[in Japanese]

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For linear time-invariant discrete-time systems with unknown disturbances and observation noises, optimal numerical design of disturbance observers, which estimate unknown disturbances, is presented. Under the condition that upper bounds of rate of change of disturbances and magnitude of observation noises are known, the observer is designed so that the supremums of absolute values of estimation errors are minimized in the sense of Pareto optimality. Simulation results are given to show availability of the design.

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This paper addresses the state-estimation problem for nonlinear hybrid systems.We apply extended Kalman filter(EKF) and Unscented Kalman Filter(UKF) to nonlinear hybrid system,and verified the effectiveness of UKF.Furthermore,for nonlinear systems with an interval constraint,we apply an UKF base algorithm which uses an interval constraint,and verified the effectiveness of the algorithm.

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[in Japanese]

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In this paper, we describes a knee stretch walking for the biped small-sized robot with servo motors. This biped robot have 1-DOF in spine roll-axis and 2-DOF in each knee. The singular configuration of the robot often is a problem . In addition, the biped robot has to walk near-naturally. By using this mechanism, evasion of a singular configuration and a knee stretch walking can be achieved.

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[in Japanese]

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Humanoid robots have to avoid falling down in various situations. In particular, when a large disturbance acts on a humanoid robot or when the robot exerts impulsive forces on the environment, the fall-prevention problem becomes more difficult because of the severe time constraint. In this paper, a method to avoid falling down with stepping motion is proposed. The effectiveness of the method is also confirmed.

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One of the major problems of humanoid robots is that tasks are limited by the maximum torque of the actuators. This paper discusses a way to perform heavy tasks by a humanoid robot by utilizing impulsive force, own weight, dual arm cooperation for load distribution etc. Excavation is performed by a humanoid robot as an example of heavy tasks to validate the effectiveness of the discussed method.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Laser ultrasound is an effective technique for non-contact generation and detection of bulk waves in specimens. The temperature dependence of the propagation velocity of bulk waves in metals can be utilized to estimate the average internal temperature of the specimen. In this experiment, laser pulses were irradiated on SUS304 and 9-Cr specimens, generating longitudinal waves which propagated inside the specimen. Longitudinal waves reflected from the specimen back wall were detected by a laser interferometer. To demonstrate that this technique is also applicable to specimens in motion, measurement of specimens rotating at 300-600 rpm heated up to 920C inside an electrical furnace was performed. The internal temperature variation during natural cooling of the rotating specimen was measured.

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Two types of temperature measurement systems developed for space use are described. One is the wireless multichannel measurement system that is able to two minutes. The system is consists of sensor modules, a base unit with antenna and a data handling with PC. The measurement of temperature range is from 153K to 392K. And the other is the no contact wide range measurement system with Christiansen effect is that spectral emissivity is unity at the Christiansen wavelength. The system is consists of a thermopile module, a narrow band pass filter with Christiansen wavelength and a dimmer filter. In the temperature range is from 173K to 1500K.

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[in Japanese]

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Neutron resonance absorption spectroscopy (N-RAS) is a method to analyze the kind of nuclide and its dynamics using a pulsed neutron source. Through the analysis of the spectrum of imbedded neutron-absorbing nuclides, the "effective temperature", which coincides with the actual local temperature near and above room temperature, can be determined.

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[in Japanese]

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This report deals with spectroscopic approach to thermal radiation science and engineering of solid surfaces. Topics are on a wide-spectral-range high-speed spectrophotometer, spectral phenomena of thermal radiation, coherency of emitted thermal radiation wave, electromagnetism combined with Planck's theory, spectroscopic diagnosis of temperature and microstructure of surfaces, spectrally-selective functional surface for TPV power generation, from absorption spectra to absorptance spectra, and experimental verification of the Kirchhoff's law on a basis of an electromagnetic wave level.

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In this study, a new device utilizing micro three-dimensional vibration stage is developed to control cell culture. A new cell culture control system with the use of three-dimensional vibration stages is developed to culture while stimulating in the CO2 incubater. Experimental studies have been carried out by using normal human osteoblast. The vibration stage developed, in which doubly L-shaped clamped-free beam type vibrator is utilized, has quite simple structure and is able to sterilize itself easily. The studies have shown that the cell has capability to detect dynamic stimulations and to change its own figure.

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In this study, a new sensor system is developed to detect compliance of cultured cells by using dynamic response of a piezoelectric vibrator. The sensor was integrally controlled by a micromanipulator system, while dimensions and morphologies of the cells were measured by an inverted phase contrast microscope system. Experimental studies have been carried out using normal human osteoblast. The studies have shown the sensor's capability to detect changes of mechanical properties of the cultured cells. Also, the method has shown the relationship between compliance and repolymerization time of the stress fiber.

