A reference function for JPt100 thermometers specified by the Japanese Industrial Standards, JIS C 1604 and JIS C 1606, is proposed based on the International Temperature Scale of 1990 (ITS-90) and a simple calibration method for JPt100 thermometers is discussed combining the reference function with a linear deviation function. It is pointed out some JPt100 thermometers have a high potential for such accurate as a few mK thermometry. The coefficients of the Callendar-Van Dusen's function, which is another conventional reference function of platinum resistance thermometers, are determined based on the ITS-90 and the function is compared with 3rd and 4th order polynomial functions of temperature.

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A new type of mass-measurement system under weightless conditions is proposed which uses a dynamic vibration absorber as a measuring device. In this system, an object to be measured is fixed to a rotating table (rotor) at a distance from the rotational axis. Since it makes the rotor unbalanced, a centrifugal force whose amplitude is proportional to the mass is generated during rotation. It works as a harmonic excitation and forces a structure supporting the table to vibrate. However, a dynamic vibration absorber attached to the structure is tuned or controlled to reduce the vibration to zero. When the structure does not move at all, the absorber mass vibrates in such a way that the product of the mass and the displacement amplitude is equal to the amount of unbalance, that is, the product of the mass to be measured and its distance from the rotational axis. Therefore, the mass of the object is determined by measuring the displacement amplitude of the absorber mass. In this study, the principles and features of the proposed mass-measurement system are investigated. Experiments are carried out with a developed apparatus having an active dynamic vibration absorber. This apparatus can perform measurement at various rotational speeds because the absorber's natural frequency can be easily tuned by a feedback parameter. Experimental results demonstrate the feasibility of the proposed mass-measurement system.

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Force measurement of the micro objects is very important for micromanipulation. For high accuracy, stiffness of the finger tip can be reduced for force measurement. However, it is not suitable for manipulation. So we consider to evaluate the stress on the micro structure to measure the force. Advantage of force measurement based on stress information comes up when the structure is miniaturized. This can be shown by the scaling analysis. From this reason, we propose a new force measurement and micromanipulation method using the Laser Raman Spectrophotometer. We design a micro gripper that employs the proposed force measurement method. We show experimental results of force measurement with the analytical evaluation to explain the effectiveness of the proposed system.

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This paper describes about a new method for reconstructing a shape of a skin surface replica from three shading images taken with three different lightings. Since the shading images include shadows caused by surface height fluctuation, the conventional photometric stereo method is not suitable for reconstructing its surface shape. In the proposed method, the evaluation function of the surface shape is defined in consideration of the effects of shadow, then the shape is reconstructed by optimizing the evaluation using simulated annealing. The experiments to reconstruct the shape from synthesized images and real images demonstrate that the proposed method is effective for shape reconstruction from shading images which include shadows.

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In order to weave textile based on textile samples, weaving information on the textile's weaving design and the placement of the stripe patterns must be obtained. In this paper, we will discuss a method for extracting the textile's weaving design through the use of machines with the objective of automating a part of the textile design process. Textile designs are built with patterns on the textile's surface by the placement of variously colored warp and weft threads. Consequently, the features of warp and weft threads are always continuous in the warp and weft directions. Therefore, warp and weft threads are distinguished by using two types of band-pass filters, limited in the lengthwise or widthwise direction in the spatial frequency domain. Furthermore, a method for extracting the textile's weaving design with the use of band-pass filters focusing on the frequency is proposed. When extracting the textile's weaving design, this method is not concerned with individual colors and features of each thread but are concerned with the use of two types of band-pass filters considered features of the textile's weaving design. This method is simpler and more efficient than earlier methods.

