JSME international journal. Ser. C, Dynamics, control, robotics, design and manufacturing
Print ISSN : 1340-8062
Volume 37, Issue 4
Displaying 1-25 of 25 articles from this issue
  • Hirohisa Tanaka
    1994 Volume 37 Issue 4 Pages 629-637
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Fluid power control technologies are utilized in precise and heavy-duty motion control of mobile or stationary hydraulic systems. In the Japanese market for hydraulic systems, construction machinery accounts for 40 percent, extending from excavators to construction robots, radio-controlled truck cranes, tunnel cutters, dredges and concrete pumps, as examples. Injection molding, press and processing machines make up 10 to 15 percents of the stationary hydraulic field. Continuous improvement of a mature technology is necessary. Efficiency elevation, noise reduction, promotion of mass-produced electrohydraulics and computer control are urgent issues. From these points of view, this paper introduces some newly developed components with scientific approaches : a coupled fluid force pump/motor with better mechanical efficiency, a sensor-integrated cylinder, compact proportional valves, high-speed switching valves and some hydrostatic drive systems.
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  • David Dornfeld A.
    1994 Volume 37 Issue 4 Pages 638-650
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper reviews research focussed on the monitoring of the cutting process for the purpose of determining the state of the operation. The state includes the condition of the cutting tool, the formation and behavior of the chip, and factors affecting the workpiece such as chatter and part dimensions. The subject includes sensors for process monitoring, signal processing and sensor fusion for decisionmaking and, often, process control. This paper reviews the importance of monitoring the cutting process and presents information on sensors for process monitoring. Special emphasis is on acoustic emission-based techniques and multi-sensor systems utilizing feature extraction techniques such as autoregressive models and sensor fusion techniques such as neural networks. Examples of sensor systems for cutting state determination are presented using acoustic emission and other sensors.
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  • Atsuo Sueoka, Takashi Ayabe, Yoshikazu Iizuka
    1994 Volume 37 Issue 4 Pages 651-660
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Rolling noise arises from the interaction of the vibration characteristics of rails and railway vehicle wheels through the points of contact. This paper deals with the coupled linear vibration between wheels and a rail using an approximate model with an infinite number of vehicles which are arranged with a certain periodicity on an infinitely long and straight rail installed on three distributed springs, taking the coupling in both vertical and horizontal directions into account. The vertical irregularity on the head surface of the rail is regarded as a source of excitation. As a result, it was clarified that (1) the vertical vibration of the rail, the horizontal vibrations of wheel and rail, and the vertical vibration of the wheel contribute to the rolling noise according to the high vibration level, and (2) the vibration levels are high on the rail within the narrow intervals between adjacent wheels.
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  • Hisami Ohishi, Shinichi Ohno
    1994 Volume 37 Issue 4 Pages 661-666
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
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    This paper proposes a method for estimating the sound pressure of structureborne sound included in noise radiated by an enclosure housing a machine that produces both noise and vibration. In this method, estimation is carried out without any change in the condition of installation of the machine using acceleration measured when the machine is in operation and frequency-response functions determined when the machine is not in its operation. First, the theory of this method is briefly introduced. The frequency-response functions are determined by exciting multiple points on a machine housed in an enclosure. Then this method is tested using an experimental setup in which the enclosure is housing an excitor and a speaker. It is shown that the estimated results agree well with the measured results. Finally, the error in the estimation is discussed.
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  • Lazarus Tenek H., Ichiro Hagiwara
    1994 Volume 37 Issue 4 Pages 667-677
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
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    A computational scheme is presented for single or multiple eigenfrequency maximization of isotropic and composite plates. Eigenvalue maximization was achieved by means of an optimization process which sought to redistribute the material of the plate structure in an optimal way so that a bound on the total volume was satisfied. It was assumed that the plate structure possessed a repetitious microstructure and the homogenization theory was used to obtain equivalent elastic moduli. The structural eigenvalues and modes were computed via a finite-element analysis using a shear-deformable laminated finite element which was also applied to discretize a single-layered isotropic plate. Sequential linear programming was employed to perform the optimization task. Numerical examples are presented for clamped and simply supported plates for which the natural frequencies were extremized independently as well as simultaneously. For isotropic clamped plates, the optimality of the obtained results was verified by discretizing the resultant topology with a set of finite elements, computing its eigenvalues and then comparing them with eigenvalues from a uniform plate having the same volume.
