An integrated multi-piezoresistive gauge (IMPG) sensor was designed for differential pressure transmitters. The sensor measures three quantities: the differential and static pressures, and the ambient temperature. Three pizoresistive gauges were positioned on a {110} plane crystallographic silicon diaphragm. The voltage outputs of the gauges were calculated with respect to the distance between a modulus of the silicon diaphragm and its mounting glass die. Numerical analysis revealed that crosstalk between the gauges were occurred when a differential pressure was applied to the sensor. This resulted in elastic deformation of the diaphragm on the periphery. The proper dimensional design and the optimal gauge positioning maximized the output and minimized the crosstalk. The three voltage outputs were combined by a microcomputer to yield a compensated sensor output. An experimental IMPG sensor was fabricated and the compensation scheme was proved to be useful. The accuracy was within ±0.1% of the full scale in the pressure range of ±80kPa. The drift was less than 0.25% for the temperature change of 50°C and was less than 0.2% for the static pressure change of 10MPa.

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The performance of an adaptive system is generally dominated by the adaptive algorithm implemented in it. Therefore it is extremely important in designing such a system to well understand the properties of various algorithms and to select the one meeting design specification best. To do these, systematization of adaptive algorithms and unified analysis of their properties are necessary.
This paper presents a well generalized adaptive algorithm which can systematize the conventional algorithms, and shows an analysis of its properties. This analysis becomes a unified analysis on the properties of the various algorithms. Through the analysis, effects of normalization of integral-type algorithm and effects of attachment of proportional-type algorithm are also made clear.

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VSS identification approach is based on following concept, i.e. while in sliding motion, the switching of control inputs reflects system uncertainties (unknown parameters). Therefore, if there exist some operations that make the information from the switching control inputs be achievable, then the unknown parameters can be accuratlly identified as far as it is capable of selecting suitable identification mechanisms which can fully make use of the available information.
Two different types of VSS identifiers are taken into consideration. The first type uses adjustable model whose structure is similar to that of identified systems. From the viewpoint of control, this type of VSS identifiers may be regarded as direct identifier because the identified system is handled as an open loop. On the other hand, if the identified system is controllable in the sense of VSS (sliding mode can be generated through chosing control inputs), the second type VSS identifier, the indirect VSS identifier, can be constructed according to the linearized system structure while staying in sliding mode. Therefore it can be applied to some nonlinear systems which are not linear in parametric space by general identification algorithms, whereas linear in parametric space when sliding mode is existed.

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In this paper we propose a high resolution spectral estimation algorithm for sinusoidal signals corrupted by white noise. This algorithm could estimate the frequencies of measured signals more accurately than IFA⁹⁾ can do, under the low SN ratio.
For Hildebrand's Prony method, the AR spectral estimation procedure is extended. The proposed algorithm employs the extended Prony method iteratively and then designs a prefilter which has parallel structure by the first order filter with complex coefficients. As a result, the SN ratio of measured signals is increased and the estimation accuracy could be improved.

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Computational algorithms for control of manipulators mounted on a free-flying space robot are considered in this paper. Such manipulators differ from base-fixed ones, because the motion of the satellite body is affected by that of the manipulator. Although the generalized Jacobian or the resolved acceleration control of the space robot was proposed by taking account of the body motion, a large amount of computation Was required to execute these control schemes in 3 dimensional space. We propose here effective algorithms to calculate the generalized Jacobian, the inverse dynamics and the resolved acceleration control for those manipulators. The proposed algorithms are efficient because the recursive calculation is used and the number of computations is proportional to the number of links of the manipulator. The numbers of computation in case of a manipulator with 6 degrees of freedom show that these algorithms are realizable for the control of the space robot.

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For high speed positioning of pneumatic cylinders, rapid and stable acceleration and deceleration are needed. However, it has been difficult to get satisfactory response because of compressibility of air and low damping ratio of the system. Since the piston and the load are driven by the force which is produced by pressure difference between two chambers of the cylinder, higher performance can be expected by applying the control scheme based on pressure control.
In this paper, a new velocity control scheme for rapid motion of pneumatic cylinders is proposed. In many application of pneumatic cylinders, reference positions are known previously and the proper velocity pattern to reach the reference position can be designed. Thus we derive the reference pressure pattern from the velocity pattern, and construct the pressure control system such that the pressure in the cylinder chambers can follow this pressure reference. PD control scheme was adopted for the pressure control system. And the compensation for the effect of the piston motion to the pressure change was considered.
The validity of this control scheme was confirmed by the experiment in which rapid and stable acceleration and deceleration were achieved.

