All issues
Volume 26, Issue 9
Displaying 1-22 of 22 articles from this issue
- |<
- <
- 1
- >
- >|
-
Takeshi HATSUZAWA, Kouji TOYODA, Yoshihisa TANIMURA1990 Volume 26 Issue 9 Pages 983-988
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA metrological electron microscope system to measure critical dimensions of microfeatures in VLSI production has developed. The system has two laser interferometers as absolute scales, whereas the electeron beam is used to detect the microfeatures. The resolution of the interferometer for the main scanning direction X is 0.8nm (λ/800), and system repeatability is 9nm. By using this system, standards for the calibration of scanning electron microscopes can be established in sub-micrometer range.View full abstractDownload PDF (3126K) -
Masaaki ADACHI, Youichi KITAGAWA, Tetsuya MATSUMOTO, Nozomu TAKEUCHI1990 Volume 26 Issue 9 Pages 989-994
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA new continuous profile measurement using a serial multi-point method is proposed. In a conventional serial multi-point method, a few distance-sensors which have the same lateral sensitive areas are positioned on a sensor head. In this new profiling method one distance-sensor having extremely narrow sensitive area is positioned at the center of the sensor head, before and behind of which two distance-sensors having wide sensitive areas are positioned. An output from the narrow sensor represents the distance from the sensor head to the point being measured. While an averaged value of the outputs from the two wide sensors represents the distance from the sensor head to the surrounding area about the point. Thereby, the difference obtained by subtracting the latter from the former provides the height value of the point from the level of the surrounding area. The difference varies with a local profile being measured. When the sensor head is scanned on a surface with a constant velocity, change of the difference signal has high sensitivity about short-wavelength components in the surface profile and has low sensitivity about long-wavelength components. This characteristic sensitivity against spatial frequencies can be theoretically calculated from the sensor head configuration. Then, all the wavelength components in the change of the difference signal are corrected with the characteristic sensitivity to have unity sensitivity using a computer filtering. In the experiment, the usefulness of the method has been confirmed through the computer simulations as well as through the measurement of a step hight standard using an optical interference microscope.View full abstractDownload PDF (750K) -
Yasunori SASAKI1990 Volume 26 Issue 9 Pages 995-1002
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper proposes practical microwave, radiative transfer model of atmosphere with rain over wide range of rainfall rate from 0 to 50mm/hr, based on observational results. Typical atmospheric substances which interact with microwave are oxygen, water vapor, cloud water, and rain drop in this model. The typical distribution in the atmosphere was assumed for the first three substances, and rainfall rate was measured from ground-based and satellite measurements together with brightness temperature of atmosphere. The radiative transfer equation was solved in order to estimate absorption and scattering coefficients of rainfall, employing above data, and the microwave radiative transfer model, which takes account of multiple scattering effect of raindrop, was derived.
This model was, in turn, applied to error estimation in microwave radiometeric observation of ocean. Sea surface temperature and sea surface wind were objective oceanic environmental parameters. It was noticed from the simulation that the atmospheric effect was of the most significance in observation of above parameters and we can conclude that the microwave observation would be useful in the case that the rainfall rate is at most up to 2mm/hr.View full abstractDownload PDF (1567K) -
Yoshito OHTA, Shinzo KODAMA1990 Volume 26 Issue 9 Pages 1003-1008
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper considers the problem of reducing sensitivity over a frequency band for possibly infinite dimensional MIMO systems. The following two complementary results are proven. If the plant has nonconstant inner part, then the sensitivity over the band cannot be made arbitrarily small when the overall sensitivity is kept bounded. On the other hand, if the plant is outer and satisfies some collateral conditions about zexos on the imaginary axis, then the sensitivity over the band can be made, arbitrarily small while the overall sensitivity is kept bounded. These are extensions of results for non-minimum phase/minimum-phase rational plants.View full abstractDownload PDF (777K) -
Yuh YAMASHITA, Masasuke SHIMA1990 Volume 26 Issue 9 Pages 1009-1014
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSFor linear analytic systems, input-output linearization problem was already solved by Isidori, et al2) in terms of the nonlinear structure algorithm3). In this paper, we study the input-output linearization problem for general nonlinear system x=f(x, u), y=h(x).