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  • Masataka Kawaguchi, Akihiro Maekawa, Nobuyuki Kobayashi, Kohei Suzuki, ...
    1994 Volume 37 Issue 4 Pages 678-684
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    According to the trend toward high performance construction machinery, designers have been designing larger and heavier arm structures than those of the current types. But such design policy causes instability in the entire body, caused especially by arm vibration in the low-frequency range of 2 to 3 Hz, and it is very difficult to control this vibration by passive techniques. This vibration has had to be reduced substantially to prevent harm to the operator. In such a situation, applications of active vibration control technology have spread to many engineering fields, e. g., tall buildings, bridges, robots and suspensions. Furthermore for construction machinery, use of this technology can solve vibration problems, which otherwise could not be controlled easily, such as arm vibration. Therefore this paper deals with modal identification of arm vibration, mathematical modeling of an active control system involving hydraulics, and numerical simulation using a LQG (linear quadratic Gaussian) control method.
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  • Mikio Maeda, Eiji Fukumiya
    1994 Volume 37 Issue 4 Pages 685-691
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Recently fuzzy control has been applied to various systems such as home electronics, manufacturing processes and production plants. Because applications to actual control systems can be risky, the stability of a fuzzy control system must be insured. For stability analysis of fuzzy control, phase plane analysis, Hurwitz's analysis in subareas, and Lyapunov's method have been proposed. In this paper, we propose a new method of stability analysis, that is, stability discrimination on the basis of display of the stability area in 3D space, the manipulated variable, the control error, and the deviation of its error. The stability is discriminated according to whether the fuzzy control map exists in the partial space where Hurwitz's stable condition is satisfied or not.
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  • Ming-Hui Liu, Isao Todo
    1994 Volume 37 Issue 4 Pages 692-698
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Exact inverse systems are not always obtained by using neural networks in many applications because of the output oscillation of the inverse systems. There are several sets of input signals to the neural networks, which give approximate inverse systems. In this paper, comparisons of the learning process are first made among them by a computer simulation with a parallelogram-type robot manipulator of two degrees of freedom. It is shown that the choice of the input signals has considerable influence on its learning speed. Secondly, two learning control algorithms are proposed for applying the results of a one-layer linear neural network to the control of a direct-drive (DD) robot. The algorithms are based on preliminary learning by a one-layer linear neural network, and can be used for shortening the time of on-line learning. The effectiveness of these algorithms is demonstrated by the experiment on the control of a DD robot.
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  • Yoshihiro Satoh, Takeshi Nagamine, Kiyoshi Sogabe
    1994 Volume 37 Issue 4 Pages 699-706
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    In order to find the mechanism of the steady-state response of a system which consists of shear loading rubber isolators and a mass, experiments for the steady-state frequency response of the system and dynamic tests for the rubber vibration isolators are conducted under the various conditions of ambient temperature and strain amplitude, and the results are considered and discussed. As a result, it is found that the amplitude and temperature response of the system interact via the temperature-dependent dynamic properties and the internal heat-generation rate of the vibrating rubber isolator. On the basis of this result, a new method for the analysis of the steady-state response of the system is presented. Using this method, the influence of system parameters on the response is also discussed.
