This paper describes a simple method for skating by small biped robot. Humanoid (biped) robots are generally slower speed and more energy than other robots during locomotion. Skating is one of the way solves their problems. We proposed a skating method by a biped robot which uses swaying motion. A biped Robot given angular velocity about roll axis gets propulsive force of skating when impulsive force arise between its support leg and the ground. We developed a small skating robot with 2DOF ankle joint a leg. With the robot, we achieved straight skating and turning skating. However, the robot has hardware problems. So, we developed a new model robot.

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Small humanoid robots can enter the narrow space, so there is hope that they work for lifesaving at the time of disaster or house-sitting in the home. In order to work enough in such spaces, the robot must move freely over obstacles like stairs or heaps of rubble. In this research, as the robot can move freely we propose to develop the remote operation system. Kinect that is a high-performance camera is mounted to the robot, and the operator recognizes the surrounding environment though Kinect. And operator can control the robot, the operation is reflected to the experimental robot. As the first step, we started recognition of surrounding environment and the body movement with Kinect.

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In this study, the trajectory of a mobile robot is controlled by using a method based on the time state control form. The convergence speed and the trajectories of the robot with different control parameters were investigated in experiments. The experimental results agreed well with the theoretical results. Therefore, it is possible to adjust the control parameters of this robot based on linear control theory. The distance to obstacles was measured by using a laser range finder. The robot avoided the obstacles and reached the target position, traveling back and forth automatically. When the obstacles was close to the target position, the number of times of switching the traveling direction increased and the time required for reaching the target position became long.

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A method for object detection based on impacting is proposed here. In this method, a robot changes object positions by impacting. And then the robot can detect each of the objects individually from camera images before and after impacting. This detection is possible because feature points of each object always move consistently by impacting, while those of the background do not move. The proposed method was implemented and validated by picking experiments of various objects.

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This paper proposes a novel approach to synthesize a human grasp posture using a database that stores contact region information. A posture to grasp a new object can be generated by interpolation with optimization-based adjustment using the proposed database, given a goal contact state of the hand with the object. In this database, a hand posture is defined by joints angles, and therefore this proposed method is applicable to variously-sized hands. Generated grasp postures for each of various hands can be evaluated visually, which can aid in a product design.

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This paper describes the transport of a liquid container by a robot, due to the demand for the conveyance of molten metal in casting processes, for the tray service by robots, and so on. Since liquid in a container can wave greatly by changes of transport velocity due to the inertial force acting on its own, robots are not able to carry the container as a rigid box. Therefore, the transportation of one or more liquid containers using a robot requires a carrying method which prevents content fluid from being spilled from the container. The proposed method, the TGCW (Trajectory Generation to Control Wave) method, is a feed-forward control to realize the prevention of the spillover of content fluid. To reveal the performance of the TGCW method, we perform the verification by simulation using the explicit MPS (Moving Particle Simulation) method and by experiment.

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The cell production method, which facilitates high-product-mix and low-volume manufacturing, has been expanding into the mainstream, and demand has been growing for a robot similar in size to workers that can dexterously act as a multiskilled worker and handle heavy materials hi a cell production line. We have developed a hydraulic double-arm robot that is equipped with hydraulic actuators for the arms, allowing it to handle heavy materials, and the TV800 vertical articulated robot arm consisting of electric actuators produced by Toshiba Machine Co., Ltd. For the wrists, allowing it to also achieve dexterous handling operations. Also, we have developed a new fault detection system equipped with this robot. This system can detect faults of materials, not only by visual inspection, but also by weight inspection. In this paper, we discussed the performance evaluation of this system.

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AC Magnetic suspension system using magnetic resonant coupling has been proposed which has the performance of noncontact energy transfer to the suspended object (floator). This system has the self-stabilization property so that passive suspension is possible. In this paper, an experimental apparatus is fabricated which has three pairs of primary and secondary electromagnets for three-axis suspension; three primary electromagnets are fixed to the stator, and three secondary electromagnets are fixed to the floator. The floator is successfully suspended without any mechanical contact. Stable suspension is achieved by supporting the stator through springs and dampers.

