometer. The virtual force is calculated from the non-contact impedance and the foot can avoid the mine position owing to revise base reference. We have already verified the usefulness of these schemes by simulation and experiments.
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岸本 幸一郎, 梅田 和昇
2003 年 69 巻 679 号 p.
669-675
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Pushing operation is one of the important operations for a man so as to carry an object, especially when the object is heavy. This paper proposes a practical vision system that is applicable to the pushing operation for mobile robots. The method measures the motion of the pushed object from local visual information only. Three-dimensional positions of points on the object are measured using motion parallax, and translational and rotational motion of the pushed object is measured by tracking the points. The method is formulated by using a robust nonlinear least square method. Experiments to show the effectiveness of the proposed method is performed with a constructed mobile robot for pushing operation.
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田中 幸悦, 梶谷 誠, 金森 哉吏, 阿部 靖則
2003 年 69 巻 679 号 p.
676-682
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
We are developing positioning systems for mobile robots working at construction sites. In earlier work, we investigated the use of pillars as reference points at construction sites for a position recognition system, and reported on the performance of a prototype system. To further increase the flexibility of the robot system, we have developed a new self-position measurement system for the mobile marking robot. This new system is aimed at expansion of the work area of the marking robot. The system is composed of a prototype of a laserpointer robot and a marking robot with laser-spot detectors. The marking robot uses a point of laser light projected onto it by the laser-pointer robot, placed at a reference point, to determine its position. This report outlines the method for the self-position measurements and describes the performance of the system in a field test.
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山田 貴孝, 小石倉 太郎, 水野 雄登, 三村 宣治, 舟橋 康行
2003 年 69 巻 679 号 p.
683-690
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
In this paper, we discuss stability of 3 D grasps by using a three-dimensional spring model (3D spring model). Many works described stability of frictionless grasp. These works used a one-dimensional spring model (1 D spring model) for representation of frictionless contact as a matter of course. However, 1 D spring model involves the following two problems. (i) Displacement of finger is restricted to one dimension along the initial normal at contact point. (ii) It is not clearly considered that a finger generates contact force to the object along the normal direction only. To overcome the problems and provide accurate grasp stability, we introduce 3 D spring model. Then finger's displacement is relaxed and finger's contact force is precisely formulated. We analyze grasp stability from the viewpoint of the potential energy method. From numerical examples, we show that there exists an optimum contact force for stable grasp. Moreover, we also analyze frictional grasp by using contact kinematics of twist-rolling. By comparing frictional grasp stability with frictionless one, we prove that friction enhances stability of grasp.
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南 和幸, 大歳 努
2003 年 69 巻 679 号 p.
691-696
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
We have developed pattern transfer process transferring a micro pattern of a planer mask onto a cylindrical surface of a tube-like structure. For this process, a rolling exposure system was constructed by modifying the conventional exposure system for IC fabrication process. The deposition process of thin photoresist on the cylindrical surface by using electrophoretic resist was also developed. The 20 μm line and space pattern could be transferred on the cylindrical surface of the 3 mm in diameter glass tube. The medical applications of this process are also described. A stent, one of the medical implements, has the tube-like 3 D structures. The process developed was used to fabricate the high performance stent. The complicated stent pattern was transferred on the cylindrical surface of a 5 mm in diameter Titanium tube, and the tube was etched through by using the pattern as a mask. This process was key technology to fabricate the high performance medical implements/instruments for minimally invasive treatment.
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横山 良平, 伊東 弘一
2003 年 69 巻 679 号 p.
697-704
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Mixed-integer linear programming (MILP) can be used for a variety of optimization problems. However, it is limited to relatively small-scale problems, because its computation time increases dramatically with the number of integer variables. A decomposition method has been proposed by the authors to derive good feasible solutions of large-scale MILP problems. The method is composed of solution of original and reduced MILP master problems, solution of MILP subproblems, and assumption of values of part of integer variables, which are repeated until a suboptimal solution is obtained. The objective of this paper is to propose a strategy to determine appropriately the number of integer variables whose values are assumed by means of multistage use of the decomposition method. A multi-period operational planning problem of a heat supply system is investigated numerically to show the validity and effectiveness of the strategy. It turns out that the strategy can derive a better suboptimal solution and an effective approximate lower bound for the optimal value of the objective function.
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森園 哲也, 山田 陽滋, 山本 貴久, 梅谷 陽二
2003 年 69 巻 679 号 p.