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This paper shows the several robust control system designs for optimal tracking servo-system with trajectory following and discusses the following desired trajectory and robust performance of each robust control design method. Three robust control design methods we discuss in this paper are based on optimal tracking control design method that has two-degree-of-freedom consisting of feedback (FB) and feedforward (FF) control systems. We call these control design methods “robust optimal tracking control”. First robust optimal tracking control design method is designed by H² control design method that can control the controlled variable in limited frequency range. Second one is designed by H^∞ control design method that deals with the mixed-sensitivity problem. Third one is designed by sliding mode control design method that gets the ideal control property through the state of the control system is constrained in the hyperplane changing the control structure in both sides of the hyperplane.
It is desirable to be clear the difference of the control performance in robust control methods. We discuss the difference of control performance by simulations and H² norm. Simulations are done by four patterns from the points of view of following desired trajectory and robust performance. By simulations, sliding mode optimal tracking control follows the desired trajectory without the smooth of desired trajectory and isn't influenced by disturbance comparing with other robust optimal tracking control methods.

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The passivity theorem says that the feedback interconnection of a strictly positive real (SPR) system and a passive system is L₂-stable. But it is an open question whether the feedback interconnection of a pseudo-SPR system which has weaker condition than SPR and a passive system is stable ar not. In this paper, we prove that the feedback interconnection of a pseudo-SPR system and a passive system is asymptotically stable in the Lyapunov sense. Two well-known time-invariant passive systems are considered.

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In this paper, we study an inverse system that reconstructs approximate values for inputs in a generalized linear system.
First, we discuss integral indices so that the approximate inverse system is proper. Then we show that outputs can be devided into two groups according to their roles. One is used for constructing the inverse system and the other for reducing the order of the inverse system.
Finally, a new designing procedure is proposed for the low order approximate inverse system. This procedure is also applicable to generalized linear systems.

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Observers should exist under some conditions for generalized state space systems having unknown inputs. Such structural conditions are discussed in this paper. New sufficient conditions are derived by using the graph-representation for linear descriptor systems. From the point of view of constructing an observer for the system with unknown inputs, a procedure for selecting detector positions is presented.

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This paper presents the effectiveness of the computer based discrete time sliding mode control algorithm to compensate the attitude deviation of the main body of a free-flying space robot, which is caused by both the motion of manipulators on it, and the disturbance caused by some work such as capturing a flying target or throwing a equipment by it's arm. The controller design methodology using discrete time sliding mode control algorithm is developed. And the performance of it is compared with those of current discrete time PD control algorithm and continuous time sliding mode control algorithm by numerical simulations and a simplified model test. The discrete time sliding mode control algorithm causes no chattering that is often observed in the case of the continuous time sliding mode control algorithm. It is clarified that the discrete time sliding mode control algorithm is the highest performance and robustness among them.

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There are a large number of problems in systems and control that can be formulated as semidefinite programs: minimize a linear function subject to linear matrix inequality constraints. In this paper we study the effect of perturbations in the semidefinite program on the optimal solution and the optimal value function. A new form of complementarity conditions is proposed and the first-order partial derivatives of the optimal solution and the optimal value function with respect to parametric variation are explicitly expressed by the problem data and the optimal solution. Furthermore, the above result is applied to sensitivity analysis of control systems with parametric uncertainties.

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The head positioning servo control of magnetic disk drives has been required to achieve both precise positioning and fast access. In order to meet these requirements, the Mode Switching Control (MSC) structure that includes several different structure controllers and switching functions has been widely used. In the MSC, each servo controller can be designed optimally, so the remaining issue is “switching.”
The MSC is a kind of Variable Structure Control System, but the switching is in one direction. This means that the servo mode is handed over from one to the other during a single servo action. So when the mode is switched from seek mode to track following one for example, this switching time is an initial time for the track following mode. As a result, the Initial Value Compensation (IVC) which is a method that considers the initial states, can be applied. The authors previously proposed the design method of this IVC and showed its effectiveness using disk drives servo control.
In this paper, we propose a new IVC method using additional input. When the servo mode is switched, an additional input which is an impulse response of initial values of the plant state variables, is added. The transfer function of the impulse response can be designed in order to not only cancel undesired poles of the transfer function from initial states to head position, but add desired poles as well. Therefore the transient response after mode switching can be much improved from the previous method. Also this IVC never influences the stability and sensitivity of the closed loop. Several experimental results show the effectiveness of this method.