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A photofluidic interface is a new fluidic device which transduces optical control signals to pneumatic or hydraulic control signals. Up to now two kinds of device have been proposed and one of them was developed by B. Hockaday, et al. in 1983. Although this device has the advantage of producing a larger response than the other, the principle of its operation is not fully understood.
In this paper, the static and dynamic characteristics of this type of interface were investigated experimentally and theoretically. A He-Ne laser beam of 5∼40mW was focused into the flow in the supply nozzle edge of the device. The following results were obtained: 1. By the experiment with air or water as a working fluid, the measurement of the temperature change at and around a focal point, and the analytical flow model, it was made clear that the heat generated by light changed the fluid viscosity locally, and this caused a difference in output pressure. 2. The proposed analytical model can make reliable predictions about the effects of focal point, nozzle width, and splitter distance on the relation between optical power and output differential pressure. 3. The frequency response of the interface was measured and the band width was 150Hz.

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Pneumatic drive system is essentially a pressure control system and the response of pressure has to be improved to get better system performance. Since applications of pneumatics to force control and compliance control are expected, it is important to clarify the characteristics and the control scheme of the pneumatic drive system with considering the role of pressure.
This paper describes the double structured feedback control system for the position control of pneumatic drive system in which the variable gain pressure control system is included as an important internal system. In this system, the PD pressure control system with variable gains is constructed first. These variable gains compensate the effect of piston position by which the dynamics of the pressure response changes. Next, the reference of the pressure control system is produced by the proper controller from the error signal of the piston position. And the compensation for the disturbance caused by the fluctuation of friction force is considered and the compensating pressure is added to the reference pressure.
The experiment was carried out and the good position control was achieved. Improvement of positioning accuracy by the compensation of friction force was also confirmed. Thus the validity of this control system was clarified.

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As more and more human-related variables such as preference, subjective decision making, sense of taste or smell, and so on, are involved in the discussion of measurement and evaluation, the theoretical exploration into the foundation for measurement from a broad perspective is becoming important.
One remarkable character of human-related variables can be seen in their binary relationship. Almost always intransitivity appears. For example, from among a set of objects {A, B, C, …}, take a pair of them and ask the evaluator: “Which do you prefer?” (the pairwise comparison). The evaluator may prefer A to B and B to C among many such comparisons. There is often the case, however, when A and C are paired later casually, the evaluator chooses C rather than A! In such a case, the data are represented as an asymmetric directed graph known as “tournament” which has cycles.
Here, we present an analysis of the strongly connected tournament, sometimes too complicated and difficult to analyse. Paying attention to the transitive subsets appearing along a Hamiltonian cycle we discuss how to construct the Hamiltonian cycle along which more transitive subsets apper. Our purpose is, through such graph-theoretic formalization, to provide a theoretical framework to consider the relationship between a local transitivity, and the grobal intransitivity in the course of evaluation.
We use the operation of “addition of a point”, i.e. insertion of a point to a subcycle, and point out two distinct types of insertions: the degenerate insertion and the generic insertion. As a result, some aspect of strongly connected tournament can be featured by the degree of degeneracy.

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Sensor fusion is basic structure of systems with various sensors and actuators to implement functions which can not be performed with a few sensors. In this paper, a general definition of sensor fusion, which can clarify problems of sensor fusion, is proposed. The definition shows that the sensor fusion is conversion into a stable state with consistency. In order to implement the sensor fusion, it is the most significant problem to harmonize requirements of high speed and real time processing and abstractive knowledge processing.
From the viewpoint of this definition, a paradigm of internal model is also proposed. The internal model is an objective model constructed in processing units. It can naturally describe a large quantity of polymodal sensors and actuators so that it can implement flexibility and robustness into the fusion system. In addition, a system, in which realtime signal processing and complicated symbol processing are separated utilizing the paradigm, is also proposed. The signal processing subsystem of the system is constructed with Transputers, which are processors to realize MIMD type parallel processing.
The configuration of the system is described and sensor fusion between vision and pseudo tactile information is demonstrated as a practical sample of the system. Experimental results of sensor data fusion and applicaion to error detection and correction are shown.