705-712
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
There are many tasks in which cumbersome protective suits or large mass of objects to be manipulated obstruct "intuitive" skills such as picking up and grasping. Workers engaged in such tasks are distressed for inefficiency or early fatigue. However, the efficiency or fatigue will be improved if they can perform their intuitive skills even in those tasks by wearing an intelligent machine. Based on this idea, we proposed the concept of the wearable robot "SkilMate". This paper proposes a new type of mechanism named "wearable HEXA" as a prototype shoulder joint of the SkilMate. This mechanism is designed wearable and to give no constraint caused by geometrical factors for a wearer, so that movements of his/her shoulder necessary for the intuitive skills are not impeded and interfered. Detail of the mechanism and its design process are described, and evaluation for an experimental mechanism manufactured along the design process is demonstrated.
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廣川 俊二, 有吉 省吾, 朝長 裕樹, 梶山 貴史
2003 年 69 巻 679 号 p.
713-720
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The new technique originated by S. Banks was further developed in this study for the measurement of 3 D motion from 2 D perspective projections of knee prosthesis. The technique used measured perspective surface geometry to implement a contour matching based position/orientation estimation scheme. The estimation was processed in two stages. The first stage estimation was done on the assumotion of orthogonal projection. Then, the second stage estimation was succeeded based upon the perspective projection to accomplish more accurate estimation. Computer model studies indicated that the technique could archive sufficient accuracies, especially the advantage in the application of the second stage estimation. lt is proposed that this technique can provide a unique and valuable new tool for quantifying the performance of existing total knee designs and for developing improved knee replacement devices.
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郡原 宏
2003 年 69 巻 679 号 p.
721-726
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The gear honing is well used recently as a gear finishing method. Under such circumstance, an extension of the grinding wheel life and a decrease of the processing cost are the urgent demand. In this paper, a new honing method of extending the grinding wheel life is proposed to respond to this demand, furthermore the calculation method of both the sliding velocity and sliding angle which may affect the honing efficiency is described because of the proposed method inducing the change of the sliding-velocity and -angle according to the amount of wheel dressing. The proposed method is a method of changing the setting angle between work shaft and wheel shaft corresponding the setting distance between the both axes.
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郡原 宏, 竹ノ下 明, 齋藤 伸也, 佐藤 公紀, 臼杵 年
2003 年 69 巻 679 号 p.
727-731
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
A new honing method for extending the life of the grinding wheel is proposed in the previous paper. The method is that a setting angle between work shaft and grinding wheel shaft is changed according to the setting distance between the both axes in both process of dressing and honing. In this paper, the experimental verification on the availability of new method is reported. In the experiments, the negligible small change of the honed gear tooth profile is confirmed after the grinding wheel dressing in the amount of 10 mm.
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廣川 純夫, 本間 晃, 久保田 泰
2003 年 69 巻 679 号 p.
732-736
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper deals with a performance of a high gear ratio crossed helical gears. The substances of this study are summarized as follows. The geometrical characteristics, which include the trace of the point contact mark and the tooth bearing ellipse, are examined in the third and fourth sections of this study. A method of the design of this gears is presented in the fifth section and a pair of the gears with gear ratio 20 is manufactured for trial. The materials of the gear I and II are SCM415 and phosphor bronze, respectively. The gear I is finished after case-carburizing by grinding wheel. A performance test of the high gear ratio crossed helical gears is presented in the last section. A transmission efficiency of 86.5% is obtained showing satisfactory abilities of the gears for practical use.
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鄧 綱, 中西 勉
2003 年 69 巻 679 号 p.
737-742
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This study presents a method to enhance the bending load capacity of gear using different standard pressure angles in the front side and backside tooth profile. In this report, the calculations were performed for not only the maximum stress but also the stress amplitude from fillet to tooth root considering the gearing procedure. A larger backside standard pressure angle leads to a small tensile tooth root stress but a large compressive stress at the next or previous tooth root. As the result for the stress amplitude calculation, the increase in the backside standard pressure angle will decrease the stress amplitude at the tooth fillet except at the tooth root. Bending fatigue tests were performed for two types of normalized and induction-hardened gears to evaluate the enhancement in bending load capacity using a larger backside standard pressure angle. The standard pressure angles of the front side/backside of the tooth of test gears were 20/20 deg. and 20/30 deg. The fatigue test results confirmed the significant increase in bending load capacity by the use of a larger backside pressure angle.
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西野 隆之
2003 年 69 巻 679 号 p.
743-751
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Two methods of analyzing vibratory response of helical gear system including gearbox are proposed. In the first method, gear shaft system and gearbox system are assembled to one FE-model and response analysis is done to mesh exciting force. In the second method, response analysis of gear shaft system is done separated from gearbox system and dynamic bearing forces are evaluated. Next, dynamic bearing forces are given to gearbox and response analysis of the gearbox is done. These two analysis methods are applied to single stage gearbox that a pair of helical gears with tooth surface modification is built in. The analytical and experiment results show that these methods are effective.
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西野 隆之
2003 年 69 巻 679 号 p.
