The harvesting operation is hard work for farmers. Workers hope for a reduction of the harvesting operation in agriculture. The purpose of this study is the construction of a useful visual recognition system that is required for automation and robotization of harvesting operations. In this research, eggplants and tomatoes are taken up as an example of agricultural objects. First, they are searched in a scene image using a genetic algorithm. Second, a recognition method for agricultural objects using Neural-Networks is proposed. In these Neural-Networks, the change of luminance information has been learned as special feature of agricultural objects, which show the luminosity distribution of objects composed of curved surfaces. Finally, through experimental studies, it is shown that the new technology proposed here is effective in the recognition of agricultural object.

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Although the technique of performing 3-dimensional measurement of circumference environment had been proposed using the optical flow of a certain time obtained by Active Vision, it was difficult to perform reliable environmental recognition because of the error vector contained in optical flow. In consideration of the hysteresis of optical flow until it results current state from the past, the influence of error vector is mitigated and by using the dynamics of a neural circuits, aims at the system of environmental recognition configuration which can detect the move direction and the improvement in reliability of position detection a still object, or a moving object.

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In the Physical Agent System (PAS), the he robot consists of many sub-systems, such as locomotion, camera to use transmit the information of the remote site and laser pointer used for indicating the operators' intention to the remote site. In this paper, we propose and evaluate the system configuration that consists of the distributed sub-system configuration using I^2C-Bus.

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A mobile robot is being developed which is controlled in a method of teleoperation combined with local autonomy; the teleoperation uses IP network. In the context of the development, a platform has been built up for the purpose to examine the possibility to remote operate mechanical systems through IP network; the platform is made of a four-wheeled mobile machine and a camera. This paper gives experimental results of navigation for the mobile machine using only moving pictures from the camera. Control commands and the pictures are transported through IP network.

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This paper describes a prototype of a new in-pipe mobile high-traction mechanism. A fabricated mechanism is structured by three rubber bellows, lots of friction rings and there electromagnetic valves. A mechanism is driven by pneumatic pressure and vacuum pressure. These two pressures are switched by the electromagnetic valve. The pneumatic pressure (0.1 MPa) is used to stretch and the vacuum pressure (-0.08 MPa) is used to shrink the rubber bellows. The friction rings converts the expansion and contraction movement into the advancement drive. Consequently, The in-pipe mobile high-traction mechanism is moves freely in the pipe and mechanism generated the traction force of 80 N.

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This paper describes a fabrication of an in-pipe mobile microrobot movable in the small diameter pipes. The microrobot is inchworm type and structured by three rubber bellows arranged in series. The rubber bellows is 8 mm in outer diameter, 4mm in inner diameter and 52mm long. The microrobot is connected three air-feeding tubes which are 2mm inner diameter and 2000mm long. The small diameter pipe is 21mm in outer diameter, 18mm in inner diameter and 2000mm long. The microrobot can move with a small diameter pipe by the speed of 151mm when moved by pneumatic pressure of 0.03MPa and vacuum pressure of -0.085MPa.

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A new position surveying micromachine structured by a driving microrobot and a position surveying sensor micromachine is fabricated. The driving microrobot is an inching worm type microrobot driven by the pneumatic pressure. Position surveying sensor is done by using of two rotary encoder sensors. The position surveying micromachine could measure the position at the accuracy less than 1.5 degrees in the angle and less than 600mm in the position in a plastic pipe which has curvature of 40 degrees in its center and is 6850mm long and 44mm in inner diameter.

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This paper presents a simple fuzzy control system for a robot to avoid collision with moving obstacles during its moving to a goal. In the system, the judgment of collision danger degree is based on the relationship between real distance from the robot to the moving obstacle and the initial minimum safety spacing, which depends on the velocities and the relative positions of the robot and the obstacle. The velocity and the steering for avoiding the collision are navigated with fuzzy control by only one input function of danger degree. So, the number of membership functions and fuzzy rules are decreased, the calculation time for real-time obstacle avoidance is reduced, and a quick response can be achieved.

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We designed the new method to measure tribological properties of molecularly thin lubricant film used for head disk interface of hard disk drive system. It is highly required to make more detailed investigation into tribological properties of lubes especially for high speed relative movement with nano-scale surface separation that is most similar state of real head disk interface. Using ball-end optical fiber as a probe we investigated how the tribological properties of confined PFPE lubricant depend on the distance of surface separation.

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Lubrication by extremely thin liquid film has become very important in micro machine, magnetic storage device and so on. When the thickness of lubricant film is thinned to several nanometers, the conventional theories of lubrication cannot be used any more. Molecular dynamics simulation was carried out in the present study to investigate the tribological characteristics of extremely thin film. For high load, namely at small separation, slip is observed near the wall, and friction force vibrates periodically. This result shows that periodical vibration of friction force is caused by stick-slip.

