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梶原 逸朗, 長松 昭男
1994 年 60 巻 570 号 p.
368-373
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
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木村 康治, 高原 弘樹, 大森 直陸, 坂田 勝
1994 年 60 巻 570 号 p.
374-379
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Free vibration analysis is presented for liquid surface motion in a rigid circular cylindrical tank which is rotating around its symmetrical axis at constant angular velocity. It is considered that the equilibrium surface forms a paraboloid of revolution. Basic equations of liquid motion are derived by using the acceleration potential under the assumptions that the gravity. effect is dominant in comparison with the centrifugal force and that the liquid is inviscid and incompressible. It is confirmed that both elliptic and parabolic vibration modes of free surface oscillation appear due to tank rotation. The characteristic equations for the elliptic modes are derived by applying Galerkin's method. It is noted that the natural frequencies of the elliptic mode are separated by the Coriolis force. An experiment was conducted using a model tank. A good agreement was found between the theoretical and experimental results.
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桜井 明, 井上 喜雄, 筒井 秀実, 伊藤 廣
1994 年 60 巻 570 号 p.
380-385
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In a vertical hydraulic driving system with an asymmetric load, self-excited vibration, which is different from so-called stick-slip motion, is sometimes observed. This vibration occurs only if the sliding direction of the load is downward and its amplitude increases exponentially while the amplitude of the stick-slip motion shows a limit cycle. Concerning such phenomenon, an equation of motion of two degrees of freedom which has a cross-coupling force between two masses is derived here. This theory can easily explain the phenomenon mentioned above. Experiments were also carried out and by comparing the calculated results with the measured data, it can be seen that the theory developed here is adequate. A simplified stability discriminant was also derived and was proven to be adequate as a sufficient condition by comparison with the experimental results.
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鳥居 孝夫, 安田 仁彦, 豊田 哲也
1994 年 60 巻 570 号 p.
386-393
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Nonlinear forced oscillation of a rotating circular disk excited at a fixed point in space is considered. For theoretical analysis, modal equations are derived from the governing partial differential equations. Then, based on these modal equations, the characteristics of oscillation induced by harmonic excitation are investigated. Numerical calculation is conducted for a typical case in which the excitation frequency approches the primary resonance points of the forward and backward traveling wave modes. It is shown that near the primary resonance point of the backward traveling mode, forward traveling mode oscillation occurs in addition to backward traveling mode oscillation, and conversely, near the primary resonance point of the forward traveling mode, backward traveling mode oscillation occurs in addition to forward traveling mode oscillation. An experimental analysis is also conducted, which confirms the validity of the theoretical analysis.
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伊藤 清二郎, 村上 寛, 辻内 伸好
1994 年 60 巻 570 号 p.
394-398
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A new simulation method to treat the fluid-structure interacted nonlinear problem is presented. In this method, the transformer coils are modeled as a multiple-degree-of-freedom system, which consists of lumped masses and nonlinear springs. The insulation oil in the gap between the lumped masses is regarded as a one-dimensional uncompressible fluid flow including viscous resistance. A good correlation is achieved between the experimental and analytical results using an actual scale model transformer in the verification.
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金子 康智, 梅村 直, 長嶋 利夫
1994 年 60 巻 570 号 p.
399-405
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Recently, in order to improve power plant thermal efficiency, the turbine blade, which is the most important element of the power plant, has been used under severe conditions of high loading. Therefore, for the purpose of increasing plant reliability, the blade with friction dampers has been used. This paper presents the analysis method to predict damping characteristics of the damper blades by applying the substructure synthesis method and the harmonic balance method to the bladed disk. In order to verify the validity of the analytical method proposed here, the calculated results by the harmonic balance method are compared with the results by the direct integration method. Also, the model test is carried out and the experimental data are compared with the numerical results. It is found that a large damping effect can be obtained by using the damper elements and the numerical results show good agreement with the experimental data.
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成田 吉弘, 太田 佳樹, 森賀 茂樹, 目黒 雄二
1994 年 60 巻 570 号 p.
406-411
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
An analytical method is presented for the free vibration of thick, laminated composite plates having arbitrary boundary conditions. In the analysis, the laminate theory is used to give the equivalent stiffnesses, and the energy expression is derived taking into consideration transverse shear and rotary inertia of the plate. The displacement functions are introduced in series form with boundary indices so as to accommodate any combination of free, simply supported and clamped edges along four sides. Then, the Ritz method is applied to yield a frequency equation for the problem. In numerical examples, natural frequencies are calculated for specific examples to establish accuracy of the solution by examining convergence and comparison, and the effects of the shear correction factor on the calculated freqencies are studied.