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We study a new robot programming method that uses the view-based approach: "view-based teaching/playback." This method directly uses view of images and can accommodate itself to changes of task conditions. However, the view-based teaching/playback was not applicable to force-control tasks because this method cannot deal with tasks like pressing objects against walls, in which view of images does not change. In this paper, We applied the view-based teaching/playback to force-control tasks in order to expand the range of application of this method. By mounting a flexible material on the robot hand or utilizing the photoelastic method, view-based teaching/playback succeeded in wall-pressing tasks.

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Safety is one of the most important issues in rehabilitation robot suits. We have designed a rehabilitation robot suit equipped with two mechanical safety devices called the "Velocity-based safety device" and the "torque-based safety device". The robot suit assists a patient's knee joint. The safety devices consist of only passive mechanical components without actuators, controllers, or batteries. The torque-based safety device stops the robot suit if it detects an unexpected high joint torque. Similarly, the velocity-based safety device stops the robot suit if it detects an unexpected high joint angular velocity. The mechanism for detecting the unexpected angular velocity in the velocity-based safety device is a mass-spring-damper system. In this paper, we firstly review the rehabilitation robot suit equipped with the safety devices. Secondly, we design and develop the mechanism for detecting the unexpected angular velocity by considering the natural frequency. Finally, we present experimental results to verify the effectiveness of the velocity-based safety device with the developed mechanism.

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This paper deals with a control method of a position of a robot manipulator and a contact force. The proposed control method considers a virtual impedance repairing the error between the reference signal and the control value. The proposed control method is compared with the conventional control method in the simulations and the experiments. The state equation of the control object was derived, and the simulations were done. As a result, the robot arm follows the target values of the position and the force. We confirmed the effectiveness of the proposed control method considering the virtual impedance.

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Recently, adhesive bonding has been used in functional composite structures. The purpose of this study was to clarify the strength properties for adhesively bonded single-lap joints composed of unidirectional CFRP and metal material adherends subjected to tensile shear loads. Tensile shear experiments using universal test machine were carried out to measure the failure loads of various joints. In addition, the effects of adhesive thickness, lap length and metal side adherend on the tensile shear strength were investigated. From the experimental results, it was found that the tensile shear strength and crosshead displacement increase as Young's modulus of the metal adherend increase. Furthermore, the tensile shear strength became reduced with increasing the lap length. Besides, no regularity was recognized between the adhesive thickness and the tensile shear strength.

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In this study, we have newly proposed some joint configurations to improvement of tensile shear strength of the adhesively single-lap joint, and we named that "Five holes crosswise arranged joint". Mechanical property in the presented joint subjected to static tensile load was analyzed, using Finite Element Method. FEM analyses were carried out to clarify the stress distribution at the bonded part. To evaluation the tensile shear strengths of various joints, tensile experiments were performed by universal test machine. As a numerical result, it was found that stress concentrations occur at near the adherend holed parts in adhesive layer. From the tensile experiments, it was also proved that the fracture load of five holes crosswise arranged joint becomes increase than conventional joint.

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In this study, we aim to clarify the strength properties when the tensile shear loads were applied to the adhesively wavy-lap joints with dissimilar adherends. To evaluate the strength properties for each joint, experiments to measure the fracture loads of the joints were carried out by using a precious universal testing machine. As a result, it was found that the tensile shear strength and the maximum displacement increase case where the material of other adherend in the dissimilar joints is used mild steel SS400. It was also proved that compared with the similar adherends in previous study, the tensile shear strengths in the case of dissimilar adherends decrease. In addition, it was seen that the interface failure between an adhesive layer and the adherend become occupy at bounded part in all of joints.

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A purpose of this laboratory is to investigate influence to give the better processing method in the model bending test of aluminum honeycomb materials for a processing result by sounding out lapis lazuli, the change of the dynamic moment. I performed bending to aluminum honeycomb materials while changing a dynamic processing condition and groped for a method to machine in an objective shape. The result of this study is connected directly with possibility of the expansion of the use of lightweight high-stiffness honeycomb materials. I investigated a method to predict the observation of the spring back phenomenon and spring back quantity when I made bending on an aluminum alloy honeycomb structure body this year.