Firstly, we give a simple necessary and sufficient condition under which the input-output behavior is linear. The condition is trivial if the system is linear analytic system2). Secondly, the nonlinear structure algorithm is extended for general nonlinear systems. The extended algorithm yields necessary and sufficient conditions to be satisfied by plant for the input-output linearization via state feedback, whose proof provides a state feedback law.View full abstractDownload PDF (619K) -
Kiyotaka SHIMIZU, Satoshi ITO1990 Volume 26 Issue 9 Pages 1015-1022
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSQuasi-Newton methods are extended to optimization problems with an operator constraint in Hilbert spaces. In these algorithms, quadratic programming subproblems with a set constraint are iteratively solved to obtain estimates of Lagrange multipliers, and a sequence of search directions is generated with these estimates.
Then these methods are applied to optimal control problems with state inequality constraints. In this case, the control problem is reduced to a series of nonnegatively constrained quadratic programming problems in a function space and they can be easily solved, e.g., by clipping-off techniques. A numerical example is also presented to illustrate the usefulness of the proposed algorithm.View full abstractDownload PDF (1018K) -
Hideki KOKAME, Hiroshi KIDA, Takehiro MORI1990 Volume 26 Issue 9 Pages 1023-1028
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn the case where stability of a linear system with uncertain parameters is concerned, realizable system matrices are often described as a polytope of matrices. However, stability condition of a matrix polytope has not been fully developed and moreover easy-to-compute stability criteria are few. Among them is such that if a positive-definite quadratic form be a common Lyapunov function for all vertex members of the polytope, then the matrix polytope is stable.
In this paper, this criterion is extended to the case where a number of positive-definite quadratic forms are available, leading to a new easy-to-compute criterion which can assure stability for a wider class of problems. This stability criterion can be performed on a standard routine for linear programming. The class of multi-tuples of quadratic forms that satisfy the stability criterion is characterized in relation to other classes of the similar meaning. A systematic use of the proposed criterion for stability of perturbed systems is demonstrated by an example.View full abstractDownload PDF (825K) -
Identification Experiments for Robot ArmShuichi ADACHI, Junji OAKI, Takashi SHIGEMASA1990 Volume 26 Issue 9 Pages 1029-1035
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe least-squares (LS) method is one of the most familiar and useful system identification method. However, there are many problems to be solved when one applies the LS method to the actual system. For example, it is difficult to identify lower frequency region accurately, because the cost function in the conventional LS method weights higher frequency region. This paper proposes a new identification method which uses multiple decimation operation, so we call it MD (Multi-Decimation) method. The decimation, consists of the low-pass filtering and the resampling whose sampling rate is decreased, is widely used in the area of the signal processing. The advantages of the MD method are (a) By deviding the frequency region of the system, the characteristics in lower frequency region can be identified accurately as well as that in higher frequency region, (b) Data scaling can be carried out individually in each devided frequency region, and (c) By focusing on the narrow band, vibrational characteristics which are difficult to identify by the LS method can be identified accurately.