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中川 正紀, 堀内 敏彦, 亀谷 正嗣, 菊地 勝昭
1994 年 60 巻 570 号 p.
412-417
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
On-line testing is a useful way to investigate nonlinear dynamic behavior of structures subjected to seismic excitation. The pseudo-dynamic testing methed is usually used for the on-line testing, in which the time duration in testing to realize the deformation within one time increment is much longer than that in calculation. However, to obtain the dynamic reaction force from on-line testing, the real-time excitation is required. For this purpose, we developed a real-time on-line testing system controlled by a parallel processor with high-speed A/D and D/A converters. The real-time controller can simulate the seismic response of structural models with up to 100 degrees of freedom within the frequency range of 10 Hz. The applicability of the real-time on-line testing method was verified by a comparative shaking table test.
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観音 立三
1994 年 60 巻 570 号 p.
418-423
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Valve noise is one of the most important types of noise in a rotary compressor. In order to predict this noise, the following methods were used. The noise source was predicicted by analyzing the gas flow and the valve behavior by dividing the gas flow path into four fields. The pressure pulses radiated from the tail pipe of a muffler ere predicted using the transfer matrix method which is applied three-dimensional modal analysis to the muffler cavity. Experiments were performed to confirm the validity of above methods and it was shown that the predicted results were in satisfactory agreement with the experimental data up to high frequencies.
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原 進, 吉田 和夫
1994 年 60 巻 570 号 p.
424-429
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
For positioning control of flexible structures, it is important to reduce residual vibration after the positioning is completed. If a positioning controller and a vibration controller are designed independently and abrupt switching is performed from the former to the latter, the moving structure suffers from impact and additional vibration is caused. This paper presents a method of simultaneous synthesis both motion and vibration controllers, using a time-varying criterion function for optimal control. This method is applied to positioning control of a flexible structure. The usefulness of this method is verified theoretically and experimentally.
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江 鐘偉, 長南 征二, 井林 純
1994 年 60 巻 570 号 p.
430-437
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper describes a study on the multi-mode vibration control of a miniature flexible robot arm driven by piezoelectric bimorph cells. It is well known that n actuators and sensors are required to control the nth-mode vibration of the flexible arm. However, the installation of many actuators and sensors makes the control scheme of the system complicated. In this study, the piezolectric bimorph cell was used as a distributed actuator to control the multiple-mode vibration. It is shown both theoretically and experimentally that the distributed actuator suppresses the higher-mode vibrations effectively as well as the fundamental mode of the arm.
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谷 順二, 三浦 英久, 裘 進浩, 大友 規矩雄
1994 年 60 巻 570 号 p.
438-442
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents a method to control the vibration of an arch system. The arch system consists of a clamped arch with piezoelectric actuators. At first, this study presents the analysis of the vibration problem caused by periodic excitation. The problem is solved by means of the transfer matrix and modal expansion methods. Next, with application of H
∞ control theory to the arch system, a numerical simulation of and experiments on vibration control are performed with a piezoelectric actuator. The result shows the effectiveness of this control method for the decrease in forced vibration of the arch system.
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谷 順二, 裘 進浩, 三浦 英久
1994 年 60 巻 570 号 p.
443-449
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents a method to control the vibration of a cylindrical shell system. The cylindrical shell system consists of a polymeric film in the middle and one piezoelectric film on each side. The piezoelectric films are divided into several parts, some of which function as distributed actuators. Analysis of the shell vibration under periodic excitation is performed by means of the modal expansion method. A controller is designed based on H
∞ control theory and the results of modal analysis. Numerical simulation and experiment were carried out using the designed controller and the results show good agreement, as well as the effectiveness of this method in suppression of forced vibration.
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出島 一直, 大石 哲男, 岡田 養二
1994 年 60 巻 570 号 p.
450-454
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Magnetic bearings are being increasingly used because of their noncontact support capability. For some applications, a power motor should be installed between the radial magnetic bearings. In the previous paper, a new method of levitation control of a synchronous-type motor as introduced, that is, the radial position as well as the rotation of a PM rotor can be controlled. For analysis the rotor was assumed to have a sinusoidally distributed magnetic flux, while the stator had an arbitrarily distributed flux. In the experiment, the stator was approximated by 12 concentrated windings. This paper introduces the analysis of the least number of stator poles. The stator flux is assumed to be produced by the concentrated windings which produce the spatial higher harmonics. The rotor is assumed to have the sinusoidal distributed flux which can be produced by a permanent magnet. A simple experiment is conducted to confirm the validity of the analysis.
