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Volume 31, Issue 10
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Ippei TORIGOE1995 Volume 31 Issue 10 Pages 1537-1544
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA new method is proposed for measuring the pulsating flow rate. Under pulsating conditions the output of conventional differential pressure flowmeters contains the acceleration term due to the fluid inertia, which causes a pulsation error in the measurement of the flow rate. In the proposed method, the stream to be measured is divided into two branch streams and each stream is constricted by the converging section of each branch channel. The pressure difference between the two channels is detected by a manometer at a point where the acceleration term of each stream cancels out. The instantaneous flow rate can then be obtained from the output of the manometer without being affected by the acceleration term. An experimental apparatus was built, and several experiments for air flow were performed with this apparatus. The results indicate that the proposed flowmeter is capable of measuring the instantaneous flow rate in the pulsating regime.View full abstractDownload PDF (1958K) -
Masahiro HARAZONO, Atsushi KURAMOTO1995 Volume 31 Issue 10 Pages 1545-1550
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn measuring characteristics of a string vibration, an electromagnetic transducer, which takes out changes of reluctance which occur because of the string vibration in the magnetic circuit, is used frequently. Turn number of the coil needs to high in order to get enough electric output, because magnetic coupling between the electromagnetic transducer and the string is very sparse. Therefore floating capacitance of the coil increases and current flows without the presence of a load. In the present paper loading effect is studied with theoretical analysis by making use of δ function for a expression of the magnetic attraction and the coupling between the transducer and the string at a particular point. The characteristic equation and the solution are obtained by making use of Laplace transform. In order to confirm the validity of the analysis results, measurements are made by laser doppler vibrometer to eliminate the influence of the equipment itself. Results show that the damping coefficients are increased by means of energy loss in the coil of the transducer. Also it is verified that the analysis results about the appearance of non-harmonic components, occurrence of beats, and increase of damping coefficients are in good agreement with experimental results.View full abstractDownload PDF (1675K) -
Atsushi KURAMOTO, Masahiro HARAZONO1995 Volume 31 Issue 10 Pages 1551-1555
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWhen an electromagnetic transducer is set in close proximity to a string for measuring the characteristics of vibration of the string, it has been analyzed that partial tones are non-harmonic because of attraction and that beats occur as a result of interference among the fundamental and the partial tones whose amplitudes are not so small. These problems can be formulated by approximating the attraction to the static component and stiffness component, and by using δ function to express the lumped force in the distributed system. The inherent elasticity of the string is accounted and the solution can be obtained by use of Laplace transform. The vibration characteristics can be analyzed from numerical calculation of the characteristic equation provided in the analysis process. Then, getting an approximated equation for the vibration frequencies, a method to correct the influence of the negative stiffness, is provided, and also a measuring system is constructed. The measured and corrected results are compared with the value obtained from Laser-doppler vibrometer, it can be identified that the corrected results have sufficient precision for practical use.View full abstractDownload PDF (929K) -
Design of Distortion LensYoshikazu SUEMATSU, Hironao YAMADA1995 Volume 31 Issue 10 Pages 1556-1563
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper a new concept of a vision sensor with fovea is presented and the possibility of the application for on-line machine control is demonstrated. The proposed vision sensor is designed approximate to the visual mechanism of the human eye, which has a fovea (high resolution attention zone) in its field of view and executes the necessary movements of viewpoint. A distortion lens plays an important role in the system, which enlarges the image in the attention zone and compresses the one in the peripheral zone. The lens has been designed in order to realize the system. The specification and characteristics are presented in detail. The results show that the proposed system will work well to recognize the environments of mobile robots.View full abstractDownload PDF (3782K) -
Haruhiko NOHIRA, Satoru NEBUYA, Masaaki HAYAKAWA, Haruyuki MINAMITANI, ...1995 Volume 31 Issue 10 Pages 1564-1572
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe purpose of this study is to develop a clinically applicable method for quantitative evaluation of the ankle joint spasticity. Spasticity has bad influence on gait of hemiplegia, therefore it is important to estimate spasticity and to reduce it efficiently. Skeletal muscle spasticity is assessed by physical therapists as increased resistance of a particular muscle group to manually induced passive movement.