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A novel method for identifying the adhesion force and the dynamic elongation of molecularly thin lubricant coated over DLC surface was developed while an SPM tip retracting from contact position. This method successfully utilizes transient response of the SPM cantilever arising after separation. To describe experimental transient response, a new model for separation process was introduced wherein the surface force decreases from an initial value (contact force) to a terminal value (separation force) in proportion to the tip travel accompanying elongation of the lubricant. Calculated vibration waveforms using this model were found to be in good agreement with observed waveforms.

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Using the molecular dynamics method has simulated three-dimensional meniscus formation on surfaces having two-dimensional sinusoidal roughness. Argon molecules were selected both for liquid and gas molecules moving with a constant temperature of 84K, and stationary solid molecules for solid surfaces. It is observed that the radius of curvature of meniscus varies with the solid-liquid interaction, and normal stress of meniscus is propotional to the curvature.

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The dynamic force between curved surface and Plane linked by a liquid meniscus bridge was analysed assuming small vibration of the spacing. The infinite width meniscus and the finite meniscus ring were considered as analytical models. The incompressible Reynolds equation was solved under the Laplace pressure boundary condition and the solution was linearlized by the small vibration assumption. The derivation of the solutions and the differences by the models were discussed. It was found that the pressure and the load carrying capacity in the linearlized analysis had three terms, i.e., squeeze term by the viscosity of liquid, spring term by the dynamic Laplace pressure and static meniscus force term. Comparisons of the variable contact angle model with the variable boundary position model were also discussed.

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This paper describes the effects of ultra-thin liquid lubricant films on air bearing dynamics and flyability of nano-spacing flying head sliders in hard disk drives. In particular, the effects of non-uniform lubricant film distributions on head-disk interface dynamics are studied. The dynamics of slider is monitored using Acoustic Emission (AE) and the interactions between the slider and disk are investigated. Complex slider responses were observed, which were sensitive to lubricant film thickness. In addition, it is found that the periodic lubricant modulations or re-distributions caused by the slider-disk interactions can be observed.

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Deformations of liquid-gas interface with surface tension caused by moving line gas pressure are analyzed by considering i) quasi-static deformation by the moving line pressure and ii) accompanied deformation caused by squeeze pressure. The former is obtained by the use of Green's function and the latter by solving incompressible Reynolds equation and deformation equation. This method can be easily extended to deformations by distributed gas pressures by superposing the deformations by each line gas pressures.

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The response of pad slider, in which there are a leading pad and a trailing pad, due to disk waviness was analyzed by computer simulation. Because pads on the air bearing surface of the slider are able to occur two pressure peaks severally in leading edge and trailing edge on the air bearing surface to make a moment for pitching motion of slider, the slider can follow the disk waviness with a wavelength shorter than the slider length. But, the slider can not follow the disk waviness with the wavelength which is shorter than the length of pad.

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In this paper the cubic interpolated propagation (CIP) method, which is an effective numerical scheme for differential equations including an advection term and the perturbation method, are employed in the dynamic analyses of the ultra-thin gas film lubrication using the molecular gas-film lubrication (MGL) equation. The 2-DOF slider dynamics for the spacing of several tens of nanometers caused by a waving disk are investigated, and it is found that i) the CIP method is effective and ii) the infinite bearing number approximation is useful for the dynamic analysis of ultra thin spacings.

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For examining molecular gas film lubrication (MGL) characteristics in several nanometers, free molecular MGL equation, which employs Poiseuille and Couette flow rate for free molecular flow region, is established considering surface accommodation effects and calculated the characteristics of plane inclined slider with different accommodation coefficients of disk and slider, α_0 and α_1,as parameters. Static characteristics for ultra-thin spacing or in the free molecular region are found to be indifferent to accommodation coefficients of the slider or stationary boundary.

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The purpose of this study was to show there were two information processing systems for the discrimination of foil/sheet thickness. In an experiment stainless foils/sheets with thickness between 20 and 1000μm were used as stimuli. When the stimuli were thinner than 70μm and thicker than 350μm, they were discriminated in thickness. The stimuli between 70 and 350μm, however, were not discriminated. From the results of experiment it was concluded that the subjects used the two systems for the foil/sheet thickness discrimination.

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This report is concerned with the development of unrestraint and unconscious network system for vital sign monitoring. Lon Works based local network system and cellular phone based mobile network system are integrated through Internet for monitoring the health conditions both at home and outside. Furthermore, a new type pulse meter consisted of PVDF film and conducting fabric and urination sensor with strain gauge are developed and investigated.