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有坂 寿洋, 小野 京右, 佐藤 洋
1994 年 60 巻 570 号 p.
455-461
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In order to make clarify chattering, the unstable vibration of the roll-strip coupling system, the eigenvalue analysis is carried out using a roll-strip coupling model. In this model, a mill is simplified to a four-degree-of-freedom vibration system. The effects of dynamic frictional forces acting on the strip and rolls are also considered. From parameter studies, the following results are obtained. First, a bending moment due to the dynamic frictional forces destabilizes the natural mode of vibration of the roll-strip coupling system at the resonance of the roll and suspension systems. Second, there exists a closed region of roll suspension stiffnesses, in which one of the eigenvalues of the roll and suspension system has a positive real part value. Under this condition, a strong instability of the roll-strip coupling system is induced at the natural frequency of the roll and suspension system.
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崔 宏武, 谷 順二
1994 年 60 巻 570 号 p.
462-466
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In this paper, the governing equation for a pipe conveying fluid is modifired by including the influence of the following factors : (1) difference between pressures within and around the pipe ; (2) boundary conditions of fluid and pipe. The solution of the new general basic equation depends on the boundary condition. Application of the new equation to a cantilevered pipe dischanging fluid gives a result closer to the experimental value than the previous theoretical one. The critical speed of the cantilevered pipe aspirating fluid obtained from the new theory is higher than that obtained from the previous theory.
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福山 寛正, 染谷 常雄
1994 年 60 巻 570 号 p.
467-475
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
The dynamic characteristics of a rotor system supported by an oil-lubricated spherical spiral groove bearing (SSGB) were analyzed. In the analysis, the characteristics of SSGB were calculated by means of the finite-element method (FEM), and the rotor system had six degrees of freedom. The dynamic stability of the rotor system was analyzed by means of a nonlinear orbit method using the Runge-Kutta-Gill method. The dynamic imbalance response was analyzed and the limiting imbalance was also calculated. Moreover, the effects of sudden elimination of the upper bearing upon stable rotation were also considered. The validity of this analysis was examined by several experiments.
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下田 郁夫
1994 年 60 巻 570 号 p.
476-481
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Dampers using viscosity resistance of highly viscous materials are already been in practical use as seismic devices for multispan continuous bridges and buildings, thus making rationalized earth-quake-resistance design possible. The viscous shearing damper generates no hydraulic pressure. On the other hand, as the viscosity of viscous material becomes higher, considerable non-Newtonian character and viscoelastic behaviour appear. Dynamic characteristics of a viscous shearing damper and dynamical models of viscoelasticity of highly viscous material (SA-P) using mainly polyisobutylene and other polymer substances were examined by means of a spectrometer and dynamic actuator. A general empirical formula on viscous shear resistance and modelling of viscoelasticity by introduction of the Maxwell model with nonlinear elements were proposed.
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安田 仁彦, 後藤 良次
1994 年 60 巻 570 号 p.
482-489
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
As a basis for developing experimental identification techniques for boundary conditions of a linear vibratory system, a technique for a beam is proposed. The proposed technique enables one to determine, using data of dynamic responses of a beam, the boundary conditions in terms of spring constants, damping coefficients, and equivalent masses and moments of inertia. Numerical simulation is conducted, and the applicability of the proposed technique is show.
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上坂 充, 吉田 義勝, 宮 健三
1994 年 60 巻 570 号 p.
490-497
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Development of a large bulk superconductor of MPMG-YBaCuO having large critical current density makes high-Tc superconducting levitation very promising. Its attractive features are intrinsic position stability and strong damping. The mechanism of the damping in MPMG-YBaCuO was theoretically analyzed and it was found that its source was energy dissipation due to flux flow. Numerical analysis with the J-E constitutive relation based on the flux flow and creep model could simulate dynamic magnetic force properties such as damping in coupled vibration, time variation and hysteresis. The theory and numerical results were verified by the experiment.
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長南 征二, 江 鐘偉, 増井 慶次郎
1994 年 60 巻 570 号 p.