In industrial robots, there are many vibrational modes which are caused by speed-reduction mechanisms, in the wide frequency range. It is necessary to identify these vibrational modes accurately so as to design stable servo controllers. So, we apply the MD method to the identification of robot arm, and we show the efficiency of the MD method through the identification experiments.View full abstractDownload PDF (889K) -
Sakae KIMURA, Ichiro MITSUYOSI, Makoto KIMURA1990 Volume 26 Issue 9 Pages 1036-1042
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA pneumatic servo presented has a feature to set a by-pass valve in a conduit with a proper resistance connecting both rooms in the power cylinder, and to make the valve open and closed at each proper time for the improvement of damping in positioning of the step response. In application of this method to a single rod cylinder, a distinct difference is found between cases of extension and retraction of the piston. In the latter case, the merits of the by-pass method are reduced a little, so another little modefied method also has been examined. Means of making use of the by-pass valve properly including the case of double rod cylinder are presented to each case. Experimental results are compared with computer simulations, and good coincidence is obtained.View full abstractDownload PDF (759K) -
Shoji TAKAGI, Wei WU, Naohiko KOAKUTSU, Hideo KAWABATA1990 Volume 26 Issue 9 Pages 1043-1050
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper is concerned with a new discrete time adaptive control scheme for robotic manipulators. In order to reduce the number of unknown parameters, a nonminimum phase discrete time model of manipulators is used for the plant model. Because the usual model reference adaptive control scheme can not be applied to nonminimum phase plants, we construct a quasi-model-reference adaptive control system which permits small error between the reference model and the plant outputs. The asymptotical stability of the control system in the large is proved under a certain condition. A method of determining the parameters of the control system is proposed. The validity of the proposed control system is confirmed experimentally.View full abstractDownload PDF (1081K) -
Akira TOZUNE1990 Volume 26 Issue 9 Pages 1051-1057
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSSynchronous inductor motors identical in construction to PM-type stepping motors are widely used in chart paper drive and other applications owing to their characteristics of constant speed in a low speed range and excellent start/stop performance. This type of motor is usually driven from single phase source with a phase-shift capacitor.
This paper discusses some methods for choosing phase-shift capacitor. The influence of capacitor value on motor characteristics is being investigated showing that there exists specific values of capacitor for making pull-out torque maximum and alternating torque minimum.
Based on these results, three criteria to determine the value of capacitor are presented.These are;
1) Minimum alterating torque.
2) Maximum pull-out torque.
3) π/2 phase difference between main and auxiliary phase currents at standstill.
A comparison is achieved between pull-out torque, alternating torque, and starting characteristics under the above three conditions.
As a result, “minimum alternating torque condition” is recommended for proper choice of capacitor value for the normal use of inductor motors.View full abstractDownload PDF (743K) -
Sadayuki TSUGAWA, Satoshi MURATA, Takeshi HIROSE, Teruo YATABE1990 Volume 26 Issue 9 Pages 1058-1065
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA vehicle following system by autonomous vehicles with vehicle-to-vehicle communication, named a soft-linked vehicle system, is described. Each vehicle in the system has functions of autonomous navigation based on dead reckoning, and the vehicle-to-vehicle communication for soft-linking. The dead reckoning system uses both wheel speeds of each vehicle measured by rotary encoders. The vehicles are driven linked on a string with constant and small gaps by the vehicle-to-vehicle communication without couplers of hardware, or run independently from each other. The purpose of the system is flexibility and efficiency. Velocity control of vehicles under soft-linking is formulated to a pole assignment problem to maintain the gaps and to avoid collisions between vehicles. Steering control of a vehicle is determined by a target point following algorithm. Steering on a vehicle at the head of a string is controlled so as to hit a series of target points successively which are put along a route. On each of following vehicles steering control is found based on data of its preceding vehicle by the algorithm. Data necessary to the soft-linking are a control input, velocity, position and orientation of the preceding vehicle, which are transmitted through the vehicle-to-vehicle communication. A medium for the communication is infrared, and the data transmission rate is 9600 bps., A vehicle used in this study is a battery-powered automated, guided vehicle of 1.3m×0.75m. Experimental results of the soft-linked vehicle system by two vehicles on driving along a straight line and a lane changing maneuver at the velocity of 0.4m/s show that the velocity and steering control proposed in this paper is effective to the soft-linking.View full abstractDownload PDF (1551K) -
Akihito SANO, Junji FURUSHO, Yasushi IKAMI1990 Volume 26 Issue 9 Pages 1066-1073
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSA force distribution in locomotion systems containing closed kinematic chains is a difficult problem since a degree of freedom of the systems is reduced by certain holonomic constraints. Control of the force distribution in biped locomotion robot during double-support phase is discussed in this paper.