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This paper describes a unique technique to assess gait stability utilizing a small and light-weight portable instrument. Lyapunov exponent estimation, a method of nonlinear time series analysis, was applied to quantify the dynamic stability of body sway during walking as measured by accelerometry. Fourteen young and twenty elderly subjects participated this study. Lyapunov exponent of the elderly subjects tended to be higher suggesting lower stability as compared to the younger subjects. Moreover, the elderly subjects suffering joint pain or frequent history of fall presented higher value as compared to those having no joint pain. The results suggest that Lyapunov exponent estimation of walking stability is useful to assess locomotive ability.

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Braille points are characters for visually handicapped persons. However, learning Braille points requires great efforts. This paper is a study on the development of a tactile sensor system for reading Braille points. The sensor is a tactile sensor using a PVDF film as the sensory receptor and is slid over the Braille points with a constant space. Furthermore, the signal processing for distinguishing the characters regardless of the rubbing speed is proposed. The obtained results show that the sensor with the proposed signal processing can recognize the characteristics appropriately.

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This paper is a study on the development of an active palpation sensor for detecting prostate cancer and hypertrophy. The receptor of the sensor is a polyvinylidene fluoride (PVDF) film placed on the surface of the rubber sheet. Considering the steady-state contact of the sensor with the prostate, a concave ceramic is introduced between the sensor and the forefinger. The active sensor is connected to the crank via a stainless beam and driven by the motor. The measurement is done on several prostates. The sensor's discrimination shows good agreement with the clinician's diagnosis.

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3-Dimensional Inernal Structure Microscopes (3D-ISM) have been developed by the authors, which were able to observe internal structures of biological samples by cutting cross-sections with rotating knives. A number of different biological samples were successfully observed by this method. However, this method was effective only for soft tissues due to the cutting mechanism with a flat and thin rotating knife. In this report, a new method used in precision metalworking with single crystalline diamond fly-cutting tool on a ultrahigh precision machine tool was used. A mirror-like cross-sections of a biological sample containig hard tissues like bones were obtained and clear images of micro internal structure of hard tissues were observed.

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A small sensor for detecting xenobiotics in soft tissues was developed in the research. The sensor consists of a rubber balloon probe and a CCD camera. Dot patterns are printed on the inside surface of the balloon probe. When the probe is pressed to the sample. The dot patterns will deform corresponding to the hardness distribution of the sample. Xenobiotics in the sample can then be detected through observing the dot pattern deformation by the CCD camera. Experiments of testing the developed probe were carried out. Principle and design of the probe together with the experimental results are presented.

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In this paper, we describe a method to predict occurrence of fall in human subjects, by using portable instruments and simple criteria. According to the body angular displacements and angular velocity as measured in normal stable walking, a region was defined to assess occurrence of fall especially for the forward fall by trip. Further experimental results confirm feasibility of the proposed method to fall prediction.

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This paper is a study on the development of a haptic sensor system for monitoring skin conditions. The base of the sensor is a copper shell, around which a rubber sponge layer, PVDF film, a protective layer of acetate film and gauze are applied in sequence. The sensor is attached to the tip of an elastic cantilevered beam and pressed against an area of skin. It is then slide over the skin to collect surface morphological features. Through the fundamental experiment using the artificial objects, the surface roughness and softness are evaluated visually by using Symmetrized Dot Pattern. The sensor system is then applied to the clinical test. Results show that the sensor output well describes the skin conditions.

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A suspension with IC-chip, what is called "Chip On Suspension (COS)" is most effective technology to increase data transfer rate of hard disk drives (HDDs). One of the most concern of COS is thermal affective of head suspension. This report is primary experimental study to control the temperature and the displacement of COS. The experimental results are follows. Temperature rises of IC-chip and slider displacements are almost proportional to heating power. The effect of airflow influence temperature distributions of COS, the unbalanced temperature distributions cause slider displacements.

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The fluid bearing is used for hard disk drive and laser scaner, but its cost to performance ratio should be further improved. In this paper we analyzed the stability of disk spindle supported by full cylindrical fluid journal bearing. When gyro effect of rotor is large, We proved that a half frequency whirl of vertical spindle caused by fluid bearing becomes stable when gyro effect of rotor is large. We clarified bearing parameter to make the spindle system stable.

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A low-profile, small-diameter HDD motor for mobile application with fluid dynamic bearing had been developed. The thickness between the bottom of the motor and the top of the disk is 1.9mm. Although the radial bearing length is rather short, disk axial vibration can be reduced with optimization of thrust bearing structure. Magnetic noise from motor to head can be reduced with thin shield plate.