498-505
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Deformation control of a silicon-wafer slicer cutting a crystal ingot is studied analytically. The thin rotating blade is clamped at the outer boundary and prestressed in the radial direction, while the inner periphery is subjected to stationary, distributed in-plane and lateral slicing loads from the workpiece. The deflection of the blade is obtained analytically by introducing the multi-model expansion method, further applying the Galerkin method to the governing equations of the system. Numerical results are presented for an actual SUS 301 blade cutting a 6"-diameter silicon ingot at a speed of 1550 rpm. Two control schemes that maintain the flatness of the rotating blade are examined in detail. In the first scheme, a pair of concentrated lateral forces are applied to the blade to reduce the blade deflection. In the second scheme, a pair of moments are also applied to the blade to improve the flatness of blade. Simulation results obtained show that the application of control moment is more effective than the simple lateral forces to the improvement of flatness of the slicing blade.
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多田 幸生, 古井 秀介
1994 年 60 巻 570 号 p.
506-512
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Structural optimization wherein the criterion is the minimization of control cost with quadratic form of state variables and the control input is dependent on the initial state of the system. This paper formulates an optimization problem for a 3-dimensional truss structure, taking the viewpoint that the initial state is a deformed one by static loads and also taking account of the uncertainty of the external loads. In order to consider the uncertainty of the loads, the expected value of control cost is adopted as an objective function. Furthermore, an effective method for calculating the expectation of the control cost and its sensitivity is proposed. Some numerical examples show the effectiveness and necessity of the proposed method.
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尾田 十八, 松本 徳之, 王 安麟
1994 年 60 巻 570 号 p.
513-518
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents the selection method of control members for adaptive truss structures using genetic algorithms (GA). The adaptive truss structure can maintain its function against environmental changes. However, the design problems of adaptive truss structures have been studied under the condition that the control members are given in advance. Therefore, we cannot evaluate whether these control members are actually effective for the fulfillment of functional demands. In this paper, this problem is treated as a combinatorial optimization problem, and a GA is used as a searching method.
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田中 正夫, 平 俊男
1994 年 60 巻 570 号 p.
519-524
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
At the conceptual stage of structural design, subjective decisions play an important role based on sensory and aesthetic evaluation of the design object, since they are scarcely considered in the following stages in which objective technical decisions are dominant. Decision-making is vague for the sensory design aspects, and it is hard to extract them as design knowledge through conventional interviews of human designers. Past design cases are the results of hidden reasoning processes and contain the implicit design rationale of the human designer. A case-based approach is a possible way to deal with such a subjective process. In this article, we discuss a method to identify the relations among structural attributes and sensory evaluation from past design cases and to utilize them for design candidate generation. A conceptual design assistant is considered for a structural system by taking sensory aspects as well as structural ones into account. The assistant system is examined for the case of arched bridge design.
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中野 政身, 渡辺 富夫
1994 年 60 巻 570 号 p.
525-530
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
The lip-shape recognition of Japanese vowels utilizing a stereoscopic vision system has been performed to enhance the discrimination of five vowels by machine lip-reading. The opening angle P
4 between the upper lip and the lower lip is selected as the typical three-dimensional feature parameter of lip shape, in addition to the usual feature parameters such as the width P
1 and the height P
2 of the lip shape and distance P
3 between the tips of the upper lip and the chin. Compared with the 3 two-dimensional parameters P
1, P
2 and P
3 used in a single-vision system, the 3 and 4 three-dimensional parameters led to the significant increase of discrimination rate, and in particular, the discrimination rate by the 4 three-dimensional parameters was more than 90% for every tested subject. Recognition for an unspecified subject was also examined, based on the selections of the variance-covariance matrix and the mean vector of feature variables, by which the Mahalanobis' generalized square distance and the maximum likelihood discrimination function were determined.
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奥山 栄樹, 清野 慧, 守時 一
1994 年 60 巻 570 号 p.
531-537
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents transfer functions that include the characteristics of sensors, in the case of measurig straightness using sensors, e.g., 2-point method. When sensors exhibit symmetrical spatial frequency response regarding the center of their aperture, difference in their spatial frequency response causes phase shift in the results of measurement. When sensors show asymmetrical response with respect to the aperture, to avoid deviation of gain in the low-frequency domain, it is important to grasp the center of gravity of sensor's intensity in the spatial domain. In the case of the 3-point method, difference in the sensors causes deviation of the transfer function of the system. However, in the case of differential laser autocollimation, the transfer function is stable.
