The source current detection type AF has a merit of robustness to the load variation, but a problem of the resonance between the AF and an LC filter often arises, if an LC filter is connected parallel to the AF. In this paper, Double-LISN circuit based AF, resonance analysis and the simulation results comparing with experimental ones are studied and discussed.

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Speed feedback into driving force is an effective measure to add damping for motion control systems with no damping element, while effect of the feedback is decreased for systems with larger delay. A passenger car powertrain system is prone to be oscillatory and engine torque has structural dead time. An engine torque control algorithm that generates engine torque command from an accelerator operation to reduce vehicle longitudinal vibration without deteriorating acceleration using an online vibration model is developed. Numerical simulations and experiments show effectiveness of the proposed method.

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This report first explains a prototyped constant current control circuit, which has successfully realized constant amplitude of the stator tip while maintaining a state of resonance, and that leads to the experimental results of velocity reduction proportional to the load torque under the constant current drive. Secondly, a new friction model based on these findings is proposed.

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In this study, we built a real-time control system for the ultrasonic motor by RT-Linux to develop the artificial muscle which combined ER fluid and ultrasonic motors. We measured on the frequency responses for the physical model construction of the ultrasonic motor with several load. Then, we discuss the optimal controller for the ultrasonic motor.

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Magnetorheological (MR) fluids are materials that change their rheological behavior by an applied magnetic field. We have developed MR-fluid actuator. In this paper, we investigate the dynamic characteristics of the MR-fluid actuator and aim to improve the response. The transient magnetic analysis is examined in consideration of the eddy current. Finally, we realize a much faster MR-fluid actuator.

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Feasibility study of PCR using electrostatic manipulation of micro droplets is discussed. Adherence of droplets to the surface has been a difficult hindrance to overcome when controlling PCR solution in liquid medium. Different types of medium immiscible with the droplets are tested and n-octane enables electrostatic manipulation of PCR droplets. The concept of a novel micro PCR device is proposed.

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This paper presents a new method for preparing micro droplets inside the liquid layer at a T-junction in a microchannel network. The relations between droplet size, flow speed, and channel size are studied. The droplet size is easily varied by changing the flow conditions in the microchannels. The size distribution of the resulting droplets is very narrow.

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We developed the biologial cell rotation system using electrostatic force, which is excellent for manipulating a minute object. This system is the important element of the automated nuclear transplantation system. This system could rotate mouse’s oocyte three dimentionally. And, it was confirmed that the rotation by electrostatic force did not influence fertilization and development ability of oocyte.

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We have developed a new method to measure the hydraulic conductivity of cell membrane (L_p), based on the principle that two liquids flow in laminar flow though relatively narrow space. The developed method has advantages that a number of required cell sample is only one, and accurate measurement can be made as compare with the conventional method.

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Chromosomal DNA consists of exons and introns. Exsons carry useful information and introns are “junk” DNA. However, introns may serve as a protection for unwanted destruction of those blocks of useful exons in case of mutation which happens often in the process of evolution. This nature of introns was introduced into genetic algorithms to improve the robustness of GA search.

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Recently, genetic algorithms and other newly developed search techniques have received a lot of attention, because of their easy to use nature in many engineering problems. They are capable of locating a good approximate in extremely large search spaces with a reasonable amount of computational effort. Leaf Cellular Automata (LCA) developed and evaluated in this study are also one of search algorithms inspired by photosynthetic procedures a leaf. Cellular automata are used as fundamental technique.

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Digital redesign is carried out to discretize an analog PWM control system used for a stepping motor. A new substitution model is used for analog transfer functions and a ramp-type approximation for the PWM generation. The redesigned controller is implemented on a DSP and shown to have the performance which is almost identical to that of the original analog controller.

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In this paper we describe a simple elevator modeling method that deals with supervisory control logics such as dynamic zoning. It can be applied to design equipment and tune supervisory control logics. We developed this method by extending the techniques used for calculating round trip times. We have conducted a simulation to confirm the effectiveness of this model

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In this paper, we propose a framework for obtaining the optimal solution of an elevator operation problem by applying Branch-and-Bound method, where it is assumed that all information about the passengers are given. The problem is solved by determining the assignments of passengers to elevators and the processing order of passengers for each elevator. The validity of an existing rule to decide a car service is examined by comparing the results with the optimal one.