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When we estimate the fatigue life, we have to conduct FE analysis using a constitutive model which can exhibit the mechanical properties of lead-free solder alloy. As such mechanical properties of lead-free solder joints under cyclic thermal loading, the stress strain curves, stress strain hysteresis loops and stress relaxation curves with these temperature dependencies and these rate dependencies are regarded. In addition, these solder joints under cyclic temperature load are stressed mainly in shear and the solder alloys have scale effect. Thus in this study, for FE analysis of solder joints under cyclic temperature load, we carried out tensile tests, tension-compressive tests and the stress-relaxation tests of lead-free solder alloy using the small sized shear specimen.

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Classical elastic-plastic-creep model and ANAND model are often used because these models are implemented into commercial FEA soft. However, in ANAND model and classical decoupled creep and plasticity model, how accuracy simulation results by each model accord with experimental test data have been not clarified and how the agreement degree to mechanical properties had influences on life time fatigue have been not enough investigated. So, in this study, at first, for the purpose of getting basic data to investigate these influences, we investigated how accuracy simulation results by each model accord with these experimental test data. Next, using these models, we conduct FE structural analysis of solder joints onactual equipment. This paper will report the progress of this study.

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In this study, so-called topology optimization techniques were numerically applied to structural optimization problems of the core layers in sandwich composite beams with facing skin layers of carbon-fiber reinforced plastics (CFRP) under several static flexural loads such as central concentrated load, uniformly distributed load and their combinations. General-purpose finite element analysis code, MSC Nastran, and its pre-post processor, Patran, were used in the present study, in which the density method, one of the numerical approach, was employed for seeking more light-weight and stiffer core structures by compliance minimization. From the results being obtained at the current moment, certain optimal inner structures or morphologies possibly could be found out for each set of structural and material configurations and various boundary conditions.

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We suppose the disturbances for many circular holes-that are free boundary to an elastic medium (matrix) of infinite extent under in-plane problem. The matrix is subjected to arbitrary loading, for example, by uniform stresses. From past studies, we derive these general solutions for the theory of elasticity. We observe the stress around the holes from this solution and analysis of FEM (ANSYS). We focus on the disturbances of the stress due to the span between the circular holes, the circular holes size and arrangement pattern. In this paper, we analysis disturbances of stress by different arrangement pattern of the circular holes under the circular holes of same number. Several numerical examples are presented graphically. From the graphs, we consider validity of the theoretical solution of the theory of elasticity.

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On polymer materials, investigations of stress-relaxation properties are strongly desired for design of engineering materials. In this study, stress-relaxation property tests of POM and the PTFE polymer materials were examined at 25 ℃. Next, we analyzed these properties by Norton's law and also proposed compatibility for FE technology. Then, we analyzed the conducted material tests using the proposed technology and compared FE analysis results with experimental test data to examine the validity of the proposed technology. As a result, it was confirmed that analytical results were in good agreements with the experimental ones.

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We introduce a system to reconstruct LEGO models from multiple two-dimensional images of complex objects taken from different views based on shape from silhouettes (SFS) technique. We employ a unit voxel with edge length ratios 5:5:6 for the SFS method, and convert the resulting voxel models with color information to LEGO models. In order to minimize the number of LEGO bricks, we remove interior voxels as much as possible before the conversion so that the thickness of the voxel model is uniform from the surface voxels. We also add supporting bricks to interior as well as exterior of the model to strengthen or ease the difficulty of construction. Complex examples are provided to demonstrate the effectiveness of the proposed algorithms.

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In 3D printing technology, fused deposition modeling (FDM) is used with continuous carbon fiber reinforced thermoplastic (CFRTP). In this study, polylactic acid (PLA) was used as the matrix material and continuous carbon fiber was used as the reinforcement material. A method was adopted for in-site fiber impregnation of PLA filaments in a continuous carbon fiber bundle that are separately supplied and then mixed in a heater before ejection. A dumbbell-shaped CFRTP specimen was made using the developed 3D printer for a tensile test. The tensile test results showed that the continuous fiber reinforcement improved the tensile stiffness and strength. However, the tensile properties were slightly less than those expected by the rule of mixtures. Observation of the fracture surface showed insufficient impregnation and some gaps between filaments, which reduced the improvement in the tensile properties of the CFRTP.

