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Volume 30, Issue 1
Displaying 1-19 of 19 articles from this issue
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Yoshinari MIZUTANI, Yoshinori OGATA, Toshimitsu TAKAHASHI, Satoshi SAI ...1994 Volume 30 Issue 1 Pages 1-8
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe have investigated dynamics of single neuronal spontaneous activities in the mesencephalic reticular formation (MRF) of a cat in natural outdoors, using a telemetry system that could measure 7 channels of physiological signals, such as neuronal activity, electroencephalogram, electrooculogram, electromyo gram, and so on. The telemetry system transmits the signals by the method of PDM/FM with about 88MHz of main carrier. We have successfully recorded long-term spike trains of several single neurons in the MRF. Spectral analyses were carried out on the time series of counts converted from the spike train. The spectrum during waking state outdoors showed a spectral density approximately inversely proportional to frequency (1/f-like spectrum) in the frequency range of 0.01-1.0Hz. The 1/f-like spectral characteristic during waking state was similar to the one during paradoxical sleep, but clearly different from the white-noise-like spectral profile during slow wave sleep. The 1/f-like spectra observed in the MRF neuronal activities outdoors probably suggest that the neuronal activity displays slow fluctuations both by inputs from the internal/external environments and by dynamics of the MRF neuronal network.View full abstractDownload PDF (2050K) -
Yoshiharu MASUDA, Bunjiro ICHIJO, Michihiko FUJII1994 Volume 30 Issue 1 Pages 9-15
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSRecently in the field of agriculture, demands for convenient measurement of water contents in rockwool and sand, concentration of nutrient solution, and plant physiological information with the change of environments, are increasing. This paper shows the characteristics and applications of resistance-capacitance meter composed of two resonant circuits, which is developed to solve these problems. By this resistance-capacitance meter, capacitance and resistance of specimen can be measured by both zero method and deflection method, and small changes in resistance can be measured by deflection method. Measurement sensitivity can be changed freely by fitting values of circuit elements (capacitor) adequately. Since circuit composition of this measurement instrument is very simple, demands for the one of small size and portability are satisfied. Measurement of capacitance and resistance corresponding to the water contents of sand including electrolyte were shown as the applications, and continuous measurement of water status in rice, though it has been regarded as difficult, and the effect of magnetic field on capacitance and resistance of the leaf of plants were shown as the example for detecting plant physiological information.View full abstractDownload PDF (1307K) -
Shogo TANAKA, Tatsuya KATADA1994 Volume 30 Issue 1 Pages 16-23
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSExact measurement of heaving, rolling and pitching of the ship is important in exact searching for seabed patterns by a sonar and also in suppressing the swing of hovercrafts. From these viewpoints, the authors previously developed an on-line automatic ship's attitude measurement system, which used accelerometers appropriately located on the ship. But, having assumed exact knowledge on the rolling axis, the measurement system causes degradation in the measurement accuracy in the case where the rolling axis changes depending on the change of the weight loaded and a wave caused by a big ship sailing nearby.
The paper proposes an on-line ship's attitude measurement system which overcomes the problem. For realizing it, two inclinometers and one accelerometer are effectively utilized, and in the use of the inclinometers the dynamics of the moving elements are taken into account.View full abstractDownload PDF (1598K) -
Yasuhiko MUTOH1994 Volume 30 Issue 1 Pages 24-30
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSAn interactor matrix is a lower left triangular polynomial matrix which is regarded as a generalized concept of the relative degree of a scalar transfer function. In other words, the interactor matrix corresponds to the zeros at infinity of a given transfer matrix. The interactor matrix plays an important role in the calculation of the model matching control parameters for a multivariable minimum phase plant using the polynomial algebraic method.