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An energy conservation optimal control system using information network is presented in the paper. The special feature of the control system is to control total equipments in a factory for energy conservation at low cost using information networks. The control strategy consists of 2 parts. (1) Data mining algorithm to examine energy consumption for a factory. (2) Optimal control algorithm to control many manipulating values at the same time. The algorithm adopts model predictive control method. The system performance is tested through energy consumption simulations for the factory. whose model is proved by the comparison with measured data for 1 month. Finally the system was proved to decrease energy consumpion by more than 8% that is final goal.

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The necessity of succeeding the knowledge of expert operators familiar with all production area is becoming important. This paper discusses the Knowledge Management of expert operators at plant floors, where manual interventions are still key productivity bottlenecks. Meta-operation concept is an improvement cycle by converting tacit operators’ knowledge into knowledge base, and deputizes their work as an ultimate solution.

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The warehousing system consists of several storage space, pallets and overhead crane conveying the products. Due to the complexity of the movements of the products in warehousing system, it is difficult to obtain a reasonable schedule for product allocation. In this paper, we propose a determination method for product allocation schedule in automated warehousing system by using the simulation-based optimization method. The simulation module is composed of product receiving and product picking simulator. Several heuristic rules are investigated by using the developed simulator. It was confirmed that the location of received procucts highly influences the handling cost for picking the products and total distance traveled by the overhead crane. In order to optimize the storage location of products, the potimization system using simulated annealing method is also developed. The performances of a large scale problem derived by the proposed system are considerably improved compared with those derived by heuristic algorithm.

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A study on the characterization of a controlled-clearance piston gauge was performed. In this study, the Heydemann-Welch model was used to define the controlled-clearance piston gauge as a primary pressure gauge. The parameters needed for the model were determined from the measurements, and the characteristics of the controlled-clearance gauge were evaluated along with their uncertainty.

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A new method to improve the accuracy of measured axle weight of an in-motion vehicle is proposed and the method is evaluated by applying it to the simulated data composed of a known axle weigh and, as dynamic components, measured accelerations of an actual vehicle body. As the result, the efficiency of the method is confirmed.

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The necessity of quick and accurate mass measurement is becoming large necessary depending on the development of automations in industries, especially in processing lines. In the previous paper, author has proposed a new method that can interpolate frequencies using the complex least mean square (LMS) algorithm. Author applied this method to obtain the mass of objects under the dynamic conditions using resonance frequencies and damping ratios. Finally, the effectiveness of this proposed method was examined by experiments.

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A novel weighing method for in-motion vehicles is set up in this paper. The measurement principle is described and the estimation for measurement uncertainty by Grey Error Theory is presented. Theoretical analysis and experimenta1 research are given to show the method could be used to solve the weighing problem for in-motion vehicles with higher accuracy.

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A method for evaluating forces acting on the moving part of pneumatic linear bearings has been proposed by the author and is under development. The total force acting on the moving part is accurately measured as the inertial force using an optical interferometer. Then the components of the force, such as the force component depending on position, the force component depending on velocity, are evaluated using the least squares method. The present status of the development and the future prospects will be discussed.

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The micro cantilever made of entirely plastic material has been developed. The probing tip, cantilever and base are made of same photo plastic. By arranging the geometry of the cantilever, its spring constant and resonant frequency is controlled. The low Q of the polyimide improves the stability of the force controlled atomic force microscope. The fabrication error in cantilever geometry was 1.5%. The estimated resonant frequency has a good agreement with the designed value.

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Some studies on inhomogeneity of type K thermocouples were reported, but inhomogeneity of each thermoelement of the thermocouples was not reported. We studied inhomogeneity of each thermoelement of T thermocouples and verified experimentally that inhomogeneity of each thermoelement can be measured by using grounded-junction sheathed thermocouples. After annealing at 400 degrees Celsius and 250 hours, the positive leg (Copper) of T thermocouples did not reveal no inhomogeneity but the negative leg(Constantan) revealed some inhomogeneity.

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The freezing point of silver is realized using an open type cell. The uncertainty of the thermocouple calibration at this temperature was evaluated using Pt/Pd thermocouples. The sources of uncertainty estimated were stability and repeatability of the plateau, temperature distribution in the cell, impurity effect of the metal, surroundings pressure correction and hydrostatic pressure correction. The combined standard uncertainty is 7, 8mK.

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For uncertainty assessment on the calibration of Pt/Pd thermocouples at the freezing point of copper, uncertainty components of the automatic ice point for the reference junction, the digital voltmeter, the thermocouple extension wires, and the copper wires were estimated. By combining these components and the others obtained elsewhere, the expanded uncertainty (k=2) was estimated to be approximately 0.11°C.