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The areal density of hard disk drives (HDD) is expected to reach 1 Tbits/in^2 with very narrow track width heads below 50nm in the near future. Assuming that the allowable tracking error is 10% of the track width, the tracking accuracy should be less than 5nm. Moreover, when we will investigate track profiles and off-track characteristics using a read-write performance tester, the tracking actuator should have capability of positioning at sub-nanometer resolution. Therefore, an actuator consisting of a linear air bearing and a linear VCM(Voice Coil Motor) was designed for precise tracking. The stiffness of the air bearing was strong enough so that the moving coil of a VCM fixed to the air bearing slider arm could form a cantilever system. The linear actuator showed a much higher resonance frequency than a conventional rotary actuator. Due to the high resonance frequency the servo bandwidth became significantly wider. The linear actuator could be stepped at 1nm resolution without overshoots and undershoots and the rise time was less than 0.15msec.

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A slim three-dimensional actuator for compensating disc tilt in optical disc drives has been developed. It improves the read-write characteristics by inclining the objective lens according to the disc tilt in addition to the focus and track-driving directions. It is a lens-centered structure and has the advantage that it reduces the vibration amplitude at the objective lens, and a moving coil structure of the actuator has the advantage that it increases the driving performance. Experiments on driving performance and tilt servo control were performed, and the results show that this new actuator improves mechanical and read-out characteristics.

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Nonstationary optimal regulator (NOR) is one of the effective methods for positioning control of vibration systems. Generally, many positioning mechanisms such as information equipments and robots adopt dual-stage actuator systems (DSASs). However, the control method for DSASs with mechanical flexibility has not been fully addressed. This study utilizes the NOR technique for positioning control of DSASs taking spring and damping elements of controlled objects into account and discusses a proper combination of time-varying weights for this problem. The effectiveness of this method is verified by numerical calculations and experiments.

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In the case when an electro-static micro actuator has enough high mechanical resonance frequency for its goal servo bandwidth, it can be positioned adequately by open-loop control. But, for design limitations, if it have not sufficient stiffness, closed-loop conrol is needed. Additionally, according to driving mechanism, static electric force is changed not only by an applied voltage but also by its own position. In this case, a control system that have real-time position sensor need to be developped. We suggested a position sensing method using its capacitance change, and evaluate the posibility of controller using this method.

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This paper describes a design of an active head slider using a piezoelectric unimorph cantilever for flying height control. Air bearing surface (ABS) that produces low or negative pressure under the head was designed to reduce the aerodynamic reaction force during the head actuation. The voltage required to lower the head considering the aerodynamic lift force was calculated by the coupling method for fluid-structure interaction. This method enables us to predict the performance of the active head slider in the design process.

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The current design of magnetic disk head sliders needs an extra margin of flying height for manufacturing tolerance or environmental variation. To reduce this margin, we have developed active head sliders. These sliders carry an unimorph piezoelectric micro-actuator and their flying height can be controlled. After simulating the piezoelectric deflection and flying characteristics, we designed two types of active head sliders and fabricated them by silicon micro electro-mechanical systems (MEMS) processing. We solved some fabrication problems left in our previous report and optically observed the slider change its flying height as an electric voltage was applied to the micro-actuator.

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The purpose of this research is to develop the more compact human blood sampling device applied for a now health monitoring system. The mechanical design elements of the device are bio-compatible micro needles, indentation unit using a shape memory alloy (SMS) actuator and pumping unit using a piezoelectric micro actuator. The design concept is the biomimetic micro machine of female mosquito's blood sampling mechanism and the performance of the main mechanical elements are tested. Indentation force of the micro-needle, actual stroke of the indentation unit using a SMA actuator and liquid sampling ability of the pumping unit using a piezoelectric micro-actuator were measured.

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Three-dimensional microstructures can be manufactured by Five-axis micromachining system based on laser ablation. It is possible to move the work above three linear axes and around two rotational axes in this system. Laser is Q-switch Nd-YAG and wavelength is 266nm. Laser and Five-axis micromachning system are controlled by personal computer. A windmill and a bearing were manufactured in this study. Material of the work is polyimide resin. The revolution speed of the windmill was measured.