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Vascular endothelial cells covering the inner surface of capillaries transport various macro molecules by movement of membrane pits called "caveolae". Also, membrane channel called "transendotheial channel" contributes to quick vesicular transport. A recent paper indicates that there exists diaphragm around the neck of the caleolae and channel. The purpose of this study is to clarify the influence of the diaphragm on vesicular transports. First, a system of nonlinear differential equations is derived according to the variational principle. Then the solution is given by shooting method. Next by using the 3-D model of the caveolae, CFD software PHOENICS solves equation of continuity and Navier-Stokes equation, and it provides blood flow over the caveolae with or without diaphragm.

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In this paper, the navigation task is applied to the potential function that we propose. The superiority of this method is shown compared with other method. The specifications that a conventional real machine affected an experiment were improved by having made an actual machine newly. As a result, it comes to be able to innovate the experiment under an environment of simulation. We verify influence on the navigation by experiment with the real robot.

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In this paper, we are aimed at stable walking in rough way for an autonomous quadruped robot using reactive behavior. We examine the sole shape that the robot can walk with stability in rough way.In addition, we change it to the suitable which is in the sole shape and verify that the robot can walk in a slope and rough way stably. As a result, we consider whether reactive behavior is useful or not in the walk in rough way, and examine what kind of influence on navigation.

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Recently, mobile robots like cleaning robot and security robot have been intensively studied. When suchmobile robots are operated, it is necessary to generate their trajectory automatically. In recent years, real-time generation of a dynamic obstacle avoidance trajectory becomes possible by advance of computer. In this paper, a system which automatically generates the target trajectory avoiding obstacles in the indoor environment by real-time optimization is developed. The experiment using omnidirectional vehicle veries the utility of this system.

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This study is concerned with the establishment of the autonomous mobile robot system which includes obstacle recognition and path planning. Ultra sonic sensor is used to recognize obstacles on the moving direction. Proposed path planning method is used the Srinivas's method based on the geometrical, and moving path to the destination is derived by means of the information of moving direction and obstacle position. Finally, the validity of the proposed method is confirmed by simulation and experimental result.

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[in Japanese]

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A working six-legged robot which can switch three modes for locomotion and manipulation was developed. In order to enhance the mobility of this robot, the present study analyzes its performance of climbing up onto steps using dynamic simulator ODE. First tripod gait on horizontal plane is applied to step climbing. The climbable step height by normal walking is analyzed. Second a gait for this robot of climbing up onto higher step with keeping its body horizontal is proposed.

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Phase contrast CT tomographically delineates biological soft tissues, which cannot be clearly imaged using absorption contrast CT, at a high contrast and a high spatial resolution. Since the phase contrast CT extracts phase-shift information by the sample using the x-ray interferometer, a phase unwrapping is required to generate the projections for CT reconstruction from the wrapped phase map. In this research, we propose a novel phase unwrapping method as follows: The wrapped phase map is unwrapped based on AR model, which is used to first detect the site of phase jump in the phase map, and then to correct the phase jump by adding 2np so that the phase map is represented best with the AR model. We investigated the efficacy of the algorithm by simulation data based on actual data acquired at KEK.

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Axial lateral parallel optical interferometry obtains a X-Z interference image using diffracted light as the reference beam and a linear illumination beam without any scan. By scanning a sample mechanically, 300 interference images were measured using an InGaAs camera (320x256 pixels, 60 frames/s, 1.05-ms exposure). 3D shape of a sample was obtained by performing the subtraction of the DC image, which was an averaged interference image, from each interference image, a high-pass filter for the axial direction and the Hilbert transform.

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[in Japanese]

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[in Japanese]

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Teleoperation of space robots is needed to perform tasks such as construction in space. However, time delay is present in these applications. We try to solve this problem by predicting the robot's state in the future. This paper reports the development of an operator-assistant system which gives force feedback to realize tasks requiring delicate operation and its evaluation experiment.

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In this paper, we propose the 3ch architecture with environment estimation based force prediction. The theoretical analysis shows the stability, the convergence of position error to zero and the small force tracking error. Experimental results show the effectiveness of the proposed method.