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一宮 亮一, 石川 淳, 藤田 英隆
1994 年 60 巻 570 号 p.
538-543
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A new method of measuring the liquid and solid in a container has been investigated. A speaker mounted upon the end face of the container emits white noise, and the air in the container resonates. The resonant frequency of the air in the container depends upon the volume of the air. This paper deals with the measurement of fluctuating volume with time. The simplified measuring equipment has a speaker fixed in the container. Experimental and calculated results show that this measuring method utilizing sound frequency is very useful and can be used to measure fluctuating volume every 0.1 seconds.
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磯部 佳成, 加藤 泰生, 香川 正信
1994 年 60 巻 570 号 p.
544-549
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
For thermal analysis of the grinding phenomenon, it is necessary to measure the temperature of a microscopic area in a very short time. A new infrared radiation thermometer using optical fiber was developed for determining the response time and the measuring area. The minimum response time was 3μs and the diameter of the measuring area was limited to just 110μm. Consequently, this thermometer was capable of measuring the exact grinding temperature which correlated with calibration curves of S45C and the grinding wheel (WA80JV). If the heat source area is larger than the measurable area, the obtained value directly indicates the temperature of the grinding wheel. In the case of an area smaller than the measurable area, modification using an equation including the distance and the area of heat is necessary.
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福田 幸一, 坂本 正史, 水垣 善夫
1994 年 60 巻 570 号 p.
550-556
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A noncontact directive sensor for detecting an angle of a line normal to a curved surface made of ferromagnetic material has been developed. This senser can be used for measuring the accuracy of 3D-shapes, such as molds and dies on machine tools, and autonomous tracing of industrial robots. This sensor has a permanent magnet which can be tilted in any direction and four Hall elements for detecting the angle. The angle is computed from Hall voltages originating from the magnetic flux density. The distance between the curved surface and one magnet end can be detected by means of Hall elements. The experimental results showed that the resolution of the angle was 0.02 degrees, the mean of measurement error was 0.2 degrees, the standard deviation of measurement error was 0.15 degrees and the resolution of distance was 0.5μm around 1mm.
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則次 俊郎, 安藤 文典, 吉川 智之
1994 年 60 巻 570 号 p.
557-562
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A rubber artificial muscle has be feature of light weight and mechanical flexibility due to its own structure and air compressibility. Hence it may be suitable for a robot which has to safely operate for human. However, the air compressibility makes accurate control difficult. This study aims to clarify the fundamental control performances of a rubber artificial muscle actuator. Continuous path control, force control and compliance control are executed. A pressure control system is constructed to improve the pressure response. It is shown that satisfactory continuous path control can be accomplished by means of feedfoward compensation. Furthermore, it is confirmed that this actuator is useful for control of delicate force and high compliance.
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西堀 賢司, 李 向軍
1994 年 60 巻 570 号 p.
563-568
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper describes an arrangement of optical devices in a computer-controlled liquid manometer which has been described in our previous paper. A configuration of a laser diode, two lenses, a glass tube manometer and a position-sensitive detector (PSD) is optimized based on optical principles. The spotlight directed at the bottom of the float located inside a glass tube manometer is focused nearly on the surface of the PSD, which is placed vertically to the optical axis of the lens. It was confirmed that the extent of movement of the image on the PSD increases almost linearly with increase in displacement of the float. When the float is placed at the zero position, the spotlight on the float is very small.
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真田 一志, 北川 能
1994 年 60 巻 570 号 p.
569-576
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A two-layered neural network was applied to adaptive control of a servo mechanism. The two-layered neural network is simple and can be built in a structure corresponding to inverse dynamics of a controlled plant. A demand signal, previous output signals of a plant, and previous control input signals are fed into the network. The output of the network is control input and is fed into a controlled plant. Initial weights can be set using information on nominal plant parameters. The weights are updated by a back propagation strategy with a normalized learning rate which may specify the rate of convergence of learning. Through experiments using an electrohydraulic servo motor system, the validity of the neural network controller was examined. Adaptation function of the neural network was demonstrated.
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和田 洋, 小菅 一弘, 福田 敏男, 渡辺 桂吾
1994 年 60 巻 570 号 p.
