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Volume 13 (1977)
- Issue 6 Pages 533-
- Issue 5 Pages 425-
- Issue 4 Pages 313-
- Issue 3 Pages 209-
- Issue 2 Pages 105-
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Volume 13, Issue 4
Displaying 1-19 of 19 articles from this issue
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Toshimitsu NISHIMURA1977 Volume 13 Issue 4 Pages 313-317
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe square-root method is applied to the LQG problem that derives the optimal estimate and control using a quadratic performance index in large-scale linear systems.
First a square-root solution of the regulator problem similar to that for the Kalman filter is derived. Then it is combined with the square-root solution of the estimation problem and a unified approach to the LQG problem is presented. By means of this square-root scheme, significant enhancement of accuracy in numerical computation is expected and the stability of the solution of Riccati type equations in estimation and control problems will be guaranteed.View full abstractDownload PDF (583K) -
Kazuo YAMANAKA, Kenko UCHIDA, Etsujiro SHIMEMURA1977 Volume 13 Issue 4 Pages 318-323
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn a stochastic linear composite system, which is composed of several subsystems, it may be desired to obtain an estimate of the state of only one particular subsystem. A usual approach to this problem will be to construct a Kalman-Bucy filter for the total system, and to obtain the required partial state estimate as a part of the total one. That is, a dynamical filter of the same dimension as that of the total system is necessary for only the partial state estimation. From the computational view point, it is preferable to obtain a partial estimate by a suitable dynamical filter, which is not necessarily optimal, of the dimension of that subsystem. In this paper, we consider a class of composite systems in which two subsystems are coupled and their time responses are widely different. And we propose a method to synthesize an approximate filter for the “slower” subsystem. It is also shown that the approximation error vanishes as the ratio of the maximum eigenvalue of the “slower” subsystem to the minimum eigenvalue of the “faster” subsystem approaches to zero.View full abstractDownload PDF (720K) -
Nobuhide SUDA, Akio ENOKI1977 Volume 13 Issue 4 Pages 324-329
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe present paper proposes a new matrix representation of bond graphs of which the arrows on bonds have already been assigned. This matrix representation is different from the one used by Ort and others. The relation between the full rank properties of the matrices and the structure of bond graph is studied, which provides us with a simple method of checking if a bond graph contains any redundant internal bonds. We define the equivalence condition by using the fundamental matrices and give the adequate condition for assigning the arrows. Adequate way of assigning the arrows on bonds is in general not unique. It is proved that all the adequate ways of assigning ones give equivalent results.View full abstractDownload PDF (794K) -
Juichi MIYAMICHI1977 Volume 13 Issue 4 Pages 330-335
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe discrete control is widely found in various field, including those related to the control problem by digital computers. Systems whose control inputs are restricted to discrete values are called the quantized control systems.
A state x is reachable if there is an input sequence which carries the system from zero to x. A state x is controllable if there is an input sequence which carries the system from x to zero. An adjective “almost” will be used if the above is true not exactly but within any degree of accuracy.
In this paper, some of the properties concerning the controllability of the system which are true for the systems controlled by continuous level inputs are examined for quantized control systems. The systems under discussion here are linear, constant and discrete-time dynamical systems over the field of real numbers whose control inputs are restricted to the integer vectors:
x(k+1)=Ax(k)+Bu(k)where x(k)∈Rn, u(k)∈Zm and A and B are real matrices.
The main results are as follows:
(1) The set of all controllable states H∞ has a structure of Z-module which spans the subspace of all controllable states by continuous level inputs.
(2) Under the finiteness condition that the set of all reachable states M∞ is a finitely generated Z-module, H∞ is A-invariant and every reachable state is controllable.
(3) The set of all “almost controllable” states is A-invariant but without some finiteness condition it is not a Z-module.
(4) (Without any conditions) Every “almost reachable” state is “almost controllable” and if the system is “almost reachable” we can send the system from any initial state to any final state within any degree of accuracy.View full abstractDownload PDF (936K) -
Yoshifumi SUNAHARA, Shin-ichi AIHARA, Fumio KOJIMA1977 Volume 13 Issue 4 Pages 336-343
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe purpose of this paper is to present a filtering technique for distributed parameter systems with random coefficients. Two kinds of systems are considered. One is modeled by a partial differential equation of parabolic type and the other by that of hyperbolic type. In the both systems, the statistics of random coefficients are assumed to be white Gaussian.