In this paper, we extend the definition of the interactor matrix so that it corresponds to not only the zeros at infinity but also some prespecified finite zeros of a given transfer matrix. It is shown that, if we replace the interactor matrix by the extended interactor matrix, the polynomial algebraic method can be applied to calculate the model matching control parameters for a multivariable nonminimum phase plant without any further modification.View full abstractDownload PDF (1315K) -
Zenta IWAI, Ikurou MIZUMOTO, Katsumi ADACHI1994 Volume 30 Issue 1 Pages 31-38
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, we deal with the problems of robust stabilizability and model output following control by using output feedback in the presence of additive and/or multiplicative unmodelled dynamics. An allowable range of unmodelled dynamics, which guarantees the uniformly boundedness of all signals in closed-loop by output feedback, is examined for the plant of which dominant part satisfies the almost strictly positive real (ASPR) condition. The design method of model output following control by output feedback is proposed for the plant with ASPR dominant part and unmodelled part which belongs to stabilizable range. The practical design method using precompensator is also considered in case that the dominant part of the plant is not ASPR.View full abstractDownload PDF (1380K) -
Kiyoshi NAGAI, Tsuneo YOSHIKAWA1994 Volume 30 Issue 1 Pages 39-47
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA dynamic manipulation/grasping controller of multifingered robot hands based on the dynamic control and the hybrid position/force control is proposed and discussed in this paper. This controller, using the concept of the manipulating and grasping forces proposed by the authors, consists of a compensator which linearizes the whole grasping system and a servo controller for the linearized system. The distinctive features of the proposed controller are: 1) The grasp parameter, which has the same number of elements as that of the essential dimension of the internal force, is used for the controlled variables of the grasping control. 2) It decomposes a total force required to apply the grasped object into the manipulating force for each finger. First, the kinematical constraint among the fingers and the dynamic equations of the fingers and the object are presented as basic equations. Second, the dynamic manipulation/grasping controller is proposed. Finally, simulation results are given to show the validity of the proposed controller.View full abstractDownload PDF (1537K) -
Fumitoshi MATSUNO, Satoshi SHIBATA, Yoshiyuki SAKAWA1994 Volume 30 Issue 1 Pages 48-53
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a simple model with considering flexibility of constrained manipulators is proposed by introducing a set of equivalent springs. On the basis of the proposed model we derive a controller, which compensates the vibrations of the contact force. For measuring the vibrations and the contact force, accelerometers and a force sensor are used. Output signals of the sensors are fedback to driving motors for controlling the position of the end-effector and the contact force. Experimental results are shown.View full abstractDownload PDF (1304K) -
Yoshiki MATSUO, Takeshi INABA, Takashi HIROMATSU1994 Volume 30 Issue 1 Pages 54-63
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, a controlled system for an active-cab-suspension constructed with hydropneumatic actuators is considered, which is intended to improve ride comfort of a truck.
At first, a controller is designed using YJB parametrization of all stabilizing compensators and experiments is carried out to verify its feasibility. The parameter is determined by graphical technique in frequency domain so that the controlled system has sufficient ride comfort. Experimental results show that the considered active-cab-suspension can greatly improve ride comfort. But they also show the necessity of consideration for other factors of the controlled system such as transfer functions from measurement noises to the stroke length and to the control input.