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  • Antonio Moran, Masao Nagai
    1994 Volume 37 Issue 4 Pages 707-718
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper analyzes, theoretically and by computer simulation, the capabilities and limitations of neural networks to be used for the identification and optimal control of nonlinear dynamical systems. It is shown how neural networks can be efficiently trained to identify the forward and inverse dynamics of systems and also to work as optimal controllers which minimize some peformance measures of the system to be controlled. The performance of neural networks when applied to the optimal control of nonlinear vehicle suspensions is analyzed and compared with the performance of passive suspensions and that of active suspensions with linear (LQ) controllers designed by linearizing the nonlinear characteristics of the suspensions around the equilibrium point. It is found that nonlinear vehicle suspensions with neuro-control show better performance than suspensions controlled with conventional LQ regulators. Some issues about the implementation of neural networks to improve its convergence and generalization properties are analyzed.
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  • Kengo Tagawa, Naruhito Shirasaki
    1994 Volume 37 Issue 4 Pages 719-727
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Dynamic interaction between industrial equipment and its supporting frames should be taken into account in the aseismic design of complex industrial structures such as blast furnaces, chemical reactor vessels, towers, or stacks. This paper aims to examine the effects of dynamic interaction on the maximum base shear distribution between two kinds of sructural components, that is, the equipment and its supporting frames, and on the vibratory energy consumption of the damping devices placed between these two structural components. The random vibration theory is applied to obtain the average peak responses of simplified interaction models placed on a base which is stimulated by ground acceleration having the standard power spectrum. The expected ratio of the maximum rocking moment shared between the two structural components of the dynamic model is obtained as a function of the dynamic characteristics of each constituent component and the interaction spring, and the maximum response is reduced by the intermediate damping devices. These results are presented garaphically for convenience so as to determine the rational aseismic design forces for each structural component.
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  • Jyh-Horng Chou
    1994 Volume 37 Issue 4 Pages 728-732
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    A new approach is proposed to analyze the stability of time-varying interval systems. Two examples are given to illustrate the improvement of the proposed method over the ones reported recently.
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  • Jyh-Horng Chou
    1994 Volume 37 Issue 4 Pages 733-738
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    In this paper, new sufficient-condition bounds on linear time-varing perturbations that maintain the stability of an asymptotically stable linear time-invariant nominal system are obtained for structured (elemental) independent perturbations. A sufficient condition for the stability of interconnected dynamic systems is also presented in terms of a bound on the time-varying structural parameter. Some examples are given to compare these proposed bounds with those existing bounds.
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  • Manabu Gokan, Kazuo Yamafuji, Hiroshi Yoshinada
    1994 Volume 37 Issue 4 Pages 739-747
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    In addition to the industrial robots for production, a large number of robots for nonindustrial use have been developed recently. These include emergency rescue and fire-fighting robots, as well as robots for amusement, educational use and security. The authors have no doubt that the robots for amusement and educational purposes hold great promise for future applications. Thus, we developed a rope-hopping amusement robot. Although rope-hopping is an easy exercise even for young children, there are several difficulties to overcome if it is to be executed by a robot. The developed robot is composed essentially of one leg, one main body attached by a pivoting joint to the top end of the leg, and a double arm holding a rope. As the main body swings forward and backward, postural stability of the robot in the vertical plane is maintained using feedback control based on "compound center of gravity of the robot". The rope-hopping motion of the robot is realized by cooperative use of the leg, the main body and the arms which rotate the rope according to the proposed path. Experimental results show that the control methods developed to achieve the postural stability and jumping of the robot coordinated with the path of rotation of the rope have useful applications in other areas.
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  • Hidenori Ishihara, Toshio Fukuda, Kazuhiro Kosuge, Fumihito Arai, Hide ...
    1994 Volume 37 Issue 4 Pages 748-754
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper proposes the concepts of the distributed micro robotic system (DMRS) and the micro cellular robotic system, which is named the μ-CEBOT. DMRS is a dynamically reconfigurable robotic system (DRRS) and will be used for task execution in a space with a small entrance which is too narrow for the entire robotic system to enter. The μ-CEBOT is one of the realization methods of the DMRS. A stacked-type electrostatic actuator (STESA) is developed for a prototype of a moving cell of the μ-CEBOT. Experiments are conducted to evaluate the performance of the STESA. The results of the control simulation demonstrate the possibility of controlling the STESA.