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We present a new robust minimax design method of the I-PD controller based on the generalized ISE criterion with a penalty of the derivative of the manipulated variable. It is shown that the generalized ISE is a weighted sum of the two ISE's for the I-PD and PID controllers. A genetic algorithm based method is developed for solving the minimax problem. For the first and second order systems with a time-delay, we show that the robustness of the closed-loop responses to parameter variations is greatly improved over the earlier designs based on the ISE criterion.

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A new sliding mode controller for manipulator driven by artificial muscle actuator is presented which guarantees an asymptotic tracking of a desired trajectory. Based on the non-linear characteristic of artificial muscle tube, a dynamic model of artificial muscle actuator is formed and exploited to derive a full dynamic model for the manipulator system. By applying the sliding mode control technique and the presented full dynamic of manipulator, a robust tracking control approach is developed for such manipulator system. The controller consists of a feedforward control part and a novel sliding mode control part, so that the tracking error of the closed-loop system, which is composed by the robust controller, will converge to zero in a finite time. The asymptotic stability of the closed-loop tracking system is proven by means of the Lyapunov method, and it is also guaranteed that the control input is bounded. Some numerical case studies are provided to illustrate the performance of the control approach.

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This paper is concerned with the design of discrete time sliding mode controller to sensorless flexible rotor-magnetic bearing systems (SFR-MBS). The plant dynamics, consisting of actuator dynamics and flexible rotor dynamics, are described. A variable structure system (VSS) disturbance observer, with which the state vector and disturbance can be estimated simultaneously, is investigated to compensate the mismatched disturbance. A new discrete time sliding mode servo controller, which can attenuate the chattering phenomenon, is proposed by using this VSS observer. The usefulness of the proposed controller is demonstrated through the computer simulations for a sensorless flexible rotor-magnetic bearing system under external disturbances and modeling uncertainties.

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In global optimization, there exist many problems which have multiple global solutions. In this paper, Multi-Trajectory Random Search Method with Territory Competition is proposed for such problems.
In the conventional Random Search, the global optimal solution is searched by only one trajectory. In the proposed method, the multiple global solutions are searched by multiple trajectories.
In order to find multiple global solutions, the concept of territory competition among multiple trajectories is introduced. Finding every global solution is guaranteed under some mild conditions and its proof is given.
The proposed method is applied to find the solutions of simultaneous nonlilear equations. The method is shown to be very powerful and can find every solution at one trial for example problem. The method is compared with the other methods and its superior points are shown.
The proposed method is very effective, and its application to many problems is promising.

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It is considered that KANSEI is an important human characteristic, and it affects on human motion. However, the relationship between KANSEI and human motion have not been discussed. So, this study aims to clarify the effect of KANSEI on human motion. In this study, “KANSEI” is defined as follows: “KANSEI is one of human abilities to get, process and evaluate information, like sound and color, that consists of many parameters”. Violin playing is selected as an example of human motion strongly affected by KANSEI. This paper describs a model of planning of violin playing and the results of experiments based on the model.
The model is divided by two phases. One is task planning and the other is motion planning. In the work planning, notes information and KANSEI information are derived from music notes. Bow force, bow speed, sounding point and fingering are derived from them. In the motion planning, motion trajectory of the right and left arms and fingers is determined from the playing information. As a result, the sound is produced through playing a violin. From above consideration, it is assumed that KANSEI information affects the task planning mainly.
In the experiments, scales were played by three professional violinists to clarify the effects of KANSEI information. Eleven timbre describing terms like “bright”, “dark” in Japanese were given to them as KANSEI information. Bow speed, sounding point and fingering are measured by videotape, and bow force was measured by strain gauges attached to the bow.
From the analysis of the data, it is found that according to the change of KANSEI information, bow force and sounding point change, but bow speed does not change.