Then practical design of the controller is proposed. This is based on H∞ control theory, that can achieve systematic loop shaping of multi-input/multi-output systems. The controlled system is augmented with frequency weightings to state its design as standard output feedback H∞ control problem. Relations between these weightings and some significant transfer functions of the system are mentioned. Decision of weightings is proceeded so that they shapes these transfer functions desirably. Simulations and experiments using measured actual vehicle acceleration data confirm that the resulting system has remarkable improvement of ride comfort with the limited stroke length, and high robustness against measurement noises. This shows validity of application of H∞ control theory to designing a controller of the active-cab-suspension.View full abstractDownload PDF (2766K) -
Noboru NOGUCHI, Hideo TERAO1994 Volume 30 Issue 1 Pages 64-71
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper, in order to contrive a method that changes a vehicle for farm and construction use into an autonomous vehicle, an attempt was made to create an optimal route in field by using genetic algorithm (GA). First, kinematics of the vehicle was described in a simulator that was a nonlinear dynamic model with neural networks (NN), and its accuracy was investigated using trained data and untrained data. Next, the method of creating an optimal route was contrived by using the NN simulator and GA. It was demonstrated that this method was effective to get an optimal route and the time series of steer angles. The optimal route was created under some boundary conditions and constraints. It was also possible to determine an obstacle avoiding route through this method.View full abstractDownload PDF (1875K) -
Qingxing LIN, Kiyohiko NAKAMURA, Atsunobu ICHIKAWA1994 Volume 30 Issue 1 Pages 72-78
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe purpose of this paper is to investigate liveness of a special class of colored Petri net (CPN) with the structural color matching and the firing color matching introduced by Q. Lin and A. Ichikawa. A CPN is said to be a colored marked graph (CMG) if it is structurally marked graph when color difference in arcs and tokens is ignored. Petri net equivalent to colored marked graph (ECMG) is a new class of a net which has a special structure different from marked graph, conflict free Petri net and free choice Petri net. The sufficient condition is given for existence of a live marking in ECMG by means of deadlock, trap and fairness.View full abstractDownload PDF (1646K) -
Xiaohua HU, Akihiro KANESHIGE, Katsuaki ONOGI, Yoshiyuki NISHIMURA1994 Volume 30 Issue 1 Pages 79-87
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn the stepwise refinement of discrete event systems, the formal specification step plays an important role because it makes the mathematical verification of each refinement step possible. In this paper, we firstly propose a method for the specification of discrete event systems based on the simple idea that discrete event systems can be modelled as many-sorted algebras (a number of sets together with a number of functions on those sets) as well as abstract data types in software engineering except that the state-transition functions included in such systems may be partial functions. The proposed method extends the method of algebraic specification of abstract data types so that it can also be used to specify the partial state-transition functions. Then, we study the problem how to verify one system refines another based on the following ideas: Let A, A' be two specifications of discrete event systems, and M(A), M(A') be those systems deduced from A, A' respectively. If we can obtain a syntactically verifiable condition (C) for A, A' which guarantees M(A') be a refinement of M(A), then, we can verify that M(A') refines M(A) by simply verify that the condition (C) is satisfied by A, A' syntactically.
We also present such a condition (C) and point out that it is syntactically verifiable for specifications of which equations can be treated as rewrite rules satisfying finite and unique termination.View full abstractDownload PDF (1650K) -
Yoshinobu HABUKA, Eitaro AIYOSHI, Naoki NEGISHI1994 Volume 30 Issue 1 Pages 88-96
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn order to realize the desired input-output relations of a neural network, the Back-Propagation has been successfully used as a learning algorithm to adjust the synaptic weights of a multilayer network. Not only reproduction ability of the learned input-output relations, but also additional abilities, such as a generalization ability for inputs which the network has not yet learned (non-training data), are required of the organized network. But these abilities are generally competitive, and then balancing between them is one of the unsettled matters in the neural network learning.
In this paper, we formulate the learning problem considering generalization as a inequally constrained optimization problem which requires minimization of the magnitude of synaptic weights to obtain the generalization ability for non-training data, under the satisfactory conditions that the output errors in response to the training data are less than the given permissible levels. By assignment of parameters of the permissible levels, the balancing of the mentioned two abilities is achieved. Then, we can define the learning algorithm as an iteratively searching process for the optimal solution to the formulated problem by starting from the non-feasible initial state of the synaptic weights, which is an unsatisfactory state for the output errors. As the learning algorithm, we adopt the augmented Lagrangian function method, which is known as an effective constrained optimization method. The proposed method is tested on simple pattern recognition problems in order to certify the generalization ability in the organized neural network by our learning algorithm.View full abstractDownload PDF (1915K) -
Satoshi ITO, Hideo YUASA, Masami ITO1994 Volume 30 Issue 1 Pages 97-103
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe purpose of this paper is to introduce the idea of an autonomous decentralized system to a pictorial pattern recognition based on an autoassociative memory and to examine its possibility.