In this study the passive movement was produced by the gravitational force (2.0 kilogram weight) and we recorded the response of the ankle joint. The subjects consisted of 3 healthy individuals and 11 hemiplegic individuals with slight, moderate, and severe spasticity of ankle joint muscles. In healthy subjects the foot was dorsally flexed with smooth manner and little electromyogram (EMG) appeared when the subject was fully relaxed. But in severe spastic subjects the foot movement oscillated and the EMG appeared at each dorsal flexion of the ankle joint. The quantitative measurement of spasticity could be defined by the characteristics of the ankle goniogram. Evaluation index which we proposed showed a good agreement with clinical evaluation. In addition, mathematical model of the ankle joint movement given by this test was developed supporting the evaluation index. The simulated results revealed that on the severer spastic patients, muscle spindle excitability for passive stretch increased and ankle joint viscosity was decreased.View full abstractDownload PDF (2362K) -
Yulwan SUNG, Hiroshi SHIBATA1995 Volume 31 Issue 10 Pages 1573-1578
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIt is very difficult to stabilize nonlinear systems with mismatched uncertainties, and the stabilization has been achieved under severe restrictions for the uncertainties. To solve the difficulty, this paper proposes a nonlinear dynamic control law using a new state which is generated by the term related to uncertainties and an input, and then proves its global asymptotic stability. The effectiveness of the method is illustrated through some numerical simulations. The method alleviates restrictions to a considerable extent, and its applications are expected for broader range of uncertain systems.View full abstractDownload PDF (1040K) -
Noriyoshi KUMAZAWA, Naoto ABE, Hideaki KANOH1995 Volume 31 Issue 10 Pages 1579-1585
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper develops a turn over method for distributed parameter systems that have infinite number of eigenvalues and can be stabilized by an eigen-function expansion technique. The technique has both desirable properties of a pole assignment and an optimal control law. The poles of the closed loop system which is controlled by the former law can be derived for distributed parameter systems and we can easily obtain the feedback gain without solving the infinite dimensional Riccati type differential equation. From the latter law, the obtained gain is of finite dimensional, but the optimal feedback minimizes a quadratic criterion for distributed parameter systems. The closed loop system obtained by the proposed turn over method can be interpreted as an LQ regulated system.
As result, the turn over method has both good properties of the two control laws and can shift only assigned open poles to desirable positions avoiding a difficult selection of a weight for an LQ regulator, and it gives a low sensitivity and a large stability margin to the closed loop system as well.View full abstractDownload PDF (1262K) -
Izumi MASUBUCHI, Atsumi OHARA, Nobuhide SUDA1995 Volume 31 Issue 10 Pages 1586-1594
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSLinear matrix inequalities (LMIs) describe algebraic conditions for various important properties of finite-dimensional linear systems. In this paper, we propose a unified synthesis method of controllers that satisfy LMI-conditions belonging to a certain class, which we define focusing on a structure shared by many LMIs in control theory. The class includes LMIs for some root-clustering conditions, the H∞ norm conditions and the H2 norm conditions for both continuous-time systems and discrete-time systems, and arbitrary combinations of these LMIs. The method reduces a synthesis problem to a convex optimization problem to solve a certain LMI on a finite-dimensional parameter space. A controller that solves the synthesis problem is always full-order, and we also parametrize the set of such full-order controllers with a convex parameter set. When the state of the plant is available, there exist static state feedback solutions if the problem is solvable.View full abstractDownload PDF (1555K) -
Wataru KASE, Katsutoshi TAMURA1995 Volume 31 Issue 10 Pages 1595-1600
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn a design of control system by polynomial matrix approach, it is important to consider Diophantine equation. Although the methods to solve Diophantine equation are well known, a choice of degree for stable polynomial matrix in Diophantine equation is not discussed sufficiently. In this paper, we consider this problem. As a result, we obtain a Diophantine equation which corresponds to the design of state feedback using minimal order state observer in state space. Using this, we propose a calculation method of doubly coprime factorization which gives more wide class factorization than ordinary methods. We also gives a degree constraint of free parameters in the solution of Diophantine equation which satisfies the properness of controllers.View full abstractDownload PDF (969K) -
Takuya SOGO, Norihiko ADACHI1995 Volume 31 Issue 10 Pages 1601-1607
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSConventional iterative learning control algorithms are designed to minimize the norm of output-error functions. But boundedness of the input-functional sequence is not assured. Since convergence of the output function does not imply boundedness of the input-functional sequence and the energy of the input function is limited at real systems, it is necessary to guarantee the iterative learning control algorithm generates bounded input-functional sequences. This paper proposed a method to design iterative learning control algorithms which minimize the norm of output-error functions and decreases the norm of input-error functions monotonically in order to ensure the boundedness.