Based on the concept of stochastic eigenvalue problems, properties of the solution processes to the system equations are first discussed. Then, the Radon-Nikodym derivative is given which plays an important role to derive the filtering equation. Under the criterion of the minimal variance estimate, a precise form of the filter dynamics is derived, reflecting the nonlinearity due to the existence of random coefficients.
The latter half of this paper is devoted to describe an approximated filter dynamics by the Gaussian assumption, and to show results of digital simulation experiments.View full abstractDownload PDF (887K) -
Takashi SOEDA, Hirokazu ISHIHARA1977 Volume 13 Issue 4 Pages 344-350
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper concerns with both the system identification problem based on the environmental data and the prediction problem of the identified system state by Kalman filtering method. Furthermore, it is shown that this method can be applied to the selection of the observation sensor locations. These methods are tested by the data measured in Osaka city.
A kind of lower order model is made by applying the factor analysis to the multiple linear regression model constructed by the actual data. Kalman filtering prediction algorithm with the correlation between the system noise and the observation noise is used to predict the state of this lower order model and the state of the original model. We describe the cases when the statistics of the observation noise is known or unknown. The accuracy of the prediction presented above is compared with the persistence model by numerical examples.View full abstractDownload PDF (956K) -
Hiroyuki TAMURA, Tadashi KONDO1977 Volume 13 Issue 4 Pages 351-357
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a revised GMDH (Group Method of Data Handling) algorithm, which selects optimal partial polynomials in each selection layer, is developed. In the previous GMDH algorithms, the structure of the partial polynomials is fixed by a predetermined description for all possible combinations of two variables, therefore the partial polynomials obtained are not always optimal regression equation. The revised GMDH algorithm in this paper generates in each selection layer an optimal partial polynomial which minimizes the mean square error for the checking date, and polynomials as such are used to construct the multilayered structure. The revised GMDH algorithm is applied to the identification problem of a largespatial pattern of air pollution and the result obtained is compared with that by the basic GMDH algorithm.View full abstractDownload PDF (825K) -
Masahiko ONDA, Satomi SUZUKI, Yasujiro OSHIMA1977 Volume 13 Issue 4 Pages 358-364
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper we discuss the time optimal control problem of an electrohydraulic servo system. This system is described by the 16th order nonlinear ordinary differential equations with multi-discontinuities. The control variables are inputs to the two servovalves with different nonlinear flow gains and dynamics. The performance index to be minimized is made up of integrated square errors of allowable system pressures, load displacement and velocity around the origin, and response time.
This problem is solved by applying a hillclimbing algorithm to the 4th order Runge-Kutta method simulation of the state equations. As the pattern of this control is bang-bang, it is important to find the switching criteria as well as stability conditions. In this numericall experiment, a square root function is taken as closing control to a valve, and the amplitude of a feedback variable is limited to ensure reasonable stability.
In spite of the several assumptions made throughout with the system, such that the valve dynamics is simple and the liquid flow is steady, the computational results have shown fairly good coincidence with the experimental results.View full abstractDownload PDF (844K) -
Tatsuo KITAJIMA1977 Volume 13 Issue 4 Pages 365-369
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper is concerned with improvement of the convergence rate of the computational algorithm using series expansion for the inverse operator of a positive-definite operator.
The fundamental operator polynomial Pm(A) is introduced, which is based on the first m-terms of the series expansion of the inverse of the Hessian of a quadratic performance index. By computing the operator polynomial Pm(Ai) at each iteration, a new computational algorithm is developed and the ratio of convergence for this algorithm is discussed.
This series expansion technique can also be applied to some optimal problem with constraints.View full abstractDownload PDF (605K) -
Hideo HANAFUSA, Haruhiko ASADA1977 Volume 13 Issue 4 Pages 370-377
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn general, robot hands in industrial uses have specifically designed fingers corresponding to the shapes of work pieces to be handled. However, the more versatile hands are desirable in case of advanced jobs such as assembly process, because various types of mechanical parts must be handled.