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It is enthusiastically movement for use in research and development because three-dimensional printer (3D printer) is very suitable for prototyping. Therefore, material testing and X-ray Computed tomography (X-ray CT) observation is conducted on test specimen and different phase shift of composite materials which is manufactured by using 3D printer. By the X-ray CT, those test specimens consider to fabric composite laminates. As the result, test specimen show that modulus of transverse elasticity is value almost same as database and modulus of longitudinal elasticity is greatly lower than modulus of elasticity by database. And in tension test, the composite materials meet the compound rule, and the modulus of elasticity varies depending on the condition of phase shift, hi torsion test, the composite materials do not meet the compound rule.

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We have developed a novel micro stereolithography that can provide scalable resolutions by using multiple optical fibers. Three kinds of optical fibers with different core diameter were used in experiments. First, we used the optical fiber (mode field diameter: 2.4 μm). In this case, the highest resolution of about 1 μm has been achieved. The use of optical fibers whose core diameters of 50 and 200μm allows us to obtain the resolution ranging from 10 to 150 μm. From these results, we have verified that the micro stereolithography using multiple optical fibers can adjust the resolution by changing the optical fibers. Additionally, we have succeeded in fabricating not only two-dimensional (2-D) patterns but also three-dimensional (3-D) structures. As an example of 3-D structures, a pyramidal structure was successfully fabricated.

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In this study, we propose a novel method to fabricate three-dimensional (3D) magnetic microparts by the combination of two-photon microfabrication and electroless plating. In this method, polymeric microparts made by two-photon microfabrication were magnetized by electroless plating. In experiments, magnetic microparts could be successfully fabricated by modifying various experimental conditions of electroless plating. In addition, energy dispersive X-ray spectrometry (EDS) clarifies that iron oxide nanoparticles were deposited onto the polymeric microstructure site-selectively. We also fabricated magnetic microrotors, and then they were successfully driven with a simple ferromagnet. Since such magnetic microparts can be remotely driven, our fabrication process will be applied to not only functional lab-on-a-chip devices but also biological manipulation tools.

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This paper deals with a study on a vibration control system using propellers for crane load. Vibration suppression of crane load suspended by hoisting rope is an important issue to speed-up crane operation. In this study, a novel vibration control system using propeller thrust as control forces is presented. The pitch of the propeller can be varied so that the attack angle of the propeller blade possess negative or positive. The normal propeller must switch on or off of the device repeatedly, so that rising properties of the force of propeller is bad. Variable-pitch propeller solved this problem. Changing the attack angle, the direction of thrust can be altered smoothly. The fundamental property of the system is already confirmed and practical system has been developed. The performance of the system is experimentally examined in this report.

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At disaster scenes, an injured person on a stretcher and loads are carried by a helicopter. They are suspended from the craft's body. This method is useful, but disturbance such as wind will induce rotation of the loads. To avoid this, equipping CMGs (Control Moment Gyro) will be effective to cancel disturbances. Recently, CMG with a single wheel is used at a construction site. This paper considers an application of scissors CMGs and simulates the above situation. In this paper, we propose a new scheme considering unload of the angular momentum by means of torsion torque of the tether, then simulates yawing motion in the wide disturbance range to verify the utility of the proposed scheme.

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In a factory, the continuous thin steel plates are subjected to iron and steel processes are supported by a series of rollers during processes such as plating and rolling. However, because the rollers come in contact with the steel plates, the problem of surface quality deterioration arises. To solve this problem, we developed a non-contact guide system for parts of the steel plate at which its traveling direction changes in high-speed traveling by applying an electromagnetic force from the direction of the edge of the thin steel plate, and experimentally examined the effectiveness of the system. However, the asymmetry traveling steel plate during uncontrolled is not calculated theoretically. In this study, the shape of traveling steel plate is calculated with numerical analysis. And we checked the validity of this proposal by experiment.

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Various robots have been researching for many years. Because of the Square-cube law, we are not able to build gigantic robot with ordinary robot structure. We found that Tensegric structure is suitable for building a robot over 10m height. In Tensegrity, form is achieved by using a set of disconnected rigid elements connected by continuous network of tensile elements. Tensegrity structure is so light that the king size structure can be constructed neglecting the square-cube law. Assume the starting state of the Tensegric structure arm is standing straight. The arm moves from the starting state, and expected to reach the ending point smoothly. This paper discuss an idea of optimal trajectory for the multistage Tensegric structure arm.