The design method consists of three steps of procedure. The first one is to confirm existence of input functions that realize the desired output function. The second one is to determine a linear operator the ratio of which with the one of the object system is within a certain limit. And the last one is to construct an algorithm with a linear differential system corresponding to the adjoint operator. The last two steps are also stated in terms of transfer function matrix.
The illustrated design procedures and results of numerical simulations are presented in the final part of the paper.View full abstractDownload PDF (1099K) -
Shinichi MIYAMOTO, Shinji ARINAGA1995 Volume 31 Issue 10 Pages 1608-1617
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents designs of decoupling control systems based on the H∞-mixed sensitivity problems.
H∞-control has been studied as an effective method for multi variable systems. However, a decoupling control design based on the H∞-control is not well known. We present a design method based on the H∞-mixed sensitivity problems where the decoupling performance can be obtained if the weighting functions are chosen properly.
First, designs of one-degree-of-freedom control systems with state feedback or output feedback, will be stated. The design, of state feedback control is based on FI (Full Information) Problem and the design of output feedback control is based on DF (Disturbance Feedforward) Problem.
Next, designs of two-degree-of-freedom control systems with state feedback and output feedback, will be stated. The design consists of two stages. The first stage is to design a feedback compensator. The second stage is to design a feedforward compensator for the new plant which consisits of the true plant and the feedback compensator. This problem is equivalent to DF Problem. Even if decoupling can not be obtained with the feedback compensator, it can be obtained through the feedforward compensator.View full abstractDownload PDF (1157K) -
Tadashi EGAMI, Masayasu KIMA, Takeshi TSUCHIYA1995 Volume 31 Issue 10 Pages 1618-1625
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper proposes a new real time virtual desired signal design method for improving the tracking characteristics to the actual desired signal. The augmented system comprising the already designed servo system is synthesized and the virtual desired signal is derived as a control input signal of the augmented system. Then the information of the servo system is used as a feedback signal in the virtual desired signal which is derived by considering the response of the designed servo system. It is also expanded to the preview virtual desired signal under the assumption that future signals of the desired signal and the disturbance signal are available. The proposed preview virtual desired signal has following characteristics.
A) preview virtual desired signal that cooperates the designed servo systems is derived using the information about that.
B) It can cope with the parameter errors and disturbances.
C) Both gain characteristics and phase characteristics are improved.
D) It can be added to the general servo system.
E) Its design is simple because the contol design parameter is only the weight of the virtual desired signal.View full abstractDownload PDF (1216K) -
Wennong ZHANG, Akihiko MATSUSHITA1995 Volume 31 Issue 10 Pages 1626-1634
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a practical design approach to m-input m-output plants of a given class which are characterized by a frequency-dependent uncertainty function around the transfer function of a stable and minimum-phase nominal model. The compensator includes a LPF (lowpass-filter) loop, which exhibits high gain in the low frequency-domain and low gain in the high frequency-domain. Hence, it can efficiently balance the trade-off between the problems of sensitivity and robust stability. We apply this type of compensator to control an electrical propelling caterpillar. The simulation and experimental results show the effectiveness and robustness of the controller.View full abstractDownload PDF (1370K) -
Takeshi HIROCHI, Masahiro YOKOMICHI, Masasuke SHIMA1995 Volume 31 Issue 10 Pages 1635-1642
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIf we apply the ordinary input-output linearization method to the “Ball and Plate System”, there appears singularity of the decoupling matrix at the origin. Due to this singularity, the control input diverges the origin. In order to solve this problem approximately, the approximate input-output linearization method proposed by Hauser et al. for nonlinear SISO systems is extened to MIMO system in this paper. It is shown under several applicable assumptions that the error and the state can be made bounded in the output tracking problem. Our method is applied to the “Ball and Plate System” for the case where the spin of the Ball is neglected. Two kinds of approximation method are proposed. Numerical simulations show the effectiveness of our method over the linear approximate approch.View full abstractDownload PDF (1104K) -
Toshiharu SUGIE, Kenji FUJIMOTO1995 Volume 31 Issue 10 Pages 1643-1649
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, taking the inverted pendulum as an example of nonlinear systems which are not exactly linearizable, we give a controller design method for the system based on the approximate linearization. In the method, we try to suppress the effect of the higher order residual terms in choosing the new coordinates for the approximate linearization. Furthermore, we show its effectiveness by experiments.View full abstractDownload PDF (1367K) -