This paper describes the design and control problem of universal robot hand which has elastic fingers and can grip various workpieces at the proper position suitable for their shapes. We propose an adaptive prehension system which consists of a newly designed universal hand, an ITV camera and a mini-computer. The universal robot hand has three elastic fingers which are driven by pulse motors through coil springs.
We discuss the adaptive prehension process by the above robot system. The workpieces are caught by the ITV camera and the data of the peripheral shapes are sent to the mini-computer. The computer determines the finger arrangement at the stable prehension based on the potential function theory of prehension system, which we've ever introduced as an criterion of stability. An effective and simple computation algorithm is proposed to meet an on-line use of the robot in. the industrial application. The experiment verified the usefulness of the developed system.View full abstractDownload PDF (2250K) -
Morihiro MATSUTA, Kanji KITO1977 Volume 13 Issue 4 Pages 378-383
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSMeasurement of gas temperature in an internal combustion engine is very important for studying the combustion process. The measurement is, however, difficult and many methods, so far reported, are almost always tested in laboratories and have difficulties for practical application.
In the present study, a method for the temperature measurement by measuring the radiance of CO2-4.3μm band (CO2-4.3μm band radiance method) is proposed and experimentally investigated for the accuracy and precision. The method has been found to be applicable for measuring the gas temperature in practical engines.
The main findings are as follows.
(1) Spectral emissivity of CO2-4.3μm band, calculated from the statistical model, coincides with that experimentally obtained. It depends on the optical path length, total gas pressure, and CO2 concentration or partial pressure. The combustion gas, therefore, can not always be regarded as a blackbody even under high CO2 concentration.
(2) The radiance-temperature calibration curves for the combustion gas can be obtained by calculation.
(3) The calibration curves also depend on the optical path length, total gas pressure, and CO2 concentration. However, if the measurement is restricted to the gas in internal combustion engines and 2∼3% error is allowed for temperature calibration, the calibration curves can be regarded to depend only on the optical path length.
(4) It has been experimentally clarified that the engine gas temperature can be measured within ±10% accuracy.
(5) The method provides useful temperature information in an internal combustion engine, informative to the analysis of the combustion process.View full abstractDownload PDF (1342K) -
Theoretical and Experimental Estimation of the Systematic ErrorsSusumu HATTORI1977 Volume 13 Issue 4 Pages 384-389
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe realization of the IPTS above 1337.58K is affected by several factors producing systematic errors. In this paper, the effects of the error factors associating directly with the multiplicative comparator of spectral radiances are theoretically discussed and experimentally investigated.
As the results, the accuracy of the comparator is estimated to be ±0.01% in transferring to the strip lamp the spectral radiance of the blackbody at the gold point and better than ±0.01% in multiplying the spectral radiance by the factor of two.View full abstractDownload PDF (808K) -
Minoru INAMURA, Hiromichi TOYOTA, Yukio HIRANAKA, Toyohiko KASHIWAGI1977 Volume 13 Issue 4 Pages 390-393
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe total effective emissivity in the thermal infrared radiation region has been measured by different methods; 1) using radiometers, 2) calculating from the data obtained by spectral reflection measurements, 3) measuring the intensities of polarized lights, and 4) measuring the heat losses. The methods 1) and 2) are most popular ones, but they need a reference surface, of which the emissivity must be precisely known, and over which the temperature uniformity must be maintained since it affects the precision of measurement. The method 3) cannot be applied to any surface (successful only for an ideally radiating surface). The method 4) is a fundamental one. But until now it has been unpopular, because it is time-consuming and it needs physical values, such as the specific heat and the radiating area of the surface.
However, the present demand for the temperature control of spacecrafts has made the method 4) practically important. For a standardimplementation it requires a special vessel containing high vacuum air (thinner than 10-5 Torr), composed of low temperature walls (cooled by liquid nitrogen or other coolants), in which samples are placed. The apparatus becomes too large for this method to be used popularly.