577-582
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper proposes a method to design a force controller based on frequency characteristics. Generally, force control algorithms are classified into two types, the explicit force control algorithms such as Hybrid position/force control and the implicit force control algorithms such as impedance control. The explicit force control algorithms control the contact force directly, implicit force control algorithms control the manipulator motion-force relation. Recently, the equivalence of these two types of algorithms has been shown by A. A. Goldenberg (1992), and R. Volpe and P. Khosla (1993). In this paper, we propose a method to design an explicit force controller based on the equivalence to the impedance controller, so that the resultant control system has the desired frequency characteristics. The method is applied to a manipulator with one degree of freedom and experimental results illustrate the effectiveness of the proposed method.
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田中 一男, 佐野 学
1994 年 60 巻 570 号 p.
583-590
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Recently, fuzzy control has been applied to many practical industrial applications. However, as one of the disadvantages of fuzzy control, it is said that we lack, at present, analytical tools for fuzzy control systems. In this paper, a design method which can quantitatively evaluate control performance is proposed for fuzzy optimal control systems. The feature of the design method is to consider not only the dynamics described in consequent parts but also the influence of fuzzy partitions defined in premise parts. The solution of an optimal feedback law consists of two steps. First, a fuzzy system, proposed by Takagi and Sugeno, is approximated by a linear time-varying system. The well-known complex method is used for the approximation since the problem of finding optimum parameters of a linear time-varying system which minimizos the mean squares error criterion is reduced to a non-linear programming. Next, the optimal feedback law is obtained by using the optimal control method for linear time-varying systems. Finally, the effectiveness of this design method is verified by simulation results.
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舟橋 康行, 塩谷 利弘, 山田 貴孝
1994 年 60 巻 570 号 p.
591-596
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In the previous report, we investigated the optimal fingertip force for 3-fingered robot hands in two-dimensional space. Generally robots manipulate objects in three-dimensional space. In this report, we consider three-dimensional space manipulation. As with the two-dimensional case. the problem is reduced to a linear programming problem, where the optimal solution is obtained via three-stage optimization solvable by the simplex method. However, in this paper a new criterion is introduced, which leads to a more desirable solution.
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佐野 明人, 古荘 純次, 大脇 智徳
1994 年 60 巻 570 号 p.
597-604
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A robot under end-point force control may often exhibit unstable behavior upon contact with the environment. To avoid these dynamic problems, control gains are usually reduced until stable behavior is obtained. In this study, dynamic compensators are adoped in force control loop in order to maintain high control gains. The force control of robot manipulators is analyzed in consideration of the flexibility of the driving system. The experimental results show that the proposed control methods give quick force responce, and do not have so sensitive properties to parameter variations.
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柴田 崇徳, 大川 一也, 谷江 和雄, 川崎 寛司
1994 年 60 巻 570 号 p.
605-611
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Behavior-based robotic systems have been successfully developed for a wide range of planar ground-based tasks. This paper proposes a behavior-based robotic system wich consists of multiple robots. The configuration of the system is a centralized one and there is a master robot acting as a leader. The other robots are used as slaves to sense their environments. The master robot collects the sensory information for fusion and integration so as to determine behavior of the system in its environment. If some slave robots malfunction, the master reorganizes the other slave robots to compensate for the malfunctioned robots. Using this characteristic, the system is able to carry out tasks in dangerous environments. To illustrate the performance of the proposed system, simulations are carried out while dealing with moving tasks in unknown or dangerous environments.
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稲毛 敏行, 橋本 豪之, 對馬 一憲
1994 年 60 巻 570 号 p.
612-617
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In this paper we describe the circular path control of a horizontal two-link robot driven by a stepping motor. The stepping motor is less utilized for the robot-manipulator system than the D.C. servomotor, because it has a demerit called the step-out phenomenon. However, the stepping motor has the merit of not requiring a rotary sensor, and thus its control system is easily prepared. In this report, seven velocity patterns are used to perform circular path control. Varying the control time which the robot draw a circular path, the deviation between the theoretical path and the experimental one is discussed for each velocity pattern. Based on the experimental results, it is recommended to utilize the synthetic velocity pattern at the initial velocity for fast and highly accurate circular path control without the step-out phenomenon.
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方 義, 白樫 正高
1994 年 60 巻 570 号 p.
618-624
発行日: 1994/02/25
公開日: 2008/02/26
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フリー
Numerical analysis is carried out in order to express the mixed lubrication characteristics between piston and cylinder in the swash-plate type piston pump and motor. The distributions of fluid film pressure and the contact force between piston and cylinder are calculated, and λ(the contact ratio)is obtained for both pump and motor strokes. The lubrication characteristic is expressed by the relationship between λ and S
0(the ratio of dynamic pressure to static pressure). The validity of the numerical analysis is discussed through comparison with the experimental results reported so far by the present authors. It is shown that the lubrication characteristic between the piston and cylinder is expressed by the λ-S
0 curve independent of the operating conditions such as the pressure or rotation speed.