I Cheol HWANG, Hirohisa NISHINO, Yoshito OHTA1995 Volume 31 Issue 10 Pages 1650-1657
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper derives a method to calculate the Hankel singular values of input time delay systems. The method uses the property that the gramian is an integral operator with a semi-seperable kernel function, and hence is represented as a Volterra operator plus a finite-dimensional operator. The Hankel singular values are obtained by calculating a transcendental equation involving the determinant of the associated finite-dimensional matrix functions. The relation between this result and the result in the literature is explained explicitly, by coordinate transformation. Futhermore, lower and upper bounds on their values are estabilished using the minimax properties of the eigenvalues for a compact and non-negative self-adjoint operator. This result shows that as the length of delay increases, all the Hankel singular values have a monotone increasing property.View full abstractDownload PDF (1595K) -
Suyu ZHANG, Koichi MIZUKAMI1995 Volume 31 Issue 10 Pages 1658-1665
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe problem of decentralized stabilization of a class of large-scale dynamical systems with time-varying delays in interconnections is considered. By making use of the Razumikhin-type theorem, we propose a class of decentralized state feedback controllers which can always guarantee uniform asymptotic stability of large-scale time-delay interconnected dynamical systems. In this paper, we only assume that the time-varying delays are any nonnegative continuous bounded functions. Furthermore, since the proposed decentralized state feedback controllers are independent of the delays, the results obtained in this paper are applicable to the systems without exact knowledge of the delays, i. e. the systems with perturbed delays. A numerical example is also given to demonstrate the validity of the results.View full abstractDownload PDF (1251K) -
Suguru ARIMOTO, V. PARRA-VEGA, Tomohide NANIWA1995 Volume 31 Issue 10 Pages 1666-1671
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSTwo kinds of hyper-stable servo controller without velocity measurement are proposed for a class of nonlinear mechanical systems. One is deduced from the passivity of mechanical systems between torque input and velocity output and the other is constructed from a hyper-stable connection called “compliant joint-connection”. The global asymptotic stability of setpoint control without velocity measurement as well as the asymptotic convergence of velocity estimation errors is implied conceptually by the framework of hyper-stability theory and proved rigorously from construction of Lyapunov's function. Further, it is shown that these controllers can be extended to cope with setpoint hybrid (position/force) control of robotic systems under geometric endpoint constraints.View full abstractDownload PDF (1366K) -
Takeshi HASHIMOTO, Shigehiro YAMAMOTO, Takehiko ASO, Minoru ABE1995 Volume 31 Issue 10 Pages 1672-1677
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe have proposed an autonomous navigation using fluorescent lamp array on the ceiling as a light house for vehicle motion, and discussed the computer simulation and experimental results of our primary method. As a next step, the vehicle control scheme based on the results of processing fluorescent lamp images using a personal computer is studied for more flexible navigation.
To realize the vehicle motion at a practical speed, the effect of image processing time on the deviation of vehicle track is examined by using computer simulations. As a result, it is possible to control the vehicle smoothly if the processing time is within 0.4 seconds.
A new method using the circumscribed rectangle of the fluorescent lamp image is adopted to detect the position and angle of the fluorescent lamp image on the screen. By this method, the position and angle information can be obtained more rapidly than Hough transformation.
Considering above discussions, an experimental vehicle system is constructed, and it is confirmed that the vehicle can be controlled to move under the fluorescent lamp array on the ceiling at a practical speed.View full abstractDownload PDF (2432K) -
Katsuhiko YAMADA, Shoji YOSHIKAWA1995 Volume 31 Issue 10 Pages 1678-1685
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a feed-forward control with a parameter identification law for an artificial satellite with antennas or manipulator arms. The proposed method utilizes the linearity of the unknown parameters on the angular momentum. It is possible to append an identification capability by adding a few terms to a conventional feed-forward control. This paper also proposes a compensation method for the time delay in the velocity control loop of the wheels and analyses its effects on the parameter identification results. The analytical results coincide well with simulation results and the effects of the time delay are expressed quantitatively.View full abstractDownload PDF (1179K) -
Yoshihide OKAMURA, Ikuya HOSHINO1995 Volume 31 Issue 10 Pages 1686-1694
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA new steering control system of aluminum hot rolling mills has been developed. The features of the new system are as follows:
(1) The steering process is stabilized by the state feedback control which adjusts bending force using the signal of rolling load difference.