Inequality constraints on reaction forces are considered, in addition to equality constraints which specify desired trajectories of some joints of the biped locomotion system. Minimizing consumption of joint torques under these constraints is used to obtain a proper distribution of input torques. We put an angular momentum of the locomotion system close to reference function given in advance by using this torque distribution method which prevents the foots from any slipping and the soles from any lifting. The effectiveness of the proposed control method was examined by experiments with our BLR-G2 walking robot.View full abstractDownload PDF (1547K) -
Hiroshi MAEDA, Shuta MURAKAMI1990 Volume 26 Issue 9 Pages 1074-1080
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper is concerned with a natural language interface in an interactive fuzzy decision-making support system (FDSS). A natural language interface in an interactive system is very desirable because the users of the system are not required much preliminary knowledge.
FDSS partly uses a natural language interface of japanese language in the case where users input their evaluated objectives for a multi-objective decision problem. When the user inputs an evaluated objective by natural language expression, FDSS can extract a keyword representing its concept from the expression. The natural language interface is designed by the following concepts: 1) the dictionary for japanese language processing is as little a scale as possible, 2) the processing for appearance of unregistered words in the dictionary is developed in the basis of fuzzy theory. The reason of this is that since the natural language interface is only one part of FDSS, the processing for it cannot be a largescale in consideration of operationality and responsibility on FDSS. Consequently unregisterd words frequently appear.
An algorithm for treating the unregistered words is presented by partial character matching, similarity relation among registration words, and approximate reasoning. The algorithm was evaluated with regard to 158 real examples, which 70 subjects inputted to FDSS by free natural language; it was verified that the algorithm was very useful.View full abstractDownload PDF (948K) -
Seiichi KAWATA, Atsushi WATANABE, Yasumaru KUBO1990 Volume 26 Issue 9 Pages 1081-1088
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSIn this paper an automatized system of designing for control systems is developed. The developed system consists of three layers: tool layer, design procedure layer and meta-rule layer. The tool layer executes basic calcu ation, simulation and graphics management. The design procedure layer executes control system design algorithms such as designing phase lead/lag compensation. The meta-rule layer forms an expert system in which the truth maintenance system automatizes the control system designing process. The whole system is developed mostly by Prolog except that the Prolog predicates in the tool layer are constructed by C language which exists only as the infrastructure of this system.View full abstractDownload PDF (2636K) -
Shigeru HINATA, Masayuki SAKURAI1990 Volume 26 Issue 9 Pages 1089-1091
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe measurement technique of local liquid velocity using two probes of the optical fiber refractometer, which can detect the signal of saline solution as a tracer is described. The relative error on the local velocity is within ±8%.View full abstractDownload PDF (282K) -
Hideto IDE, Shizuaki TAKAHASHI, Masaru YARITA1990 Volume 26 Issue 9 Pages 1092-1094
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSEvoked brain potential called “P300” was discovered while monitoring brain activities of patient counting the number of sound stimulation. However, there are some problems; it is difficult to EEG the region beyond bones. We propose a new method for EEG and local regions of the brain.View full abstractDownload PDF (1476K) -
Akira KANEKO, Seiichi SHIN, Kazuaki ANDO1990 Volume 26 Issue 9 Pages 1095-1097
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThis paper presents a new adaptive law which is robust to bounded disturbances. It is a modification of the ε-modified adaptive law. The error convergent domain of the proposing adaptive law is smaller than that of ε-modification.View full abstractDownload PDF (338K) -
Yuichi CHIDA, Shinji HARA, Tsutomu MITA1990 Volume 26 Issue 9 Pages 1098-1100
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSThe absolute minimum value of the complementary sensitivity function of discrete-time state feedback systems is shown to be the product of the unstable poles of an open loop system.View full abstractDownload PDF (403K) -
Hak-Kyung SUNG, Shinji HARA1990 Volume 26 Issue 9 Pages 1101-1103
Published: September 30, 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSWe derive an integral-type constraint on the complementary sensitivity function in digital control systems. Some design guidances are proposed for the pole assignment of digital controller with computational time delay to improve the complementary sensitivity characteristics.View full abstractDownload PDF (352K) -
1990 Volume 26 Issue 9 Pages 1104a
Published: 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (102K) -
1990 Volume 26 Issue 9 Pages 1104b
Published: 1990
Released on J-STAGE: March 27, 2009
JOURNAL FREE ACCESSDownload PDF (102K)
- |<
- <
- 1
- >
- >|