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The concept of complex first order system (CFOS) is introduced. The CFOS is an extension of the ordinary first order system to complex variables and coefficients. The CFOS can represent both ordinary first order and second order systems by adjusting its coefficients.
By the introduction of complex response of CFOS, responses to various initial values are shown to be essentially identical for a given system as in the case of ordinary first order systems. And by defining frequency response as a complex Fourier transform of the complex impulse response of CFOS, frequency response for different initial values are shown to be essentialy identical. The CFOS has one pole while ordinary second order system has two conjugate poles.
Correspondence of real physical system and CFOS is discussed and the method of determining parameters of CFOS whose response has real part which resembles best to the given waveform is shown. This method is based on the fact that when an given waveform is supplied inversely to the CFOS as an input signal, then the output waveform becomes cross-correlation function of the input signal and the impulse response of CFOS.

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The quality of master arm design influences considerably the maneuverability of masterslave systems. Although several examples of master arm design have been presented so far, the way to design was somewhat intuitive. In this paper, a quantitative measure of manipulating ability of master arms is proposed. This measure which is obtained by extending the concept of dynamic manipulability considers operator dynamics since operator dynamics can't be neglected when he manipulates a master arm. We point out that the maneuverability of master arms depends on not only the magnitude of the manipulability value but also the distribution of the manipulability value and the directional property of the manipulability ellipsoid in the work space. Then we propose a quantitative index to evaluate these properties by evaluating the similarity of dynamic manipulability between when the operator manipulates the master arm and when he has no load. Several types of master arms are evaluated by the proposed measure. It is shown that relative position of master arms to the operator is an important factor of the manipulability as well as the master arm design.

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In this paper, a set of curve descriptors for representing and classifying very short curve segments according to their circularity are proposed. First, we show a degenerative gradient covariance matrix of a curve segment indicates it can be fitted by some circular arcs without knowing its radius. After deriving dimensionless and normalized equations and adding a noise suppressing characteristic to them, we obtain two basic operators which evaluate the desimilarities to 1) arcs whose centers are locating at an origin (NON-CIRCLE) and 2) arcs of arbitrary locations (NON-ARC). Their complementary operators which respond to 3) centered arcs (CIRCLE) and 4) non-centered arcs (ARC) are also defined. Basically, they are seen to measure the similarities between a given line segment and two types of circles noted above. By a theoretical analysis, however, the NON-CIRCLE and NON-ARC operators are shown to act as the singularity detecting operators which respond maximally on tangential and/or curvature discontinuities in an invariant manner to their strength. By using computer generated curves and actual TV image data, the proposed operators are examined under noiseless and noisy conditions.

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This paper proposes a new sensing method of small differential pressure by use of magnetic fluid. When a magnetic fluid plug is used as a leak proof seal, its characteristic is analyzed with the Bernoulli equation. The result shows the differential pressure is a function of magnetic field. The authors put a magnetic fluid plug to seal a small pressure difference. They measured the displacement of the magnetic plug caused by the pressure difference. Their experiment shows above mentioned displacement could be a measure of the differential pressure.

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An analytical method for obtainning the natural frequency of two types of the gaseous pressure probe (orifice-cavity type and linecavity type) is presented and the results are experimentally evaluated. A design procedure of the probe is also presented.

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We have already compared sharpness of the stability robustness measures so far proposed for the state-space model of linear continuous-time systems. Now, several robustness measures for discrete-time systems become available and the parallel attempt to the continuous version, the comparison among them, is made in this paper. The result obtained makes it possible to arrange all the considered measures in order of sharpness.

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This paper is concerned with a new method of designing the state feedback control law for linear discrete-time systems. A discrete type selectable turn over design method is proposed. This method is developed on the idea to locate all the closed-loop eigenvalues in the desirable stability region. This method utilizes the geometric relation between openloop eigenvalues and corresponding closedloop eigenvalues. The effectiveness of this method is demonstrated by experimental tests.

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This paper presents a new algorithm for solving the Bezout equation for scalar systems with commensurate time-delays. The solution is obtained over polynomials with a coefficient ring of finite Laplace transforms.

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In factory automation systems, it is desired to develop a linear fork mechanism which is in 100kgf load rating. Now, we have successfully developed 2.2s fast fork mechanism with 1.0m/s² acceleration by the experiment.

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