(2) After stabilization of the steering process, an integrate feedback controller which adjusts roll gap difference using the signal of the steering sensor, is designed to reduce the steady-state steering deviation.
The effectiveness of the new system has been demonstrated by the application for a real plant.View full abstractDownload PDF (2224K) -
Koichi OSUKA, Tetsuhide OKA, Toshiro ONO1995 Volume 31 Issue 10 Pages 1695-1704
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we consider the control of biped robot with arms and head named Emu which we are going to develop. We especially focus on the stand-up and sit-down motion of Emu. In this paper, for the first step, we regard Emu as a simple but special 2 link time varying inverted pendulum, and we develop a control scheme which makes Emu can stand-up or sit-down at a low speed. We developed this control scheme in the following way. Firstly, we regard the parameters of the lower link except the mass such as the length and the moment of inertia as time-varying parameters which vary slowly. Then, we treat the system as a slowly varying system. With this consideration, we can consider the lower link is nearly equal to a link which consists of many moving links. Next, we design a non-linear control scheme for the frozen system which is obtained by considering the time-varying parameters as constant parameters. Furthermore using Lyapunov's theory, we confirm this non-linear control scheme is effective to the original slowly varying system, that is, to Emu. Finally, we developed a simple experimental system and through a certain simulation and an experiment we show the realizability of our method.View full abstractDownload PDF (2263K) -
Shuuji KAJITA, Kazuo TANI1995 Volume 31 Issue 10 Pages 1705-1714
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSAn experimental study of a biped robot is presented. A new scheme named “Linear Inverted Pendulum Mode” is utilized for controlling biped walking on rugged terrain. We developed a 6 d. o. f. biped robot “Meltran II” which has light weight legs and walks in a two dimensional vertical plane. After discussing the control systems for the support leg and the swing leg, we applied these control laws to the real robot and obtained following results.
1. Support phase dynamics of the biped robot under the proposed control law can be well represented by a linear model with a viscous term.
2. An adequate vertical speed at touchdown and a short duration of two-leg support after touchdown help smooth support leg exchange with a small loss of momentum.
Based on these results, a whole biped control system was implemented. In our experiment, biped walking with a half step period of 0.5-1.0s and a half stride of 10-14cm was realized on a flat floor. The maximum walking speed was 24cm/s. Our robot also walked over a box of 3.5cm height at a speed of 20cm/s.View full abstractDownload PDF (2583K) -
Hiroshi HASHIMOTO, Minoru HIGASHIGUCHI1995 Volume 31 Issue 10 Pages 1715-1721
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a new algorithm to solve the polynomial Diophantine equation (DE); A(s)X(s)+B(s)Y(s)=C(s), which plays the key role in the design of the feedback control systems. The proposed algorithm (PA), which is based on the backward substitution, consists of the simple algorithm. Comparing the previous ones, it is shown through the theoretical considerations that PA has two advantages. The first is the high freedom of the degree associated with a given polynomial and the solution. The second is that the amount of the operation number, in the sense of arithmetic operation, of PA is remarkable reduced. Furthermore, it is shown that the applying PA to the polynomial matrix DE is easy under suitable conditions.View full abstractDownload PDF (1067K) -
Atsushi OHTA, Toshiyuki OHBA, Tomiji HISAMURA1995 Volume 31 Issue 10 Pages 1722-1729
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSLiveness is one of the most important properties in Petri net analysis, which assures fireability of every transition in the net and avoidance of deadlocks. In this paper we discuss the liveness of extended subclasses of Petri net, i. e. strongly connected marked graphs and strongly connected state machines (SCSM) in which permission or inhibitor arcs are added in restricted structures. The additions of these arcs facilitate modeling of practical discrete event systems by the net. The necessary and/or sufficient conditions for liveness are derived for above subclasses. Then the computational complexities to verify liveness of these nets are discussed and it is shown that liveness of the above subclasses can be verified in deterministic polynomial time by the applications of the obtained criteria.View full abstractDownload PDF (1637K) -
Fuminori IKEMOTO, Hirosi KAWAKAMI, Tadataka KONISHI1995 Volume 31 Issue 10 Pages 1730-1738
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA method for creating candidates for conceptual design of physical systems is proposed for the purpose of supporting conceptual design by using computer. In this method, fragmentary knowledge of functional composition acquired from existing objects are organized into candidates for design solution, so called “functional diagram” in Value Engineering. Excellent candidates are searched out from the huge number of combinations of the above mentioned knowledge within a practical short time based on Genetic Algorithm.View full abstractDownload PDF (4475K) -
Noriyasu HONMA, Mitsuo SATO, Kenichi ABE, Hiroshi TAKEDA1995 Volume 31 Issue 10 Pages 1739-1745
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe paper demonstrates that holon networks can be used effectively for the identification of nonlinear dynamical systems. The emphasis of the paper is on modeling of complicated systems which have a great deal of uncertainty and unknown interactions between their elements and parameters.