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The recent automobile industry has prevailed on ultra-compact electric vehicle, andademandfornoise reduction control inside the vehicle. In consideration of the requirement for quietness improvement and reduction of weight, an active noise control (ANC) system has been attracting much attention. This method is effective for noise with low frequency. In this study, we propose an ANC system by using the vibration of giant magnetostrictive actuator and we aim to reduce the noise level in an interior of a vehicle using this proposed ANC system. The giant magnetostrictive actuator has a high output that is sufficiently controllable inside a vehicle space and at the same time has high space efficiency. In this paper, the giant magnetostrictive actuator is installed at windshield of the enclosure that acts as a vehicle, and the noise reduction effect to ANC were examined as the noise applied to the box from outside.

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This paper proposes a new type of active seismometer measuring vibration possessing long period and wide dynamic range. In order to lower the natural frequency and expand the detectable amplitude, the sensor with the low natural frequency is realized by using feedback control. Moreover, to compensate phase-delay, third order phase-lag compensator is added to shape measured output. It has been demonstrated that the detectable frequency range of the sensor is extended from 0.1 [Hz] to 10[Hz], while the dynamic range of that is expanded up to 57[dB], namely vibrations that possess 700times larger amplitude than the maximum stroke of the sensor. New sensor body is produced and tested.

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Aluminum-alloy-cantilever hammering tests were carried out using fiber Bragg grating (FBG) sensors, piezo-electric accelerometers and strain-gages to evaluate measumental easiness of the fixed end vibrations. Although accelerometers are uesd in vibration tests genenally, it is diffult to mesure the fixed end vibrations of cantileverers because of short arm lengths. However, it is expected that adopting FBG sesnors makes measuring dyanamic strains at the fixed end easy.The tests results show that FBG sensors can measure wider freqeucy-range vibrations than those in the cases using accelerometers. Moreover, it was easy to comapare the frequency analysis results of FBG sesnosr signals and the FEM analysis results. These results show that it is effective to measure vibrations at the fixed ends of cantilevers using FBG sensors.

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The purpose of this study is to develop an amplifier free accelerometer using a laminated PZT element of power generation element of high output among the piezo element. The evaluation of output characteristics of the voltage sensitivity, frequency characteristic and the phase difference with respect to vibration acceleration input of the laminated piezoelectric element weight is attached to the tip to improve the voltage output characteristic. The effects of measurement impedance in measuring circuit to the laminated PZT sensor on output characteristics of voltage sensitivity, frequency characteristics and phase difference of the laminated piezoelectric element are evaluated by vibration power generation tests.

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For improving vehicle control and safety, intelligent tires which is equipped with sensors and monitoring tire/road contact condition is demanded. To identify the coefficient of friction of tire/road surfaces during driving including cornering, we constructed an identification scheme of the coefficient of friction through estimating the slip angle and applied force by attaching single lightweight triaxial acceleration meter on the inner tire surface. To validate the proposed scheme, we conducted tire-rolling tests using accelerometer-equipped tire with various slip angles on various types of road surfaces including dry and wet conditions. As a result, it was confirmed that the estimated slip angle and applied force are reasonable, and the coefficient of friction is identified with high accuracy compared with that measured by standardized tests of the coefficient of friction.

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The comparison of sensor type; microphone, acceleration pick up and strain sensor are dealt with for rotating machine in terms of frequency range for structural health monitoring purpose, hi case of ambient vibration, the response sensitivity is utilized to identify the defective location.

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Recently, demand in improving of quality for thin steel plates used in various industrial products is increasing. We have proposed a magnetic levitation control system and confirmed its realization by means of a digital control experiment. However, the use of a limited number of electromagnets cannot suppress static deflection and high-order-mode elastic vibration, which are characteristics of a flexible magnetic material. To solve this problem, we have proposed a hybrid levitation control system for thin steel plate using the magnetic force generated by permanent magnets, which have no operational costs. In this study, we attempt to determine the optimal placement and number of permanent magnets to reduce the deflection of a thin steel plate under considering interacted magnetic field of permanent magnets.