Synergetic computing proposed by H. Haken is one useful method of the construction of the autoassociative memory. Since prototype pictures are treated as the vector data in this method, the two-dimensional informations would have been lost. So, we may be able to reform this system.
One of the examples that the patterns are formatted by the two-dimensional interaction is found in the chemical reactions like a B-Z reaction. The mathematical models of these have been studied by use of the reaction-diffusion equation.
In this paper we apply the differential equation (the reaction-diffusion equation) which describes the pattern formation from the viewpoint of “autonomous decentralization” concept to make an autoassociative memory. Here we compose the system so that it recalls the memories by self-organization of the best inner structure, by which we propose one of the examples that show the composition of the autonomous decentralized system.View full abstractDownload PDF (2133K) -
Zhong-Qi QIU, Shiro USUI1994 Volume 30 Issue 1 Pages 104-111
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a new algorithm for automatic transcription of drums by the adaptive processing method. In transcribing performed drum music, a system must extract each beat and must recognize the drum's type at each beat.
In order to extract a drum's beating time based on time-domain, we employed recursive estimation technique which should make transient change extraction more accurately and eliminate the necessity of frequency analysis. The approach presented here utilized the normalized LSL algorithm with the likelihood variable estimation, including the threshold processing and local method. This recursive algorithm updates its representation at every music signal sample using exponentially weighted past data. Thus it is possible to track the beating changes in the drum music signal. From the extracted beating times, we modeled the drum music nonstationary signal by an AR model with the time-varying coefficients and estimated the time-varying coefficients using the RLS adaptive algorithm to obtain a time-frequency spectrum of the drum signal. With the obtained time-frequency spectrum, the drum's type recognition can be carried out by the pattern matching method. Finally, we combined the beating time extraction and the drum's type recognition to form an automatic transcribing system of the drum music, and presented experiment results of transcription to illustrate a validity of the proposed system for the drum machine data and the real drum music data.View full abstractDownload PDF (1569K) -
Ilhwan KIM, Hideki OHTSUKA, Hikaru INOOKA1994 Volume 30 Issue 1 Pages 112-114
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe propose a dynamic model for human fingertips where the maximum allowed displacements of Maxwell and Kelvin models are limited. Experimental results show the proposed model is fit to the force-displacement data obtained by probing the fingertip.View full abstractDownload PDF (322K) -
Kai NAKANISHI, Akira KOJIMA, Shintaro ISHIJIMA1994 Volume 30 Issue 1 Pages 115-117
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSFor a system with delays in control, we investigate the relation between the value of time delay and robust stabilizability. It is clarified that the achievable margin of robust stabilizability against additive perturbations exponentially decreases to zero as the value of time delay increases.View full abstractDownload PDF (361K) -
Tadashi EGAMI, Takeo NISHIYAMA1994 Volume 30 Issue 1 Pages 118-120
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSOptimal preview repetitive control system is applied to air slide linear DC motor in this paper. It is confirmed that periodic disturbance is suppressed and position of moving magnet tracks the trapezoidal desired signal without undershoot in experimental studies.View full abstractDownload PDF (355K) -
Shinsuke TAKAHASHI, Teruji SEKOZAWA, Makoto SHIOYA1994 Volume 30 Issue 1 Pages 121-123
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSNew scheme for calculating the asynchronous fuel injection quantity is proposed in car engine control. In this scheme, the optimum asynchronous fuel injection quantity is determined on the basis of intake air prediction and fuel condition estimation.View full abstractDownload PDF (413K) -
Control of Elevator by Digital Acceleration Control Method and Approximation of Angular AccelerationEiji TADOKORO, Shouyu WANG, Takeshi TSUCHIYA1994 Volume 30 Issue 1 Pages 124-126
Published: January 31, 1994
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a digital acceleration control method on elevator model and an approximation method of angular acceleration with angle and angular velocity.View full abstractDownload PDF (317K)
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