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賀勢 晋司, 孫 培
1994 年 60 巻 570 号 p.
625-631
発行日: 1994/02/25
公開日: 2008/02/26
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フリー
This paper aims to clarify the mechanism of self-loosening return rotation of threaded joints subjected to transverse impact. Slippage, occurring in the parts of mating threads and a bearing surface, and relative displacement between two fastened plates, are considered through an approximate vibration analysis. The elastic torsion of a bolt shank expected to occur during slippage of the mating threads is supposed to be the most significant factor in the return rotation based on the previous results obtained by one of the authors and others, following which a fundamental idea is presented to explain the occurrence of the return rotation. The experiments support the idea in an oil lubrication well. Thus, the idea presented in this paper is applicable to the present problem.
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田村 進, 矢畑 昇
1994 年 60 巻 570 号 p.
632-638
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Reed valves used as part of compressors or engines are frequently subjected to impact fatigue fracture caused by repeated collision against a valve seat or valve stopper, but its mechanism has been made clear yet. In this study the effect of seat shape and valve thickness on the impact fatigue of valve was experimentally investigated with a fatigue machine developed using a fluidic device previously. The results obtained can be summarized as follows. (1) The seat shape which induced complicated motion such as overshoot or torsion in the valve after collision decreased remarkably the impact fatigue life of the valve. (2) Valve thickness did not influence impact fatigue life as evaluated by impact velocity instead of impact force.
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黒河 周平, 有浦 泰常
1994 年 60 巻 570 号 p.
639-644
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
The authors have already developed a program for numerically simulating the tooth bearing considering tooth flank configurations and alignment errors under no load. With application of 3-dimensional FEM analysis, a method for calculating the tooth contact patterns of cylindrical gears under load is proposed. First, tooth deflections of mating gear pairs are calculated using FEM. Boundary conditions are obtained from the results of tooth bearing analysis under no load. Loads are distributed to tooth flanks according to the separation between contact surfaces. By transformation of the deflections to the errors of the mating tooth surfaces, the former can be expressed as tooth flank configurations under no load. Second, these transformed tooth flank configurations, which are constructed from tooth deflections, are superposed onto the actual values obtained under no load. Then contact patterns can be calculated using the algorithm under no load without modification. With this method, contact patterns similar to actual ones are obtained without iteration. This indicates that the tooth bearing analysis under no load is important in applying this method for obtaining boundary conditions.
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日高 照晃, 王 宏猷, 石田 武, 松本 和幸, 橋本 正孝
1994 年 60 巻 570 号 p.
645-653
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
The K-H-V type planetary gears with cycloid gears have been used in an industrial robot and a machine requiring precise positioning. The rotational transmission error of the K-H-V type planetary gears with cycloid gears should be as small as possible in order to apply these planetary gears in various industrial fields. In this paper, the K-H-V type planetary gears with cycloid gears and three crank shafts were transformed into a two-dimensional model with twenty degrees of freedom, in a plane perpendicular to the input and output shafts, and the manufacturing and assembly errors were also transformed into the equivalent error so as to determine the rotational transmission error. Using the model and equivalent error, the theoretical rotational transmission error was analyzed, and agreed relatively well with the measured one.
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吉田 彰, 宮西 希一, 大上 祐司, 山本 和弘, 木村 治宏, 佐藤 悟久
1994 年 60 巻 570 号 p.
654-661
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Carbonitrided gears having three kinds of standard pressure angles were fatigue-tested using a power circulating gear testing machine, in order to elucidate the failure mode and changes in tooth profile and dynamic performance during the fatigue process. Two kinds of failure modes were observed. One was tooth breakage due to bending at tooth fillet, the other was spalling near the working pitch point. Surface durability of gears for spalling depended on the peak amplitude of the ratio of orthogonal shear stress to Vickers hardness. The surface durability was higher with smaller pressure angle. Under the same Hertzian stress, the bending fatigue life of a gear with the smallest pressure angle was the longest. The fatigue strength evaluated under normal load increased with increasing presure angle. The changes of the dynamic performance during the fatigue process were nominal for all three kinds of standard pressure angle.