The concept of applying a quantitative model building, for example, to environmental or ecological systems is not new. In a previous paper we presented a holon network model as an another alternative to quantitative modeling. Holon networks have a hierarchical construction where each level of hierarchy consists of networks with reciprocal actions among their elements. The networks are able to evolve by self-organizing their structure and adapt their parameters to environments. This was achived by an autonomous decentralized adaptation method.
Holon networks, being constructed by a number of elements and hence having high degree of parameter freedom, have great flexibility of their functions. But, at the same time, such networks are computationally expensive.
In this paper we propose a new emergent evolution method to reduce the computation times. In this new evolution method the initial holon networks consists of only a few elements and it grows gradually with each new observation and autonomous criterion in order to fit their function to the environment. Some examples show that this method can lead to network structures which have sufficient flexibility and adapt well to various environments.View full abstractDownload PDF (1470K) -
Koichi YAMADA1995 Volume 31 Issue 10 Pages 1746-1753
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper proposes a method for diagnostic problem-solving with fuzzy abductive reasoning. Diagnosis is considered as a process to derive a set of hypotheses that explains the observed symptoms using the causal relationship from causes to symptoms. This process of inference is called abduction. The observed symptoms frequently include vagueness or fuzziness in their degrees of occurrence. Therefore, fuzzy abduction introducing the fuzzy theory might be effective for diagnoses. However, in diagnoses in the real world, it is risky to assume that operators can find all of the symptoms. They may fail to find some symptoms. In such cases, the conventional fuzzy abduction sometimes fails to obtain the solutions, because it tries to find causes that are the complete explanation of the given symptoms. In this paper, we introduce the concept of “cover” to cope with the problem, and expand the fuzzy abduction with it. The new idea is to find a set of causes that “covers” the observed symptoms, not that derives the symptoms exactly. We then apply the expanded fuzzy abduction to a diagnostic problem of a diesel engine for ships, and confirm its usefulness. Furthermore, we compare the fuzzy abduction with another approach, the inverse problem of fuzzy relational equation, which has been used to infer causes from observed symptoms.View full abstractDownload PDF (1171K) -
Seiichi YOSHIMURA, Kenichi TAKANO, Kunihide SASOU1995 Volume 31 Issue 10 Pages 1754-1761
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSOperating environment in huge systems like nuclear power plants or airplanes is changing rapidly with the advance of computer technology. It is necessary to elucidate thinking process of operators and decision-making process of an operator team in abnormal situations, in order to prevent human errors under such environment. The Central Research Institute of Electric Power Industry is promoting a research project to establish human error prevention countermeasures by modeling and simulating the thinking process of operators and decision-making process of an operator team.
In the previous paper, application of multilevel flow modeling was proposed to a mental model which conducts future prediction and cause identification, and the characteristics were verified by experienced plant operators.
In this paper, an operator team behavior model and a fundamental operator's thinking mechanism especially “situation understanding” are proposed, and the proposals are evaluated by experiments using a fullscale simulator. The results reveal that some assumptions such as “communication is done between a leader and a follower” are almost appropriate and that the situation understanding can be represented by “probable candidates for cause, determination of a parameter which changes when an event occures, determination of parameters which are influenced by the change of the previous parameter, determination of a principal parameter and future prediction of the principal parameter”.View full abstractDownload PDF (1536K) -
Noboru NOGUCHI, Hideo TERAO1995 Volume 31 Issue 10 Pages 1762-1768
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSTo solve the problem of lack of labor and decrease of skilled workers for agriculture and construction industry, we propose the method of creating work schedule for some industrial robots which perform their respective task simultaneously. For obtaining suboptimal feasible solution of the problem which includes two combinational problems, a layered genetic algorithm (LGA) is contrived. The LGA is able to solve the two combinational problems with relevance without increase of calculating load.
