We proposed a new laser ranging technique using the correlation of chaotic modulation in the previous paper. In this paper we have described the preliminary experiment for ranging using a chaotically modulated laser diode. Chaotic signal was produced by R, L and diode circuit. A visible laser diode was modulated by this signal. Chaotically modulated laser was divided by a beam splitter. One beam was directly detected and the other one was detected via an optical fiber having effective length of 50m. We can measure the delay of beam by taking the correlation of two detected signals. When the modulation of signal was 2MHz, error in the round-trip path length was 0.6m in one measurement.

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In this paper, a new approach to the precise orbit determination problem that is applicable to deep-space missions is presented, in comparison with the conventional orbit determination system using RARR (Range And Range-Rate) data. In this approach, ΔVLBI (Delta Very Long Baseline Interferometry) data, which is acquired by the VLBI spacecraft, are employed together with supplemental one way range data. This technique is applied to a typical Marsian mission by means of computer simulation. And significant enhancement of precision in the orbit determination is demonstrated when compared to the conventional RARR method.

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This paper proposes the measurement principle of a sound source direction in the three-dimensional space. Such kind of differences like the transferring time, phase shift, and level of the sound wave are treated for the measurement in general. Our approach is to use the differences of sound levels by taking the advantage of unidirectional characteristics of the condenser microphone's sensitivity so that the direction is obtained by the simple signal processing. Basically the minimum number of the microphone set is four for composing a tetrapod arrangement. Formulation of the relations among the differences of the sound levels is shown. Also, the logical processing is introduced to remove the affect of the microphone's backside undesirable irregular sensitivity. The calculation procedure for determining the direction is extracted, and experimental results are shown to verify the validity of the measurement.

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For acoustic measuring of gas temperature and flow, firstly, a processing method for microphone received signal based on the matched filtering with the pre-whitening to the AR modeled noises achieves good performance through identifying the time-of-flight under noise contamination. Then, the PRK (phase reversal keying) of the M-sequence appears to be proper for the testing signals that are sent into the object. Finally, this system has been validated through experiments.

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An oil-free, capacitance-type micro pressure sensor is developed using micro-machining and direct-bonding techniques of single crystalline sapphire. It consists of pressure-sensitive and dummy capacitors fabricated at the center and periphery of the sapphire diaphragm, respectively. Ratiometric signal processing between the two capacitors is used to cancel the effects of temperature and relative humidity. Theoretical analyses and performances of a prototype sensor show that the nonlinear capacitance change of the sensor is well approximated by a quadratic function of an applied pressure and measurement error can be reduced to 9×10^-3% FS by three-point calibration in the pressure range from 0 to 500mm H₂O. Errors due to temperature and relative humidity stay within 5×10^-2% FS in 5°C to 45°C and 10% to 90% RH range. These performances are quite satisfactory for practical applications.

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This study describes a system for analyzing drivers' sight-lines. The sight-lines were calculated from head movement and eye movement. Rotational angular velocity sensors measured the head movements in the system we used in this study. The eye movement was measured by an eye mark recorder. The relation between the head and eye movements was observed. We selected 3 conditions, which have significant effects on the sight-line in driving. These conditions were straight driving, right lane change and left lane change. All the conditions of driving were legal speeds on an expressway. The sight-line movements in straight driving were less as compared to lane changing. The ratio of sight-line angle to head movement angle were defined. The effects of these 3 factors on drivers' share of the head movement were analyzed with multiple regression analysis. This result suggests that sight-line represents a specific characteristic of a driving situation. The measurement system for sight-line can be applied to evaluate safe driving.

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In this paper, an exact reconstruction of the state is shown to be done using a finite past input-output data. This means that the input-output relation of the reconstruction system is given, which is named as the reconstructor, and it is shown to be a finite settling observer. A transfer function of the linear functional observer is obtained by the similar method to the reconstructor design.

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Periodic stimulation sometimes stabilizes mechanical systems dynamically. we have investigated a virtically-driven inverted pendulum from a view point of such a dynamic stabilization. First, the stability of the pendulum by the period input is analyzed, and it is shown that the system becomes the parametric excitation system, when period input which modulated the amplitude is added. Next, it is theoretically shown that the pendulum can be asymptotically stabilized, when the amplitude of the input is modulated in the timing which suppresses the parametric excitation. This timing can be realized by modulating the amplitude by the nonlinear feedback which consists of angle and anagular velocity of the pendulum in period doubling of the motion of the pendulum. Finally, the result of verifying the effectiveness by the real machine is shown.