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森脇 一郎, 福田 拓也, 渡部 洋一, 齋藤 憲司
1994 年 60 巻 570 号 p.
662-667
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
A Global Local Finite Element Method (GLFEM) has been applied to the analysis of the gear tooth stress field. The GLFEM is a numerical analysis technique in which finite element solutions and classical analytical ones (global function) are superposed in the global local domain on the basis of the energy principle. Hence, the reliability of the GLFEM greatly depends on which solution is used for the global function and/or which portion is selected for the global local domain. In the present paper, therefore, such effects on calculated stress field are discussed. Consequently, it is confirmed that Kelvin's solution is the most convenient one. Furthermore, the Lagrangian constraint is used for guaranteeing continuity of displacement on the boundary between the global local and local domains, but the constraint is not achieved sufficiently. Hence, sufficiently large area must be taken for the global local domain.
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香取 英男, 横川 和彦, 林 輝
1994 年 60 巻 570 号 p.
668-674
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Little research has been done so far on the development of a simplified design technique for noncircular gears. Such a technique should take into consideration various kinematic constraints that exist in the noncircular gear pitch curve design process, to obtain appropriate gearing on the basis of a given angular velocity ratio curve. It seems that no generalized design technique has yet been established. This study used design specifications such as an angular velocity ratio curve (types of curves in individual segments and their coefficients) and center distance to design a pair of noncircular gears. The center distance was kept constant. The design process for the pitch curve was obtained and extracted from various kinematic constraints. Based on thses results, We developed a design automation technique for the pitch curve for noncircular gears, with given arbitrary angular velocity ratio curve.
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鄧 鋼, 丸山 昇, 森川 邦彦, 人見 宣輝, 加藤 正名
1994 年 60 巻 570 号 p.
675-679
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Flash temperature is indicated by AGMA as a suitable index for evaluation of the scoring resistance of gears. In the AGMA formula, flash temperature is divided into flash rise of temperature and initial temperature, and the latter is suggested to be the temperature of oil inlet. In this research, the initial temperature and its distribution of carburized spur gears were measured by using of fine thermocouples. The results show that initial temperature is much higher than the temperature of oil inlet, and it is strongly affected by rotational velocity, tooth surface roughness, rate of lubricant supply and the extent of profile modification. It is found that lower roughness, appropriate extent of profile modification and higher rate of lubricant supply are effective for decreasing the initial temperaure, which results in the improvement of the scoring resistance of gears.
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永村 和照, 寺内 喜男, 池条 清隆, 烏谷 勉
1994 年 60 巻 570 号 p.
680-686
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
This paper presents a study of the vibration and noise of an internal gear drive. A running test was carried out using test internal gear pairs with five contact ratios and a power circulating-type internal gear testing machine. The circumferential vibration acceleration of the test internal gear, the tooth root stress, the torsional vibration of the internal gear shaft, and the gear noise were measured. By comparison with measured data, the dynamic characteristics of the internal gear drive were discussed.
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山口 勝美, 中本 剛, 北野 晶之, 鈴木 雅邦, Abbay Petros Abraha
1994 年 60 巻 570 号 p.
687-693
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
Composite-type alloyed steel powder has drawn great attention in recent years in forming high-strength sintered metal. The powder consists of iron and additions of nickel and molybdenum which adhere to the surface of the iron particles. This type of sintered alloy steel causes excessive wear of tool during cutting. The purpose of this study is to improve the machinability of the sintered alloy steel by adding nonmetallic materials. Experiments show that the addition of 3% glass to the sintered alloy steel increases tool life by 100 times. In order to clarify the mechanisms of the increase of tool life, the worn face of the cutting tool is examined using an electron probe microanalyzer (EPMA). The analysis shows that the glass additive acts as a protective film and lubricant during cutting with silicon nitride and tungsten carbide tools, respectively.
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十河 宏行, 阿部 雅二朗, 伊藤 廣
1994 年 60 巻 570 号 p.
694-700
発行日: 1994/02/25
公開日: 2008/02/26
ジャーナル
フリー
In the previous paper, dynamic behavior of a lifted load on a propelling crawler crane was studied. A suitable simulation model, which can take into account road shapes, was developed. In this study, numerical calculations were made for the dynamic load factor of a crawler crane with a lifted load during propelling. Consequently, the effects of road, working radius and propelling speed on the dynamic load factor have been clarified. A new ratio, "increase ratio of dynamic load factor, " which will be useful in the calculation of a rated load during propelling with a lifted load is proposed.
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