In this paper, we consider an agricultural production system, that is, hay transportation on slope by using two transporting robots and a loading robot. Work schedule for two transporting robots is optimized in the upper layer of the LGA, while work schedule of the loading robot is optimized in the lower layer which is constrained by the upper layer. The proposed method can create work schedule under not only single objective function such as work or work time, but also multi-objective function considering both of them. The schedule made by LGA under the objective function of work can reduce work by up to 56% compared to randomly scheduled situation. The effectiveness of this method is assured by comparing the results with the schedule made by a man with experience of hay transportation. As the quality of the schedule by this method is almost equal to that made by a man with experience, it is also possible to evaluate the ability of workers from the aspect of work efficiency. Finally, we discuss the human decision mechanism on scheduling by identifying the weighting factors for work and work time in multi-objective function.View full abstractDownload PDF (2573K) -
Hiroshi NOBORIO1995 Volume 31 Issue 10 Pages 1769-1777
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we propose a functional extension of the previous sufficient condition to design a larger family of sensor-based path-planning algorithms running in an uncertain world. In previous sensor-based path-planning algorithms, an automaton basically goes straight to its goal, and if the behavior is interfered by an unknown obstacle, the automaton avoids the obstacle by the clockwise or counter-clockwise order. Then the automaton goes straight to the goal again after leaving the obstacle from an arbitrary point which comes close to the goal asymptotically based on the Euclidean distance. This is the previous sufficient condition for keeping the deadlock-free characteristic in the sensor-based path-planning. This paper generalizes the sufficient condition by replacing the Euclidean distance with different types of distances toward the goal. By using an arbitrary distance function flexibly, we get a wider set of sensor-based path-planning algorithms. As an example of them, we show a learning sensor-based path-planning algorithm based on adaptive fitting between the distance function and world shape by sequential tests from the start. By the adaptive fitting, the functional learning algorithm (FLA) makes a shorter deadlock-free path in almost all worlds. Finally the goodness of the learning algorithm and the superiority of the new sufficient condition are ascertained in a graphics simulation.View full abstractDownload PDF (5052K) -
Makoto NAKAMURA, Yoshiro SAKAI, Masakatsu FUJIMOTO, Itsuo TAKANAMI1995 Volume 31 Issue 10 Pages 1778-1786
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn the present paper, a dryness prediction model for commercial use is proposed for reducing human power and for higher quality. The proper dryness to be provided to a particular raw material is predicted before drying. And based on that proper dryness, necessary drying time in a suitable set of drying conditions is also predicted. The model for predicting dryness is built as a fuzzy linguistic model using weight or fatness and desirable hardness of product as the IF-part variables and relative weight of product as a THEN-part variable. One of the major advantages of the present system is that it needs relatively small number of rules, to be concrete, only nine rules. This idea for reducing fuzzy rules can be applicable to other systems. A multiple regression analysis model is employed for predicting necessary drying time, using nature of material, dryness predicted by the above fuzzy model, and drying conditions applied as variables.
Simulations and experiments showed very good coincidence.View full abstractDownload PDF (1577K) -
Yoshitomo OKADA, Tsuyoshi YAGI, Sakae SHINOMIYA1995 Volume 31 Issue 10 Pages 1787-1789
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents the fundamental acceleration response characteristics of a measuring device of angular acceleration. Moreover, the calibration method of the angular acceleration of this device is presented, and an applied example of this device is offered.View full abstractDownload PDF (360K) -
Wataru KASE1995 Volume 31 Issue 10 Pages 1790-1792
Published: October 31, 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this note, we re-examine a solution of H∞ controi problem presented in terms of polynomial matrix using state space representation. It is shown that positive semi definiteness of the solution of Riccati equation is not used in the polynomial approach.View full abstractDownload PDF (269K) -
1995 Volume 31 Issue 10 Pages e1
Published: 1995
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (97K)
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