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To develop a microhand with a force sensor enables to nano-newton-order force sensing to grab and release objects, the microhand composed of a finger driving displacement-enlargement mechanism part driven by a piezoelectric actuator and a finger part made by a piezoelectric film with a force senser was proposed. In the present paper, the displacement characteristics of the displacement-enlargement mechanism with flexural hinges are discussed. Changing the object's dimension, that is, the glass ball diameters 50μm and 100μm, the speeds and methods between the fingers and objects, to grab and release objects, are discussed in the experiments. Next, the manufacturing process of the film finger by use of the semiconducter micromachining technology is shown, and a trial manufacturing of the film is carried out. The manufactured film electric characteristic is investigated experimentally.

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The automatic electric power generator that utilized self-excited rotation has been investigated in order to supply the information devices with electric power. First, the theoretical analysis was carried out in order to obtain the design parameters under constraints such as the setting space and the source of vibration. As a result, it was clarified that for the optimum design of the device there existed a certain relation among the mass and the capacity and the length. Next, an experiment was performed to penerate electricity by using the device. The experimental results agreed well qualitatively with those from the numerical computational analysis.

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For miniaturization of planar inductors with ferrite layers, we have to solve the problem of reduction in inductance. This report shows the effect of turn numbers and upper ferrite thickness. 3.8×3.8mm inductor achieved inductance of 1.3μH and quality factor of 40 at 5MHz. These values are equivalent to those of 6.0×6.0mm inductor shown in previous report^<1)>. On the other hand, because of the small volume of ferrite, the maximum DC bias current of 3.8×3.8mm inductor is smaller than that 6.0×6.0mm inductor.

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We designed and fabricated cylindrical magnetic ac markers for magnetic motion capture system. The ac marker is 12mm long and 7mm in diameter. The oscillation circuit, the magnetic field generating coil and battery have been arranged on the same substrate, and the marker further considered as the battery drive was made as an experiment. A magnetic field of 3.75×10^<-7> Oe was measured using a high-frequency carrier type thin-film magnetic field sensor combined with a carrier-suppressing circuit. The distance detected between sensors and marker was 303mm.

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Rendezvous docking technology is necessary to realize on-orbit service, such as orbit transfer, re-fuel, re-supply of consumable, exchange of equipment, on-orbit construction, etc. Engineering Test Satellite-VII (ETS-VII) performed autonomous rendezvous docking to a cooperative target. Also, it is important to develop rendezvous docking technology to non-cooperative target, which will make hasten on-orbit service. This paper describes on-orbit service missions, and rendezvous docking technologies to cooperative and to non-cooperative targets.

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This paper reviews some concepts of Solar Power Satellite Systems (SSPS) and compares their system configurations, characteristics, construction methods, etc. Organizing subjects on the research and development may clarify the future desirable SSPS.

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This paper describes preliminary study on contact dynamics and its control for capturing non-cooperative satellite. Key-technologies of contact dynamics and goal of control capturing are investigated.

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The key design purposes of the network-distributed controller is to reduce the number of cables through the system, make use of the distributed processors under network environment to compensate fault processing and also enhance the system performance, and to reduce cost ant time by module developments of its software and hardware. These are supposed to be carried out together especially in space applications. With the explanation of its implementation in Reconfigurable Brachiating space Robot, this paper discusses and clarifies the main concepts.

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A stereo vision system for estimating the relative attitude, position and motion of large objects in orbit is being developed for use in a debris removal system that would perform operations such as observation, investigation, capture, repair, refuel and de-orbit of satellites and large space debris. An on-orbit visual environment simulator has been prepared to simulate the on-orbit visual environment for terrestrial experiments. Preliminary investigations using this simulator have examined the performance of a stereo vision system in extracting the three-dimensional shape of a miniature satellite model.

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It is expected that autonomous space robots conduct many on-orbit servicings, for example the construction and maintenance of large space structures as well as the capture and recovery of damaged satellites. In order to realize these missions, robot manipulators mounted on a satellite can be useful. During the capturing operation of a floating target, it may be difficult for a manipulator to grapple it directly because of target nutation or tumbling. In order to damp the angular momentum of target, the method using a cushion type damper has been proposed. After grappling the target, it is necessary to handle the payload suppressing the vibration. We will analyze the handling operation of the flexible payload by dual manipulator. In this paper, we report the results of the ground experiment and the numerical simulation, and discuss the validity and feasibility of this operation.

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This paper suggests posture control technique of manipulator-like variable geometry truss (VGT) structures by distributed control rule. In the control problem of VGT posture and position at the tip, it is inefficient and difficult to decide control values of large scale control problem by central control. Therefore the distributed control technique is adopted for this problem. The distributed control problem of VGT is decomposed into a set of optimization sub-problems which consist of a objective function of control energy and tip positioning geometrical constraints of VGT tip. Each control value of length adjustable members is determined by solving each optimization sub-problem independently and separately. The validity of suggested technique is confirmed by the experiment.

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