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Volume 19, Issue 8
Displaying 1-13 of 13 articles from this issue
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Takahiro MATSUMOTO, Masao IKEDA1983 Volume 19 Issue 8 Pages 601-606
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSStructural controllability of a linear time-invariant system is considered using the representation called an intermediate standard form (ISF), descriptor form, or semistate equation. This unorthodox representation is employed instead of the ordinary state equation to express structure of physical systems in their mathematical descriptions in a straight-forward manner so that a major drawback in the structural consideration using state equations is resolved. As a definition, a system is said to be structurally controllable if its state equation, which can be obtained from the ISF representation, is controllable for almost all nonzero parameters in the ISF. The necessary and sufficient condition for structural controllability is presented both in algebraic and graph-theoretic terms, which is applied to ISF.View full abstractDownload PDF (751K) -
Masatoshi NAKAMURA1983 Volume 19 Issue 8 Pages 607-613
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSPreviously we derived an exponential weighted least squares method (EWLS) for linear stochastic dynamic systems. A remarkable feature of this derivation was the introduction of an index λ into the least squares criterion to process effects of noises in the systems. The EWLS does not require any knowledge of the noise covariance matrices and the characteristics of the EWLS can be regulated by the index λ. In a number of practical situations, the EWLS can be used effectively for the estimation of the state variables of systems where it is difficult to identify the noise covariance matrices. The primary motivation for this research was to extend the use of the EWLS to nonlinear stochastic systems.
In this paper, we first derives an EWLS for nonlinear stochastic systems. Next, we find a correspondence between the EWLS and nonlinear filters such as the extended Kalman filter, the stochastic linearization filter and the second order filter. Finally, we propose an iterative algorithm of the EWLS to improve estimation accuracy. This algorithm is proved to be an extention of the Gauss-Newton method for the estimation of constant parameters.View full abstractDownload PDF (935K) -
Katsutoshi TAMURA, Katsuhiko KAWAI1983 Volume 19 Issue 8 Pages 614-621
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper we discuss a model reference adaptive control system for single-input, single-output linear discrete-time plant. It is assumed that the plant has unknown and time-varying parameters and that ramp-wise waveform disturbances are imposed on the plant. The observability condition of the state and the disturbance is examined, the minimum time state and disturbance observer is given, the controller for the model reference control is presented, and the minimum time parameter identifier is shown. The adaptive control system using the observer, the controller and the identifier is obtained. Numerical examples are given to illustrate the effectiveness of the adaptive control system.View full abstractDownload PDF (830K) -
Toshihiko YAMAWAKI, Taikyu KIM, Hiromitsu KASHIWAGI, Toshio KOBAYASHI1983 Volume 19 Issue 8 Pages 622-627
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper showes that conventional z transform of time functions is not an extention of one of number sequences, and reformulates z transform pair to such an integral transformation that converts impulse train to power series of z-1.
Applying new z transform to sampled-data systems, it is convenient to make preliminary introduction for a double transformation made from ideal sampling and z transform. The double transformation, named here sz transform, not only corresponds to conventional z transform, but also has the following features.
(1) sz transform can analyse exactly such sampled-data systems in which the input of sampler jumps at sampling instants.
(2) sz transform plays the same role as modified z transform.View full abstractDownload PDF (757K) -
Toshihisa AOKI, Shigeyuki HOSOE, Yoshikazu HAYAKAWA1983 Volume 19 Issue 8 Pages 628-635
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA necessary and sufficient condition is derived for the structural controllability for systems described by the following descriptor form
Kx=Ax+Bu
The descriptor form representation of systems has an advantage that it can reflect physical structure of real systems more directly than using usual state-space form.
The condition for the structural controllability is represented by means of Coates graph g[A B] and g[M N], where [M N] denotes a structured matrix which is uniquely determined by K, A, B.View full abstractDownload PDF (1114K) -
Shushan BAI, Takahiko TSUJISAWA, Ryozaburo TAGAWA1983 Volume 19 Issue 8 Pages 636-641
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we propose a new design method of the low sensitive electric-servo system with the wide load change.
From the three points shown below, this method has the essential differences from the conventional method.
1. It is based on the concept of obtaining the low sensitive dominant poles and zeros.
2. The model is not used at all.
3. The sensitivity function is not used explicitly.
By applying the Utmost Compensation Type Controllor of 1-type to speed control loop which is constructed inside the position control system firstly, the low sensitive dominant pole and zero mentioned above is realized in this method.
The feature of this method is that, by extending the band width of speed control loop and fixing the zero frequency gain, both of the low sensitivity and stability are achievable simultaneously.View full abstractDownload PDF (761K) -
Kaname YOSHIDA1983 Volume 19 Issue 8 Pages 642-649
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper attempts to obtain an approximate optimum of the geometric programming (GP) problem. Generally speaking, until now, a lot of algorithms of GP have been proposed to obtain the optimum and the optimal solution and those methods need fairly much works to obtain ones.