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This paper addresses improved transparency of teleoperation system by using an impedance control based a new proposed force-reflection(FR)algorithm, where an exerted force by the human operator and a reflecting force from the contact environment are transferred over communication lines with time-varying delays. The input-to-output stability (IOS) small gain approach is used to show the overall FR teleoperation system to be input-to-state stable (ISS). Several experimental results show the effectiveness of our proposed algorithm.

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In our previous work, a novel operator interface named ``active window'' has been proposed. The active window displays inclination information of a mobile robot to an operator through 3D orientation of a screen. As a result, the operator can understand the inclination of the robot intuitively. In this paper the active window is implemented into a newly developed mobile telerobot system.

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In this paper, we introduce a high speed control program of Haptic Interface on ARTL2.6.
The original Haptic interface has been developed in Uchiyama Lab., Tohoku University.
ARTLinux2.6 was released from DHRC in AIST on June 2008. ARTLinux2.6 is installed on Debian4.0 those kernel is 2.6.18.
A software library of Haptic Interface has been developed. We confirm a Haptic Interface control time within 0.2 ms on ARTLinux2.6.

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We have been developing a computer-aided-diagnosis system for evalution of myocardial function by combining MRI and SPECT images.In this study , we calculated wall thickness,blood-flow,and blood-flow per unit myocardial volume by extracting cardiac walls from short-axis images,and registrated MRI and SPECT images.The purpose of this study is to improve the estimation accuracy of wall thickness and registration parameters.To achieve this purpose, we used the 3-D curved surface approximation by NURBS model in contours of cardiac wall detected by level set method.We applied this method to 5 normal and 5 apical hypertrophic cardiomyopathy(APH) cases.We then created a bull's-eye map to display wall thickness,blood-flow,and blood-flow per unit myocardial volume. The results obtained by our method got closer to a result of obtaining by doctor's manual operation by using NURBS approximation.Therefore,it in considered that we could obtain could be ascertained that wall thickness and registration parameters calculated with high precision.

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[in Japanese]

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This paper describes the development of an electric wheelchair which can support bedridden patients. We develop a wheelchair equipped with a simple bed and a portable bath device. Also the small size of the portable toilet with a simple cleaning mechanism is set up under the seat of the wheelchair. Furthermore, we develop a vehicle robot equipped with the toilet that can move inside the house, and can perform cleaning tasks.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Model-Driven PID control system, named MD-PID controller is useful for systems with long dead time. In order to apply MD-PID controller, it is very important to identify process dynamics properly. We developed an Identification Tool of Process Dynamics for those applications. The Identification Tool is applicable not only dynamics from manipulated variables to process variables but also dynamics from disturbance to process variables.

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[in Japanese]

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The process control is recognized as one of the important technical fields in the pulp and paper industry. In this field, the following elements have been greatly expected as important themes: the automated plant operations, the improvements of production efficiency, the production cost reductions, the quality improvements on the static operation periods, and so on. This paper exhibits several intelligent production control trials in the pulp and paper mill. The topics consist of the themes from the most upstream of the production scheduling problems on the mill management, through the midstream of the process control problems, to the most downstream of the logistics problems along the flow of the pulp and paper production processes.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Electroencephalogram (EEG) analysis is crucial in diagnosis of sleep disorders, and many methods have been proposed for automatic analysis of sleep EEG. Most of these methods utilize spectrum analyses without consideration of the generating mechanism of the EEG. In this paper, we apply a subspace identification method to the EEG, assuming that the EEG is generated by a linear stochastic process. Furthermore, we introduce a distance between state-space models to classify the EEG. Results of 24-hours EEG analysis show the potential of our approach in sleep stage classification.

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In this talk, we consider one of the issues related to the control of the insulin for the blood glucose level under the situation in which we can obtain is only the clinical data. Since it is difficult to obtain a mathematical model of a glucose-inslin dynamics in such a situation, we discuss the utility and the effectiveness of, what is called, a data-driven approach to the parameter tuning of a controller. Particularly, we focus on the use of FRIT and so on, which enables us to obtain an appropriate parameter with one-shot experimental data, and validate the effectivenss of this method to the above purpose.

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In order to improve systems medicine from viewpoint of biomedical engineering and system control, a mathematical model was developed to simulate the systemic management of patient's physiological functions under brain hypothermia treatment. The model has been used for simulating any conditions changed in respect of clinical maneuvers in brain hypothermia treatment to find optimal strategy for (i) decoupling control of intracra-nial temperature and pressure, (ii) feedforward control of minute ventilation and (iii) feedback control of anes-thetic infusion for hypothermic intracranial decompression. Simulation results show the effectiveness of the in-tegrative model in discussing the systems medicine.

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