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The purpose of this study is to develop a three-dimensional passive dynamic damper using springs with high damping material to reduce multiple vibration modes of three-dimensional piping systems. In this paper, first, concepts for design of a three-dimensional passive dynamic damper are described. Further, multiple TMD theory is proposed as the best design method of the three-dimensional passive dynamic damper. Next, vibration tests using a dynamic damper model with high damping springs and a 3D pipe model are performed in order to investigate effects of vibration reductions of the dynamic damper model. In sine wave excitation tests, the resonance responses of 3D pipe model are reduced by using the dynamic damper model. In seismic wave excitation tests, the seismic responses in multiple modes of the 3D pipe model are reduced by the using dynamic damper model. As a result, the seismic response s of the 3D pipe model are confirmed to be greatly improved by using the dynamic damper model.

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The purpose of this study is to develop methods to improve damping characteristics using a high damping material for reducing earthquake responses of equipments and piping system of nuclear plant, hi this paper, a structure attaching the Mn-Cu alloy as a high damping material to improve the damping characteristics of the piping structure is proposed. Vibration tests using 3D steel pipe attached with Mn-Cu alloy are performed. Further, Damping characteristics of the piping structure are evaluated by frequency response analyses using the finite element method. From these experimental and analytical results, the validity of the damping characteristic evaluation method and the method for improvement of damping characteristics of the 3D steel pipe using Mn-Cu alloy are confirmed.

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General damping systems, such as a viscoelastic damper, a friction damper, a dynamic vibration absorber are developed. However, those systems have several faults such as temperature dependence of viscous fluid, frictional wear, and decrease of damping effectiveness by parameter change of the main vibration system. We propose eddy current damper which uses permanent magnets in consideration of these faults. In this paper, the effectiveness of the damper is confirmed by the results of acceleration Fourier spectrum ratio in the excitation test and the simulation. These two experimental results are clarified by a one-story house model and the single degree-of-freedom system of the model, hi the excitation test, acceleration Fourier spectrum ratio of the equipment is greatly reduced by installing the damper. And also, damping ratio increases to about 20 times compared to the case without the damper. In the simulation, the decrease of absolute acceleration response is confirmed.

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In recent years, a large scale of earthquake occurs all over the world. Hence, controlling seismic response of houses is important for protection from destructive earthquakes. In this paper, we proposed a small Silicon Oil damper for vibration control device for housing. The effectiveness of the damper is examined by careful experiment, and the validity was confirmed by simulation. The result verified that there was a damping effect in every condition. Especially, sphere damper with 50000 [cSt] silicon oil has the most damping effect.

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An Energy-Regenerative MR damper was constructed and its performance was studied experimentally. Magneto-rheological (MR) Grease is known as a smart material witch can change its Theological property by magnetic field. MR damper is a kind of oil damper which uses MR Grease as working oil. Usually, this type of damper has an electric coil, and applying current to it, magnetic circuit is formed and the damping property of MR damper can be changed. This time, an energy regenerating mechanism which is composed of a ball screw system and a generator was attached to MR damper. By vibration experiment, the damping force and regenerated current were measured. This experiment revealed that up to 30% of energy was regenerated.

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In order to familiarize an isolation system for museum arts, a simple small isolation system was developed. In this study, characteristics of this system and variation of response were analyzed by a SDOF model. Input waves were used as seismic ground motion, and a friction coefficient on this system was assumed as 0.10. In all cases, the peak acceleration response amplitudes were decreased compared to peak acceleration amplitude on input waves. However the decrease rate of RMS depended on the waveform character. From seismic intensity scale point of view, it was decreased in the intensity scale 0.63 with standard deviation ± 0.48. Since a relation between peak response acceleration and peak relative displacement indicates trade-off on this system, it is important for a design of this system to decide the friction coefficient carefully.

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In order to explain spectral ratios of response/input on a small base isolation system using friction bearings, some numerical simulations were investigated using 1DOF or 2DOF models. The shape of spectral ratio in case using only marble plate type bearings indicates flat until the frequency of 4.0Hz. However it seems to be flat, since the spectral peak at the frequency of 3.5Hz grew up. The spectral ratio in case using ball type and marble type bearings indicates flat until the frequency of 0.4 Hz and decays with a slop of f-1. Comparing between the spectral ratios and the transfer functions using 1DOF model, they seem to good agreements. However it is difficult to explain the small spectral peak at the frequency of 3.5 Hz, especially in case using only marble plate type bearings. And it is also impossible to explain the transfer function using 2DOF model.