On the other hand, there is a case that the true optimum or the true solution are not neccessarily needed, but only the approximate ones are needed. For the example, the combinatorial problem is one of the examples, where the approximate optimum of an alternative problem is used to estimate whether the alternative one is selected or not. As another example, when the problem has multi-local solutions, we need to compare each local solution to the others. As the above examples, if the approximate optimum can be easily obtained, the calculation volume to select the optimal alternative or solution will fairly decrease.
In this paper, we introduce some parameters to the primal problem to recast it into the set of the smaller-scale problems with the zero degree of difficulty. The degree of difficulty is the term to measure the calculation volume to solve the dual problem. The parameters are used to share the given problem into several ones that each of them has not all the polynomial terms and only the part of the polynomials in the given original problem. The shared, if possible, problem is easily solved by treating only the linear equations, because the degree of difficulty of the problem is zero. Moreover the sufficient conditions for the feasibility of the shared problem and the relation between the original problem and the shared ones are shown. From the optimums of the shared problems, the lower band for the optimum of the original problem is shown. To illustlate the results, some numerical examples are calculated.View full abstractDownload PDF (852K) -
An Artificial Eye of Intelligent VehicleTakeshi HIROSE1983 Volume 19 Issue 8 Pages 650-656
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper describes an obstacle recognition method and its experimental results acquired from newly designed equipment called a road pattern recognition unit. This unit functions as artificial eyes of intelligent vehicle to locate obstacles in front of it. The unit consists of a pair of TV cameras and their video signal processing device. Each TV camera is fixed apart perpendiculaly on the front part of the vehicle that these two cameras' lines of sight may cross at a distance ahead of the vehicle.
The obstacles can be recognized as follows; To extract profiles of obstacle images, the video output signals are differentiated and thereby two sets of image's edge signals are obtained from the upper and the lower cameras. In order to determine presence of obstacles, signal matchings between the upper and the lower image's edge signals are searched. However, shadows or painted lines on the road surface and accidental signal matchings are likewise recognized as obstacles themselves. These erroneous recognitions were tried to be eliminated by utilizing characterization technique of obstacles from their dimensions and locations.
Test course experiments were carried out on an unit equipped automobile and its detecting actions were successfully performed against other automobile and rubber cones in the street. This road pattern recognition unit have proven to recognize horizontally located obstacles at a distance of 9 meters ahead of the vehicle within 1/30sec.View full abstractDownload PDF (4394K) -
Takao YAMAGUCHI, Kiyohiko FUJITA1983 Volume 19 Issue 8 Pages 657-664
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSEffect of Stray Light on Spectral Emissivity Measurements
In order to determine the true temperature from the measured color temperature, it is-required to determine the wavelength dependency of the spectral emissivity of a given object. Measurement applying an apparatus with a monochromator and a photomultiplier combined brings about the value of the spectral radiance multiplied by the apparatus factor, the coefficient and constant of measurement, and by others. Then, the relative spectral radiance is determined by dividing the spectral radiance measured in the various wavelengths by that in a certain wavelength λ0, so that the relative spectral property co-efficient of the apparatus is determined, and the coefficient and constant of measurement are eliminated.
Next, as it was found out that the stray light in a monochromator has great effects on the measured value, the stray light degree is defined, the method of determining it is proposed, and the stray light effects on the spectral emissivity measurement are examined.
Consequently, it is obvious that a monochromator with the stray light degree 10-7 and below is to be applied and that a double-monochromator complies with this requirement. Thus, the method mentioned above is checked up to be appropriate by measuring spectral emissivity in visible region in the case of pure iron at 1200°C, using a double-monochromator with the stray light degree 10-8. And in this case, the spectral emissivity is in an approximately linear relationship with the wavelength.View full abstractDownload PDF (1215K) -
Makoto YOSHIZAWA, Hiroshi TAKEDA1983 Volume 19 Issue 8 Pages 665-672
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a new interpretation of the human operator's compensation mechanism for time-delay in a compensatory manual control system in terms of the finite pole assignment. In the open-loop characteristics of the operator in some compensatory tracking tasks to a random step input, each gain curve has peaks at relatively high frequencies. This phenomenon can be explained as a feature caused by the finite pole assignment method which the operator uses implicitly in order to compensate his own time-delay because there are peaks in the open-loop gain curve of the system with time-delay to which the finite pole assignment method is applied. Hence, a state equation model representing operator's transient response to a step-like input is proposed from the viewpoint of the finite pole assignment. This model contains an observer estimating the state of a controlled object and predictor of time-delay.View full abstractDownload PDF (1092K) -
Hiroshi MURATA1983 Volume 19 Issue 8 Pages 673-675
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (403K) -
Masanori KUWAHARA1983 Volume 19 Issue 8 Pages 676-678
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (361K) -
Yasushi ISHII1983 Volume 19 Issue 8 Pages 679-681
Published: August 30, 1983
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (336K)
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