The purpose of this paper is to realize the dexterous manipulation by a robot hand with multi-sensor processings and control. Here, the shaping of a plastic object to the objective shape is treated as an example of dextrous manipulation task. The four-fingered hand mechanism and the sensing system of the robot hand for the shaping task are discussed. A force sensor and a matrix tactile sensor are used to detect the characteristics of the object and the shape of the object in the robot hand. For the processings of multi-sensor information, the concept of sensor fusion is adopted.
By the experiments of clay shaping to the shape of sphere or cube, the effectiveness of the proposed multi-sensor control method is confirmed.

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Recently we have to treat very small objects in various fields like as the biological field, the medical field and the industrial field. Especially, to do this operation well, we should recognize the tactile sense of the target. But, due to sparseness of our finger tactile sensor, we cannot have such small tactile feeling. Thus we need some intelligent tools to treat such small targets. This paper describes possibility of taclite recognition of micro-targets with a micromacro master-slave manipilator. The micro-macro master-slave manipualtor proposed here has a bilateral position and force feedback loop with proper scalling factor. By using this manipulator, we can recognize the softness of small particles of various materials.

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This paper deals with a control method for a man-robot cooperative hydraulic manipulator, and evaluation of its task performance. The man-robot cooperative system is aimed at cooperation between a human operator and a robotic system. The control system for the man-robot cooperation manipulator is designed for the human operator to teach the motion of the manipulator directly. The control system is also designed to carry up a heavy payload and we can specify both operational force (human force) amplification ratio and maneuverability of the manipulator. We apply the concept of the man-robot cooperative work to a hydraulic manipulator. In the experiment, we show the effectiveness of applying a hydraulic cooperative manipulator for handling a heavy object.

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This paper proposes an alternative control algorithm for a scaled telemanipulation system based on a task-oriented virtual tool. In the algorithm a telemanipulator is controlled so that it has aa virtual tool dynamics which is designed appropriately for a given task. The dynamics assists a human operator as a tool and the operator can execute a task easily with the tool. In addition, the motion and the force relation between the master and the slave can be specified freely by using two scaling factors; a motion scaling factor and a force scaling factor. The stability of the resultant system is analyzed based on the passivity of the system and the total stability is guaranteed for a human operator and a passive environment with unknown dynamics. The proposed control algorithm is experimentally applied to a telemanipulator. The experimental results illustrate the validity of the algorithm.

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The vibration problems related to living bodies have so far been studied from the perspectives of engimeering, physiology, and psychology. This study shows the relationship between vibratory sensibility and temperature in the living body.
Psychological experiments were carried out by using the vibrometer of an acoustical calibration apparatus in sine, triangular and square waves. The sensibility-threshold measurements were made using 30_??_700 Hz sine waves, 30_??_700 Hz triangular and sawtooth waves, or 30_??_250 Hz square waves. Each of ten subjects was kept seated. The average value of the vibratory levels, varied by ascending and descending steps, was taken as that of the threshold. As the vibrometer in the apparatus used makes a noise at frequencies greater than 250Hz, it was masked from the subject by presenting him with a different noise.
The threshold curve for square waves was lower by 12.3 dB than that for sine waves at about 30 Hz. The threshold curve of the 26°C sine wave was lower by 10 dB than that of the 58°C sine wave vibration near 200Hz. At frequency stimulation higher than 120Hz, as the temperature of thecontact point was lowered, the anplitude threshold increased and the frequency at which the threshold curve was at a minimum shifted to a lower frequency.
In addition, a model of the vibratory sensibility system was constructed by electronic circuits.

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Various types of trajectory techniques were considered in order to find the global minimum by means of the numerical integration of a differential equation. As new one of such techniques, the trajectory technique based on the higher order differential equation model is presented for continuous optimization problems with variables constrained on the closed interval _??_0, 1_??_. In order to realize the new differential equation model in neural networks, the new type of neural networks with the multi-layered and feedback structure is proposed. Simulation results for the neural networks based on the second and the third order differential equation models show global convergence.