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  • Mikhail Svinin M., Masaru Uchiyama
    1994 Volume 37 Issue 4 Pages 755-764
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    An inverse kinematics problem of flexible manipulators is considered. The problem is of importance for compensation of tip deflections when the manipulators perform quasi-static operations. Basic equations based on both kinematic and static relationships are derived and explicit expressions of the mathematical model are presented. Based upon this model, a definition of the inverse kinematic task of flexible manipulators is formulated. Specific features of the task are considered, and a conventional approach applicable for resolving the task is analyzed. To avoid the disadvantages of the conventional approach, an implicit iterative scheme based upon step-by-step compensation for the relative elastic deflections is proposed. Corresponding convergence conditions of the scheme are derived, and applicability of the scheme is verified through simulation.
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  • Weiliang Xu, Gunter Pritschow, Karl-Hans Wurst
    1994 Volume 37 Issue 4 Pages 765-773
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper deals with the accuracy problem of a type of joint module with two rotary degrees of freedom used in a modular robot system. The error investigation concentrates on its differential gear mechanism. By dividing the gearing error into the gear transmission error due to effective eccentricity and the lost motion error due to effective backlash, errors in two output angles (i. e., joint angles) are modeled based on the engaging principle of two bevel gears. Effective eccentricity due to the tolerances in the bearing system is then determined using the geometry between the bearing and the bevel gear. By taking into account the random nature of tolerances, stochastic characteristics of the output angles' errors are calculated under the assumption that eccentricity is distributed uniformly within a circle of tolerance. On the basis of the above stochastic error formulas, an optimal method and a simplified method are proposed for allocating the tolerances. In this paper, the concrete structure of the modular joint is examined to illustrate error estimation and tolerance allocation. Finally some conclusions are drawn for improving the accuracy of this type of modular joint.
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  • An-Chen Lee, Foam-Zone Hsiao, Dennil Ko
    1994 Volume 37 Issue 4 Pages 774-782
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    Active magnetic bearings constructed with electromagnets only are usually bulky and power-consuming. This shortcoming can be remedied by adopting permanent magnets as the source of bias flux. Satisfactory results achieved by using rare-earth permanent magnets substantiate the feasibility of using permanent magnet bias in magnetic bearings. In this paper, an analytic model for permanent-magnet-biased magnetic bearings is presented. The static characteristics of a prototype are tested and compared with values estimated using this model. Manufacturing the prototype and subsequent testing offer some technological information which is important for future improvements.
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  • An-Chen Lee, Foam-Zone Hsiao, Dennil Ko
    1994 Volume 37 Issue 4 Pages 783-794
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    An active magnetic bearing with electromagnets only is unavoidably bulky and power-consuming. These shortcomings can be remedied by using permanent magnets as the source of bias flux. Unlike the hybrid magnetic bearings with the same flux path for both permanent magnets and electromagnets, so-called coplanar PEMBs, a non-coplanar PEMB with permanent magnets located between two sets of electromagnets, which are placed around the periphery of the shaft, cannot be regarded as equivalent to a pure electromagnet magnetic bearing. This paper analyzes the performance limits, such as maximum static bearing force, force slew rate, displacement sensitivity, and dynamic load capacity, of the non-coplanar PEMBs. We also campare the characteristics of this type of magnetic bearing to the co-plane PEMBs and point out their differences. Investigation of these performance limits enable better utilization of permanent-magnet-biased magnetic bearings and offer useful guidelines for the design of this type of magnetic bearing.
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  • Kazuteru Nagamura, Yoshio Terauchi, Sigit Yoewono Martowibowo
    1994 Volume 37 Issue 4 Pages 795-803
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
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    Carburized steel gears are increasingly used because of their high-strength. However, high-strength materials usually exhibit large scatter of fatigue life and fatigue strength. The fatigue failure life of a gear mainly consists of two stages : crack initiation life and crack propagation life. In this study, a model to predict crack propagation and fatigue life of a carburized steel gear was developed based on crack initiation on carbide precipitation and crack propagation life at tooth case by using the Monte Carlo simulation method. The model was applied to simulate crack propagation and fatigue life of MAC14 supercarburized steel gear. The result obtained shows that the fatigue life distribution of MAC14 supercarburized steel gear obtained from simulation and experiment is well represented by a three-parameter Weibull distribution. The crack propagation life calculation combined with the Monte Carlo simulation method was in good agreement with experimental results. The model can be implemented as an alternative procedure on the ordinary method to predict crack propagation and bending fatigue failure life of a carburized steel gear for practical design application.