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NiC eutectic point (approximately 1329°C) is studied as a fixed point for the calibration of Pt/Pd thermocouples that have useful measurering temperature up to 1500°C. It is found that reproducibility in the temperature of Melting Plateau is 0.1°C and that that of Freezing Plateau is 0.1°C.

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It is well known that standard platinum resistance thermometers (SPRTs) are delicate against mechanical shock and vibration. This delicacy causes resistance instability that is one of the most effective factors of uncertainty in precise measurement, such as the fixed point comparison. Development of a mechanically-stable SPRT reduces this uncertainty. As a preliminary experiment, we evaluated mechanical characteristic of existing types of SPRT.

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The freezing point of tin, one of the temperature fixed-points defined in the ITS-90, is newly developed and evaluated. The temperature stability of the furnace is within ±1.5mK for 24 hours and temperature distribution is within 2mK over 20cm. To realize a stable plateau after a large amount of supercooling, the air blow cooling method is introduced instead of the conventional method. The temperature during the plateaus decreases only 0.3mK for 8 hours and a good repeatability within ±0.026mK is obtained in ten measurements.

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The head-neck complex(HNC) is modeled and identified when the trunk of seated human body is exposed to the horizontal (fore-and-aft) vibration. According to the results of the frequency response function of the system, a double-inverted pendulum is considered as a model for the HNC. The frequency domain identification method is used to identify the HNC. The viscoelastic parameters of the neck are also obtained. Good agreement is obtained between the experimental data and simulation.

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There is scarce information on Ariake Bay though it is very controversial from a point of view of ecology. The marine harvests in the bay have been highly damaged. The decrease of the productivity of the bay is quite apparent, so we will have to clarify the main negative factors. In the present study, we attempt to disclose the special features of this inner bay by a time frequency approach and a nonlinear method along with the satellite observations for better understandings on the bay and obtaining a clue to prevent more damages. These approaches aim to obtain some findings on this bay, especially a delicate rhythm of tidal movements which may have to do with high productivity of the bay.

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We analyze hourly-based tidal data acquired at the Izu Islands and the Kii Peninsula to investigate the behaviors of the Kuroshio’s flow axis because it has a remarkable effect on the tidal fluctuation when its flow axis approaches the southern coasts of Honshu Island. The time-frequency analysis by a wavelet transform and the nonlinear time series analysis are employed to demonstrate the effects of Kuroshio on the tide. The present study aims to reveal the tidal behaviors under the influences of Kuroshio through the visual illustrations of the results by the wavelet transform. In addition, the phase trajectories of the time series also disclose a plausible direction of the Kuroshio’s flow axis.

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[in Japanese]

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This paper proposes an unconstrained measurement system of person’s heartbeat under walking. This system uses a cloth like a vest which has a built-in phonocardiographic (PCG) sensor. With the system, the PCG sensor extracts the person’s heartbeat signal through a vibration of the sensitive element of the sensor and then the periods of heartbeat and walking are simultaneously measured by a pattern matching between the filtered output of the sensor and a linear combination of the sinusoidal functions reflecting the two periods of the heartbeat and walking.

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The purpose of this paper is to find characteristics of body and physiological response to ship rolling created by the ship’s bridge simulator and difference to horizontal visual angles of image simulation. We measured subjects’ body sway snd R-R interval for three experienced persons and three inexperienced persons at four horizontal visual angles. Also, rolling angle controlled by changing wave height from zero to eight meters at one meters interval.

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This paper describes a directional gamma-ray detector with different types of scintillators. The detector, which positively increases directional sensitivity to incident gamma rays, has been developed to measure energy and a direction of gamma rays, and to search radiation sources such as radioisotopes. Experimental results have shown that this detector has a potential foe practical use in real fields.

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The method was proposed for examining the characteristics of materials from impact sound. This mnethod was designed to estimate the elasticity of materials, non-destructively and easily. It becomes difficult to estimate accurate elastic moduli of the vibration as the temperature rises, because of the noise and damping. In this study, we introduce the time-frequency analysis for estimating to estimate the accurate elastic moduli. We examine the effectiveness of the short-time Fourier transform and the wavelet transform.

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Images of a simple cubic model with its size bigger than a pulverized particle were acquired from two different directions using a microscopic camera. Each coordinate of the characteristic points on the model was precisely obtained to verify its 3-D shape by our image processing technique. Application of the technique to the pulverized particle confirmed the possibility to define its 3-D shape.

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The processes of food industry have remarkably progressed in the quality control and various analyzers are employed in the progresses processes. This paper describes how to identify the liquid flowing in the pipeline by multi-sensor fusion method. Here, we present a method that employs three different sensors to identify and discriminate the various liquid and different densities.