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This paper introduces a new approach for recognizing cursively handwritten isolated Arabic characters. The approach is based on an active analysis of human handwriting movements, which was proposed and discussed extensively by the authors in a previous paper1). The handwriting process is modeled through autoregressive moving average (ARMA) model. Model Reference Adaptive Control System (MRACS) theory is applied, in order to extract control pulses of the handwriting movements. The control pulses, which describe in details the handwriting movement's behavior, are then used for recognizing the shape of the cursively handwritten character. Although the presented approach is proposed for recognizing handwritten Arabic characters, it can, however, be applied equally well to actively recognize any other cursively handwritten scripts.

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In this paper, a new optimization method named Likelihood Search Method (L.S.M.) is proposed for searching for a global optimum systematically and effectively in a single framework, which is not a combination of different methods. The L.S.M. can be applied to differentiable objective functions. The L.S.M. can realize the intensification and diversification of the search based on an idea that the searching for variables is intensified where a likelihood of finding good solutions is high, on the other hand, the searching for the variables is diversified where the likelihood is low. The L.S.M. is basically Random Search Method (R.S.M.) but utilizes gradient information. The likelihood of finding good solutions is defined by the norm of gradient. In case that the norm of gradient is large, this means the likelihood of finding good solutions is high, that is, it is very likely that a better solution exists in the vicinity of the current solution. On the other hand, In case that the norm of gradient is small, this means the likelihood is low, that is, we do not expect that a better solution is near the current solution. Therefore, in case of high likelihood, the search is done within a short range in the opposite direction of the gradient vector. So, intensified search can be realized. On the other hand, in case of low likelihood, the search does not much depend on the gradient; the range is wide, and the direction includes even those which make the objective function worse. So, diversified search can be realized. From the simulation results of minimizing a complicated multi variable nonlinear function and controlling a nonlinear crane system, it has been clarified that the L.S.M. is superior to both the Gradient Method and the R.S.M..

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A new concept on the degree of credibility of parameter value variations (DCPV factor) is proposed in this paper to solve the problem that on-line monitoring and failure diagnosis of rolling element bearings are affected by monitoring parameter value variations caused by the intrusive vibration signals. Using the factor of the degree of credibility and the basic principle of the expert system, an on-line monitoring and diagnostic method of rolling element bearings with AI is developed. The technique enhances traditional vibration analysis and provides a means of automating the monitoring and diagnosis of vibrating device.

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This paper presents a maximum search procedure using a combined global priority strategy with local peak estimation for two-dimensional multimodal unknown functions. The functions are supposed to be continuous but need not to be smooth. An efficient sequential algorithm is presented for arrangement of search points, using search subdomains with three adjoining sampled points and their nested division. The search procedure is composed of two stages to select the suitable sampling strategy according to different global informations. In the first stage, the subdomain largest in length is selected. In the second stage, the subdomains in which a local maximum exists are searched. Measures of error for local maximum search are introduced to check if a local maximum has converged to a specified accuracy or cannot be the global maximum. The effectiveness of the algorithm is validated by computer simulations for some example functions and comparisons with previous results by another deterministic, sequential algorithm which uses interpolation techniques for global search.

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This paper describes what kind of tactile stimulation is effective to perceive speech signals in order to design an optimal tactile aid. The results showed that non-vibratory swept patterns like Braille are more practical than vibratory patterns for long time use.

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This paper presents a prototype of an image based compliant tactile sensor for soft fingers. The sensor measures an indent of the rubber skin using stereo vision. And this sensor detects features of a contacting object.

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This paper presents a smooth static state feedback control law for the stabilization of two input, driftless, chained nonholonomic systems. It is shown that exponential stability can be achieved except some specified initial state.

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