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In this paper, a novel combination of structures for connected-control mechanism (CCM) is presented. By coupling base-isolation and ordinary structures, the vibration suppression effect of CCM is expected to be expanded, while the stroke of base-isolation layer is hopefully suppressed. Experimental structures and CCM mechanism using magnetic dampers are built and excitation experiments are carried out. The effects of the numbers and locations of the dampers are examined. In this experiment springs that are designed according to fixed point theory are used to obtain the vibration suppression effect.

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This paper presents a novel modeling method and a control system design procedure for a flexible rotor with many elastic modes using active magnetic bearings. Stable levitation of the rotor is achieved by using simplified flexible rotor-Active Magnetic Bearings system model, a designed local jerk feedback control system, and a phase-lag compensator. But the 2nd mode was not enough suppressed. In order to suppress the 2nd mode, change of the shape of the rotor and verification of its effectiveness are carried out. The target of our research is to let the rotor rotate passing over the 1st and the 2nd critical speeds caused by flexible modes.

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Thin steel plates are widely used in various industrial products. But there are problems where deterioration of surface quality and metal plating occurred by transporting. As a solution to these problems, a noncontact transport of steel plate using electromagnetic force has been proposed. However, there is a risk that side slipping or the dropping of the plate may occur owing to inertial force because the levitation control system does not provide a restraining for the direction of travel. Therefore we have proposed the addition of electromagnetic actuators to control the horizontal motion of levitated steel plate, hi this report, we examine the relationship of the levitation probability and deflection with the addition of positioning control in its horizontal direction. It was confirmed that the magnetic field from the horizontal direction was effective for stabilizing the levitation of the thin steel plate.

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In the conveyance manufacturing process of thin steel plate, the quality of the plate surface deteriorates because the plate is usually in contact with the rollers. To solve this problem, electromagnetic levitation technologies have been studied. However, when an ultrathin and flexible steel plate is to be levitated, levitation control becomes difficult because the ultrathin steel plate undergoes increased flexure. We have proposed the levitation of an ultrathin steel plate that is bent to an extent which does not induce plastic deformation. In this study to elucidate the levitation stability under disturbance, random disturbance was input into the levitation system and bending levitation experiments were carried out using the ultrathin steel plate with a thickness of 0.18 mm.

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A thin-wall metal bellows device which is air-tight, capable of handling large expansion and pressure-resistant is developed for pneumatic use. By installing viscoelastic rings in the folds of the bellows, a bending stress caused by the inner air pressure is relaxed, and the pressure-resistance performance of the bellows is improved. During the usage of the bellows as an air spring, surging phenomenon can cause high stresses, and the bellows can break, hi this study, the elastic characteristics of the pressure-resistant metal bellows are measured in order to consider the vibration attenuation caused by the viscoelastic rings.

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A rotational/linear two degrees-of-freedom switched reluctance motor (2DOF-SRM) has been developed for the purpose of independent control of rotational and linear actuations on one actuator. The prototype 2DOF-SRM has 3 photo switches on the stator, detecting the rotor angular position for excitation of phase windings for rotational speed control. And an exterior linear position sensor was attached to the outside of the motor to detect the rotor axial position for linear displacement control. To improve sensing resolution and simplify the sensing system, this research developed the built-in high resolution angular and axial position sensor in which the rotor is used as the sensor target. This paper presents the sensing principle of the developed sensor and its performance.

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In a conventional axial flow turbo pump, the electric motor is equipped to the pump apart from the impeller, and is coupled to the impeller by the drive shaft passing through the pump casing. To prevent the leakage at the clearance between the shaft and casing, a seal device is indispensable. Furthermore, the curved conduit due to the in-line layout from the impeller to the motor increases flow resistance, and makes plumbing complicated. Aiming to straighten the conduit and to remove the necessity to maintain the seal, this paper presents a novel axial flow turbo pump structure with switched reluctance drive system. In this pump, the impeller acts itself as motor rotor, and is driven directly by the electromagnetic torque based on the principle of switched reluctance drive. This paper describes the design approach of the electromagnetic direct drive pump applying combination of fluid machinery design.

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