Taking into consideration the present status of affairs, the authors obtained satisfactory values of effective emissivity for practical use, even in a low vacuum and in the standard atomosphere, the surrounding being kept at the normal room temperature.The authors' success may make the method 4) which theoretically has a high precision, more popular in measuring the emissivity.View full abstractDownload PDF (1045K) -
Design of Reflectionless Multiple Junction SystemsMuneyuki YOSHIOKA, Yoshinobu MORIKAWA1977 Volume 13 Issue 4 Pages 394-399
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper deals with the reflectionless matching technique in fluidic networks.
On the basis of the theory of distributed parameter circuits, the perfect matching conditions in branched transmission line systems are introduced. Then, these conditions are reduced to the practical matching conditions in pneumatic systems.
The practical matching conditions in branched pneumatic transmission line systems can be summarized as follows.
(1) At the terminals, the transmission line must be loaded with its characteristic resistance.
(2) At the junctions, the total area of the cross sections of branching line must be equal to the cross sectional area of the main line.
Examples of matched transmission line systems and their theoretical and experimental responses to step inputs are presented to show the usefulness of this matching technique.View full abstractDownload PDF (1599K) -
Consideration with Two-Dimensional Flow ModelTakashi MATSUI, Hisaharu TAKAI1977 Volume 13 Issue 4 Pages 400-405
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSAn annular jet proximity sensor sometimes exhibits instabilities if it is not well designed. In the previous paper, we indicated that the instabilities are caused by the negative resistance in the output characteristics of the sensor. In this paper, the output characteristics are analytically derived. In the analysis, a two-dimensional flow model is used to simplify the analysis instead of an annular jet model, and the theory for two-dimensional reattaching jet flow by Bourque & Newman is modified and applied. As a consequence, it is analytically shown that the negative resistance appears in the two-dimensional model, and that the cause of negative resistance is explained as follows.
Since the main jet deflects outward with increasing the output flow, the reflected jet flow returned into a cavity decreases, and, moreover, the average dynamic pressure of the reflected jet which impinges on the output port decreases. Consequently, the rise of output pressure affected by the dynamic pressure of the reflected jet reduces with increasing the output flow. This is the cause of negative resistance. On the other, hand, the cavity pressure as well as the resistance at the output port generates a positive resistance in the output characteristics. The negative resistance is apt to appear in the neighborhood of zero output flow, because the resistance of output port is small in that region. The experimental results with two-dimensional models are found to be in qualitative agreement with the theoretical results.View full abstractDownload PDF (814K) -
Tsutomu YOKOZUKA1977 Volume 13 Issue 4 Pages 406-413
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper describes the use of digital computer techniques for the identification of equivalent circuit parameters of capacitor motors from the measured data, and the extension of this technique to the analysis of the plain single-phase induction motors. The problem of the optimization of parameter determination, the correcting factor K and repeating number n, are discussed. Based on these techniques, parameters are obtained on several capacitor motors. Using these parameters, various characteristics such as 2-phase excitation, capacitor drive, DC braking-torque, accelerating performance etc. are computed and compared with experimental results.View full abstractDownload PDF (945K) -
Hisaichi IRIE1977 Volume 13 Issue 4 Pages 414-417
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe thyristor chopper combined with a constant voltage power supply, such as battery, is widely used as a high efficiency variable D-C power source for D-C motor control. The stepup chopper for regenerative braking is used together with a step-down chopper for drive, in order to obtain faster deceleration of the motor and higher efficiency of the system.
This paper deals with the characteristics of the separately excited D-C motor regeneratively braked by a step-up chopper and a D-C power sink. The characteristics of the motor being braked are calculated, in the same manner as with it being driven. In the calculation of a braked motor, the armature voltage in the motor's driven state is replaced by the difference between the sink voltage and the armature voltage. Also the speed voltage is replaced by the sink voltage minus the speed voltage. The similarities between the characteristics of the motor being driven and those being regeneratively braked are confirmed by the equivalent circuits, by the voltage and current waveforms and by the load characteristics with experimental results.View full abstractDownload PDF (456K) -
Tsunehiro MUNAKATA, Yoshio HAYASHI1977 Volume 13 Issue 4 Pages 418-419
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (275K) -
Jun IKEBE, Michio OHTA, Nagao ORIGUCHI1977 Volume 13 Issue 4 Pages 420-421
Published: August 30, 1977
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (389K)
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