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It is important to consider a stabilization problem for a large scale power system. In this paper, we use a dynamic compensator based on observer theory such that desired poles are placed for a closed loop multimachine power system. Since dimension of the system is large, it is difficult to apply a conventional dynamic compensator method to an excitation control problem for a multi-machine power system.
We introduce the homotopy method to solve fundamental nonlinear equations which are required for observer synthesis. To show the effectiveness of the proposed method, we consider an excitation control of generators for a multi-machine power system.
From the simulation result, it is shown that the present method is useful to stabilize a mufti-machine power system.

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This paper presents a magneto-optical head that corrects for astigmatism by rotating an inclinated transparent plate glass between a laser and collimating lens. Through astigmatism-correction, the best focus offset point for reproducing the carrier-to-noise ratio (CNR) coincided with the best point of tracking error (TE) signal level. For designing the inclinated glass plate, the thickness and the inclination angle were optimized in terms of wavefront aberration. A recording density of 0.34μm/bit was confirmed with a numerical aperture of(NA)=0.55 and 680 nm-laser in good condition of focus offset for both TE signal level and CNR.

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The present paper is concerned with the conditions under which for a familiy of polynomials, every member has a given number of roots in the open left-half plane and the other roots in the open right-half plane. Simple criteria for such root distribution invariance are provided for some families of polynomials, including the interval and diamond polynomial families. Using one of them, some extreme point results are presented for the Hurwitz stability of the weighted diamond family.

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Noise reduction effect using decoupling capacitor with series resistor was studied. It is well known that the decoupling capacitor is a familiar noise reduction technique on a printed circuit, and its effect is limited at high frequency by some parasitic inductances such as lead, trace and so on. Some capacitors are often connected in parallel for widening its band, but its impedance grows up highly at parallel resonance frequency. In this paper, the effect of the suppression of parallel resonance by decoupling capacitor with resistor is described and the relation between band width and device parameters is shown. The reducion effect is measured and simulated about transmission characteristic and near magnetic field.

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In this paper, we present a retrieval method of drawing image databases. The method is intended to assist retrieval performed by tracing lines in the drawings where symbols and lines describe connections between components. This method is based on the viewpoint transition model which we propose in this paper. In this model, a database retrieval is described as a process of viewpoint transition in the data space. The viewpoint transition is controlled by the rules designed for each application.
This method has a feature that the aim and situation of a retrieval are properly reflected to the results of the retrieval, compared to former methods such as the hyper-link method.
We implemented this method to the plant diagram database which is used as a help to plant control and maintenance. The effectiveness of this method is confirmed in the experiment which is performed supposing the situation that an operator gathers the plant informations to determine the cause of abnormality when a meter detects it.

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This paper presents a rotation invariant neural pattern recognition system capable of recognizing a rotated pattern and estimating its rotation angle. The system consists of two networks, the first and the second networks. The first one is to recognize a rotated pattern and to estimate its rotation angle. Next, the second one is to estimate the rotation angle more exactly. Those networks detect in their preprocessors edge features which are input patterns to multilayered networks. They are not insensitive to rotation. Rotational invariance is achieved in the multilayered networks, which are the three-layered networks. In the first network an output layer is divided into two different parts. One is to recognize an input pattern to be invariant to rotation and the other is to estimate its rotation angle. The second network can compute smaller rotation angle by using the popular three-layered network.
In the paper, it is shown that, by means of computer simulations on a binary pattern recognition problem, the proposed system is able to recognize rotated patterns, and further can estimate their rotation angle.

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This paper deals with an optimal production ordering problem for a modified flowshop manufacturing process having multiple machines and a carrier. The carrier carries a product between the machines and the yards. The schedule condition includes the due date and the setup time of each product. The makespan, the lateness, the tardiness, the number of tardy products and the constant rate of production are considered, respectively, as the objective function.
For obtaining a good suboptimal solution, the genetic algorithm (GA) is applied to this problem. Since crossover operation plays an important role in GA, five crossover operations are introduced for this problem. This paper aims at examining robustness of crossover operation, that is, which crossover operation can find a good solution regardless of variation of schedule conditions. Numerical results show that the most desirable operation is the order crossover from this viewpoint.

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