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We measured transient of the driver’s viewpoint at crosswalk to analyze the difference between well-trained and beginner drivers. Three well-trained and three beginner drivers were selected as the examinee. As the result, the well-trained drivers tend to move the viewpoint horizontally for about 3 seconds before arriving the crosswalk. The beginner drivers tend not to move the viewpoint in the same time.

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A measurement method of velocity profile is presented. The bandwidth of the filtering signal of sensor is difficult to be accurately obtained. To overcome the shortcoming, Wavelet transform is used to determine the bandwidth of the filtering signal. RBF neural network is employed to replace conventional image reconstruction algorithms, which has fast and accurate advantages. The simulation experimental results have shown that the velocity measurement method is reliable.

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The number of Japanese consonants are more than the vowels, overwhelmingly. The Japanese consonants are de¯on;ned by ones articulated manner and articulated place, and a phonetic, change of them are quite complex. We remark a transient from stationary signal (like vowel) to nonstationary signal (consonant) which an amplitude of its time domain waveform has not uniform, and try to visualize a behavior of dynamics of some Japanese consonants in phase-space. A Recurrence Plot (RP) imaging analysis is surpassing method where we confront with non-stationary (or like) signals. In this report, we try to analyze particular signals in the between C-V (Consonant-Vowel) phonemes through using the RP analysis. As a result, we can show a quantitative measure from phase-space geometry of some Japanese consonant.

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This paper describes a new method for the sound source localization, where dual sound sources simultaneously exist. While conventional array processing methods require the frequency decomposition as pre-processing, our method estimates the directions of sound sources with higher temporal resolution, directly from the original signal and its spatio-temporal derivatives. We show an algorithm for dual sound source localization and a fabrication of the microphone array system.

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We think robots that move in rubble can approach a sound source by tracing a sound wave propagation. It is necessary to determine a sound wave propagation direction for doing these processes. In this report, we propose the theory and systems for determination of a sound propagation direction. Further more, we confirm that it is possible to trace a sound propagation and approach a sound source in a labyrinth that is model of rubble.

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The authors previously developed an on-line length measurement system for pipes with closed ends by making use of the stationary waves in the pipes. The system adopted sound pressures and their derivatives of several modes of the stationary waves as the state variables of a linear dynamic system and reduced the length measurement to a parameter estimation problem, and thereby realized a highly accurate real-time pipe length measurement. This paper presents a new length measurement system for pipes with open ends.

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This paper presents our proposed acoustic signal analysis tool which can analyze given time-based signals on the musical temperament scale. The prominent feature of this tool is producing high-precision MIDI codes, which reproduce the similar signals as the given source signal using a GM-standard MIDI tone generator. In this paper, we are focusing on its recently developed frequency analysis processing.

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In land mobile communications, it is an important subject to remove intersymbol interference(ISI) and cochannel interference (CCI). In [1], each path is separated using a multistage constant modulus (CM) array, and path diversity reception is performed. In this paper, we use least square combining instead of maximal ratio combining in order to improve bit error rate.

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The placement of the piezoelectric actuator and the H₂ control system in a smart structure are simultaneously optimized by genetic algorithm to achieve an enhanced vibration control performance. Efficient optimization algorithm based on a two-step procedure is employed in the simultaneous optimization, in which the optimal piezoelectric placement and state feedback controller are obtained by genetic algorithm at the 1st-step and then the dynamic compensator for the output feedback is reconstructurcted at the 2nd-step of the optimization. It is verified by some applications with a plate structure and a magnetic disk drive that an enhanced performacne for the vibration suppression can be achieved by the presented optimal design.

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This paper is concerned with structure/control design integration. We propose a method of structure/control design integration based on two finite frequency properties, FFPR (Finite Frequency Positive Real) property and FFHG (Finite Frequency High-Gain) property. We then apply the integrated design methods based on the matrix inequalities to the design of the profile of piezo-electric film for a smart structure to demonstrate the applicability of our design method. The validity is confirmed by both the simulation results and the experments.

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Technology of smart structures is introduced in the flexible-link system to conduct the vibration control. The smart flexible-link is composed of the two flexible-links and the piezoelectric films which have the sensor/actuator function for itself. An approach for hybrid control of motion and vibration is proposed, in which a large magnitude and slow vibration is controlled by the servomotors and a minute vibration is controlled by the piezoelectric film actuators. The motion and vibration controller for the servomotor is designed with the mixed H₂/H_∞ control problem and the vibration controller for the piezoelectric films is constructed by a direct velocity feedback, resulting in the enhanced performance on the motion and vibration control.

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