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  • Yeon-Min Cheong, Kyung-Woong Kim
    1994 Volume 37 Issue 4 Pages 804-811
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    The static and dynamic performances of a floating ring journal bearing with central circumferential grooves at the inner and outer films are obtained numerically using the isothermal lubrication theory. The Elrod algorithm implementing the Jakobsson-Floberg-Olsson cavitation boundary condition is adopted to predict cavitation regions in the inner and outer films more accurately than conventional analyses which use the half-Sommerfeld or Reynolds condition. The supply pressure drop in the circumferential groove of the inner film due to the rotation of the journal and ring is taken into account. It is shown that lubricant supply pressure has a significant influence on the static and dynamic performances of the bearing since it is closely related to the extent of the cavitation region. When the supply pressure is low and the journal speed is high, the supply pressure drop results in severe starvation of the lubricant in the inner film and affects the overall performance of the bearing remarkably.
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  • Hwang-Jin Lee, Yong-San Yoon
    1994 Volume 37 Issue 4 Pages 812-818
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
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    A fully automatic algorithm is developed to obtain the complete set of nonfractionated kinematic chains for each number of links and degrees of freedom. It is a contracted graph method programmed in LISP. The number synthesis is performed efficiently using the partitioning technique implemented in a recursive procedure. The enumeration of the contracted graphs or bases is computerized by the recurrent application of the contracted graph method. In order to avoid the possible sources of human error, a newly developed automatic algorithm for the detection of the embedded rigid structure is used. The obtained results using the developed algorithm for various numbers of links and degrees of freedom are presented.
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  • John Andrews D.
    1994 Volume 37 Issue 4 Pages 819-829
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper describes a design optimization procedure to increase the working life of epicyclic gear units by minimizing the tensile fillet stresses experienced in the gear system components. An objective function is formulated together with 69 constraints (inequality and equality) which ensure that a functional system design is achieved. For the example presented, the optimum design was produced in only three iterations and reduced the maximum stress in the most highly stressed component by 54%.
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  • Jiro Matsuda, Masayoshi Koike, Hiroshi Yano
    1994 Volume 37 Issue 4 Pages 830-835
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    The injection molding of ceramics consists of four elementary processes. This paper focuses on the first process, the kneading process of mixing ceramics and organic materials. In this study, current-time curves obtained by a kneader are analyzed from the viewpoint of variance and mean, and it is demonstrated that the quality of sintered products is predictable through these analyses. The method of parameter design of quality engineering is adopted. The variation of sintered products produced after optimizing the molding process on the basis of kneader current measurements, and that of sintered products produced after optimization based on dimension data agree well. These results indicate that prediction of the variability of sintered products at the kneading stage is possible.
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  • Yasumi Nagasaka, Happy Wibisono, Hideyuki Ohtaki, Yoshio Ishikawa
    1994 Volume 37 Issue 4 Pages 836-843
    Published: December 15, 1994
    Released on J-STAGE: February 18, 2008
    JOURNAL FREE ACCESS
    This paper presents an approach to the management of knowledge bases in machining. This approach is aimed at developing a system functioning as a knowledge base management mechanism like TMS, and which can also manage different representations of knowledge bases collectively. First, we integrate the description of the knowledge base by using the symbolic-expression form. Secondly, in connection with the TMS knowledge management mechanism, we developed a new predicate-logic representation language based on PROLOG to be applied to TMS. As a result, a strategy for resolving the contradiction in TMS can be defined easily by using the meta level representation.
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