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The control system design method for the controlled object having such a higher order lag element and a dead time element as used in general for the process control system is treated in this paper. Two types of the transfer function with the real order element are used in the control system design method. One is the transfer function of the controlled object approximated the real order lag element and a dead time system to a higher order controlled object. The other is the transfer function of the compensator with the real order phase lead-lag element proposed previously to control this controlled object. The principle of the design for the system composed of these elements is based on frequency characteristics. In this design, parameters of the compensator for a given phase margin, a gain margin and a peak gain in Nichols chart are intended to decide.
The derivation of parameters of the compensator to satisfy specifications of these frequency characteristics is described, and then the property of the control system is confirmed by the transient responses. From results of the unit step response and the consideration to specifications of the system design, a suitable range of the parameter of the compensator is researched in detail. And then a suitable combination of the peak gain and the phase margin is obtained for a given specification of the frequency characteristics. The usability of this control system design method is appreciated through some examples.
Moreover, the application of the principle of this controll system design method to the control system using the most general PID compensator has shown.

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A stabilization fuzzy controller is proposed based on the SIRMs (Single Input Rule Modules) dynamically connected fuzzy inference model for parallel-type double inverted pendulum system. The controller takes the angle and angular velocity of the two pendulums and the position and moving velocity of the cart as its input items, and the driving force as the output item. The method of determining each SIRM and each dynamic importance degree according to control feature of the pendulum system is shown. It is made clear that by using the SIRMs and the dynamic importance degrees, the controls of the two pendulums and the control of the cart are done in parallel, and the priority orders of the three controls are automatically adjusted according to control situations. Control simulations are done to show the effectiveness of the proposed fuzzy controller.

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Master-slave teleoperation system has been used to assist the operator to perform complex and uncertain tasks in space. The system consists of master robot with fixed base located in space station or on the ground and slave robot floating in space. In this paper, the analysis and design of master-slave teleoperation in space are discussed. A master-slave control system that ensures accurate tracking of slave robot upon the master and the stabilization of slave robot's base is proposed. The validity of proposed scheme and performance of system is confirmed by simulations and experiments.

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A coevolutionary genetic algorithm (CGA) that effectively samples and integrates schemata using partial fitness functions is presented. A fitness function is transformed into partial fitness functions having the same schema-sampling ability as the original fitness function. The binary-valued chromosome of the evaluation individual expresses the partial fitness function and is used to evaluate object individuals.
Through competition between the object population and the evaluation population, the fitness of object individuals is defined as the number of evaluation individuals from which the object individual is received. Conversely, the fitness of evaluation individuals is defined as its inverse function. Thus, exploitation of new schema proceeds in, preserving the existing schema.
Ideal partial fitness functions, which can decide the existing of schema, are applied to the royal road problem and two-bit problem. Markov chain analysis is used to evaluate the best performing CGA for each problem. The analysis results confirm that the CGA is effective at solving deceptive problems and that the CGA is not greatly influenced by mutation of the evaluation individual.
The selection of partial fitness functions and the effectiveness of CGA are studied with respect to design problems in neural networks. If partial fitness functions are selected to be decision functions of the coincidence between the partial set of outputs and corresponding true outputs, then execution time for finding the optimum solution to the 4-2-4 encoder decoder problem and 4 neuron blinker problem can be shortened by 2.0% and 15.3% respectively, compared to the simple GA.

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In this paper, measurements of the oil film pressure at piston seals in pneumatic cylinders are made in order to confirm the influence of the pressure distribution on friction characteristics. Experimental results show seal friction force principally depends on speed and lubricant pressure distribution under hydrodynamic lubrication.

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This paper is concerned with stabilizing dynamic feedback control of general nonlinear systems. Control inputs of velocity type are utilized as dynamic feedback control. Two dynamic feedback laws which are proposed can globally asymptotically stabilize general nonlinear systems.

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We propose a method for a mobile robot to generate by itself an environmental map including character information of signboards. The mobile robot with a camera and a distance sensor wanders in an indoor passage environment. An environmental map consists of landmarks and distance information. Signboards in the scene are extracted by image processing based on general features of characters and their string. We conducted experiments and obtained satisfactory results confirming the effectiveness of the proposed method.

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In this paper, an improved decoding procedure with embedded heuristic rules is proposed to generate better active schedules in applying genetic algorithms to a scheduling problem of a metal mold assembly process which is modeled as a large-scale jobshop with additional constraints. An experiment result shows that the proposed algorithm outperforms the algorithms proposed previously and gives better suboptimal solutions for real data.

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