752-759
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
A vibration analysis method of helical gear system will be proposed. In this method, excitation caused by the axial movement of the distributed load on the tooth flank which is accompanied by mesh progress will be taken into account as well as the excitation caused by tooth flank error and by the change of tooth spring stiffness. This method will be applied to vibration analysis of a gearbox that has gear pairs with different tooth flank modifications and different gear axes supported by different types of bearing. The analytical and experiment results show that this method is accurate and effective enough for practical use.
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岡田 学, 賀勢 晋司, 吉本 勇
2003 年 69 巻 679 号 p.
760-765
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
For leading to greater fastening performance, the severity for requirement of dimensional and geometrical accuracies of threaded fasteners is increasing. This study, as one of the major factors relating to the above matter, treats the run-out of bearing surfaces of nuts and bolts. The purposes are to solve a probability distribution of the run-out and present related data from measurements for contributing to accuracy control and accuracy improvement. Measurement samples are taken from M 10 and M 10×1.25 nuts and M 10 bolts on the market. It is derived that the run-out theoretically shows a probabilistic feature characterized with the Rayleigh distribution or the similar one. With that statistical feature, all measurement results can be well explained. ln brief, it can be said that this study makes the statistical feature of the run-out clear and gives some related data of the actual conditions.
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三木 恒久, 高倉 章雄, 金山 公三, 山口 克彦, 飯塚 高志
2003 年 69 巻 679 号 p.
766-772
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Extrusion tests of mixed wood powders of cryptomeria with Japanese cypress are carried out at various temperatures in order to confirm the possibility of near net shape forming of wood powders. Effects of extrusion temperature, extrusion ratio and the moisture content of the mixed wood powders on the flow characteristics, bending strength and density of extruded products are discussed. The experimental results show that the fluidity of the mixed powders and bending strength and bulk density of extruded products increase with increasing temperature and moisture content of powders. However, when the extrusion temperature is too high, the bending strength and density of extruded products tend to decrease due to bubbles generated in the compacted product.
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仙波 卓弥, 冨田 直樹, 藤井 晋一
2003 年 69 巻 679 号 p.
773-779
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Two types of electroforming techniques that can produce thick electroformed coatings were developed to utilize the coatings as microgrinding tools. Sedimented abrasive grains on the cathode were agitated continuously at a low speed to increase the nickel ion density near the cathode when the low-speed agitation technique was employed. In addition, an open space 3 mm square and 15 mm in length was grooved on a cylindrical aclylic insulator that covered the columnar anode, and an attempt to fill the space with the deposited coating was made by rotating the cathode at a low speed when the low-speed rotation technique was employed. It became obvious that an electric force line was concentrated at the edge of the cathode, so that a coating with uniform thickness could not be realized when the low-speed agitation technique was employed. 0n the other hand, high-speed electroforming that can produce a thick coating 3 mm square and 15 mm in length in 18.3 hours was accomplished when the low-speed rotation technique was employed.
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佐々木 一彦, 藤田 欣也
2003 年 69 巻 679 号 p.
780-787
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Making of an artificial leg takes longer term up to two months because of the repetition of the test walking and the socket shape modification. In this study, we developed the Immediate Fitting Socket (IFS) system which enables immediate test walking and shape modeling for casting. IFS are constructed of an outer shell and a particle containing bag, whose rigidity can be controlled by the applied negative pressure. The three point load test was performed to evaluate the strength of the particle containing bag. The effect of the surface material, particle size and negative pressure were examined. The particle bag consists of two materials with different elasticity, 0.5 mm diameter particles and -650 mmHg negative pressure possessed rigidity equivalent to polypropylene. The shape modeling berformance was evaluated by measuring the circumferences of the models from a plaster imitation and three amputees. The modeling error was less than 0.5% in plaster imitation, and less than 6% in amputees. The polymer socket casted from the model was successfully utilized by the amputee.
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樋口 勝, 武田 行生, 舟橋 宏明, 松下 知己
2003 年 69 巻 679 号 p.
788-795
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper has proposed the range of design parameters of a walking machine for a leg-disabled persons and aged persons. ln order to make clear this range, we presented its dynamic model with consideration of joint clearances and elasticity of legs. A general model for analyzing contact conditions-collision, stick and slip-between bodies has been introduced for dynamic simulation of motions at several states of walking including stumbling and falling of the machine. In order to realize a stable walking a delay time of clutch control has been introduced, and its appropriate value has been clarified. The influences of joint clearance, leg stiffness and center of gravity on the stability of walking have been analyzed. The region of leg stiffness and center of gravity by which walking machine can walk stably have been made clear. A prototype of the walking chair has been designed and manufactured based on the simulation result. While walking on terrain with random steps, the body attitude angle of the prototype has been kept within ± 2 degree.
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林 洋和, 藤川 裕晃, 白井 裕, 伊呂原 隆
2003 年 69 巻 679 号 p.
796-804
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Semi-conductor manufacturers are aiming at saving initial cost (construction and land cost) and maintenance expenditure that are incurred in proportion of the clean room area. Especially for the 300 mm wafer factory, the equipments tend to be enlarged. The clean room area should be reduced to decrease construction cost by expelling the auxiliary machines out of the clean room. The auxiliary machines should be located compactly in order to minimize footprint under the clean room, and pipe length. We propose a "3 dimensional Maze method" applied algorithm to minimize total pipe length. In this research, at the auxiliary machine room of the downstairs of a clean room, the auxiliary machine arrangement problem which considered piping is modeled. We propose a new method to minimize auxiliary machine area and the total pipe length simultaneously. Simulated Annealing are used as the technique of optimization. Numerical examples demonstrate effectiveness of proposed algorithm
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榎 真一, 青山 栄一, 廣垣 俊樹, 安藤 博昭, 神野 大介, 片山 傳生
2003 年 69 巻 679 号 p.
805-811
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
The high quality of the cab design and the vibration reduction of the cab are needed for the vehicle type construction machinery. As these countermeasures, the structure analysis and vibration analysis are carried out by large-scale CAE modeled with the shell elements in detailed design stage. But, when the design change is required in the evaluation using the CAE in detailed design, we have to make large-scale CAE model again. In the result, the prolongation of the development time and the increase of the calculation cost are caused. From such background, it is necessary to be simulated the strength and the vibration of the cab at the good accuracy in the conceptual design stage in order to carry out the cost reduction of the development and shortening development time. Then, the object of our study has been established the simple finite element model based on the beam elements for carrying out CAE in conceptual design stage in the design field easily. We have studied the evaluation method of torsional rigidity for the spot-welded frame which had been difficult to be calculated, and have been modeled the frame part of the cab with beam element. In this paper, we present the simple FE model with the rhombic beam elements for the panel part. We can establish the simplified FE model of the cab for static analysis and eigenvalue analysis.
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外山 眞也, 冨田 重幸
2003 年 69 巻 679 号 p.
812-818
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents a CAD system that has a new function for automatically generating the optimal developments of sheet metal products such as ventilation pipes. Dynamic Programming was adopted to solve the problem efficiently. The fitness function is made up of two objective functions ; the first one describes the total length of bending lines each of which links two sample points ; one on the entrance and the other on the exit respectively, and the second one describes how smooth the changing rate in directions of the generated side surface is. This method makes it possible to get much better solutions than those obtained with existing other CAD system. It has been confirmed through several numerical experiments that the method proposed here is sufficiently applicable to the generation of a wide variety of development-patterns required by the industry.
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田辺 郁男, 池田 祥生, 浦野 好市
2003 年 69 巻 679 号 p.
819-824
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
As higher precision machining is required, reducing thermal deformation of a machine tool becomes more important. In the previous report, a new method for estimating optimum temperature of cooling oil on a spindle was established. Inverse analysis using neural network was used for calculating optimum temperature, because neural network is suitable for controlling non-linear phenomenon. In this report, effect of relearning by inverse analysis using neural network was investigated. At first, in the experiment, thermal behavior of a bench lathe was measured for a few basic study data of the neural network. Next, the neural network was used to learn the relationship between the measured temperatures and the thermal deformation on the bench lathe. Then, optimum temperature for cooling oil on a spindle was calculated by inverse analysis using previous neural network, and oil temperature of the refrigerator was changed to the optimum temperature. At last, new neural network using the basic study data and the controlled data rebuild up, then the refrigerator for spindle of the bench lathe was controlled by inverse analysis using new neural network and was evaluated. It is concluded from the results that the proposed relearning was effective in order to reduce thermal deformation.
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吉村 允孝, 泉井 一浩
2003 年 69 巻 679 号 p.
825-833
発行日: 2003/03/25
公開日: 2008/02/26
ジャーナル
フリー
Large-scale machine system optimization problems usually resist solution because large-scale machine systems often have a hierarchical general structure that produces numerous local optirna during hierarchical optimization. Genetic algorithms having hierarchical genotypes can be directly applied to the optimization of such problems, however the appearance of local optima during hierarchical optimization procedures often foils effective searching. To enable the global optimization of such problems, skillful analysis of the component relationships comprising the hierarchical problem allows the hierarchical structure to be divided into more tractable units. Divided optimization problems can then be optimized via multiple crenetic algorithm processes, and global large-scale optimization problems can be represented as hierarchical sets of genetic algorithm processes. The exchange of local searching information between these genetic algorithm processes enables global searching and parallel processing, both of which enhance the efficiency and quality of searching for optimum solutions to large-scale optimization problems.
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