An ultra compact orbital welding machine for butt welding of water-wall tubes of power generating boilers on erection sites has been developed. The minimum radial clearance of the welding head is 20 mm, and this value is below the half of the existing orbital welding machines. To achieve the 20 mm radial clearance, the new arc length control mechanism and the flat welding torch of 7 mm thickness have been developed. The high quality of welds was achieved by installing arc length control function to adopt new structural differential motion mechanism. To make the flow of the shielding gas a uniform flow, the metal fiber filter was set up at the gas blow exit of the thin torch.Using the developed orbital welding machines, several thousand joints of water-wall tubes of power generating boiler have been successfully welded on erection site.

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In this paper, a high-speed range image sensor using a multi-spot laser projector is constructed. Several high-speed range image sensors have been developed recently. Their sampling rate is around the video rate (30 Hz or so) and a faster sensor is required such as the 1 ms vision developed by Ishikawa for measurement of ordinary images. The proposed sensor has achieved 200 Hz measurement. It consists of a commercially available laser projector and a high-speed CCD camera. The distance to each projected spot is measured by triangulation. To achieve fast measurement, each spot image is searched in one line (epipolar line). The laser projector is rotated by 14 deg. and consequently, the number of pixels assigned to each spot is magnified by more than 4 times. The number of pixels of the constructed sensor is 361 and its measurement range is 800-2000 mm. Although the acquired range image is sparse, the proposed sensor is thought to be adequate for several applications such as robot vision because of its high-speed imaging and compactness. Some characteristics such as measurement errors are discussed, and the effectiveness of the proposed sensor is verified by experiments.

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This paper describes static loading tests results of earthquake isolation system using vertically utilized coiled springs and discusses analytical model for elastic coiled springs. The static loading tests were carried out for two types of elastic coiled spring in which had a different material SUP 9 and SUS 304 stainless steel. The elastic coiled springs were designed to provide a 10 000 kg rated mass with a horizontal natural frequency about 0.20 Hz and that they could accept a displacement of about 200 mm or more. Fundamental characteristics of the elastic coiled springs such as transverse stiffness of coiled spring and the effects of the restoring force characteristics by the difference between the pressurization directions were clarified through the static tests. These characteristics of transverse stiffness of elastic coiled spring were analyzed using simple model good results were obtained.

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This paper describes static loading tests results of elasto-plastic coiled springs and discusses analytical model for hysteretic restoring force. The static loading tests were carried out for two types of elasto-plastic coiled spring in which had a different material SS400 and SWRM17 steel. The elasto-plastic coiled springs were designed to provide a 1 000 kg rated mass with a horizontal 1st natural frequency about 0.74 Hz, yield displacement of about 25 mm and an equivalent damping ratio of 30% or more. The tests results revealed various properties of horizontal stiffness and equivalent damping ratios obtained from the hysteretic restoring force loops. The repeated shear deformation tests showed that the coiled springs could keep their integrity thought the 100-cycle repetition tests. An analytical model for elasto-plastic coiled springs was proposed to express the horizontal hysteretic restoring force, and validity of the analytical model was evaluated.

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In this study we make clear the characteristics of an air suspension with a flow channel connected from a cylinder to a reservoir tank. The flow resistance of channel is given by a viscous restriction or an orifice restriction. Differences between approximated analytical results, which are based on the 3-element model, of stiffness and damping coefficients of the air suspension with the viscous restriction and results of numerical analysis considering non-linear characteristics are very small. Moreover, the approximated analytical results of a transfer function of the air suspension and the experimental results of it are good well. Dependence of the oscillating amplitude on the maximum value of the transfer function of the air suspension system with the viscous restriction is very small since dependence of the oscillating amplitude on the stiffness and the damping is almost negligible. However, it depends on the oscillating amplitude of air suspension system with the orifice restriction because the damping coefficient of that decreases when the oscillating amplitude decreases. We can choose the optimal restriction coefficient of viscous restriction to minimize resonance amplitude easily. However, it is difficult to choose the optimal restriction coefficient of orifice restriction to minimize resonance amplitude because the oscillating amplitude often fluctuates generally. Thus, the air suspension with the viscous restriction is better for isolating the small vibration, in case of the high precision machinery.

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In this study we propose a design procedure of an air suspension with a viscous damping restriction and a reservoir tank. We use two design concepts of minimizing resonance amplitude and minimizing standard deviation of amplitude against external disturbance random vibrations of foundation. In order to reducing resonance amplitude and standard deviation of amplitude, it is necessary to increase the volume ratio of the reservoir tank to the main cylinder. In these case, we can choose the optimum damping ratio which corresponds to the restriction coefficient of viscous restriction to minimize resonance amplitude or standard deviation of amplitude. As the volume ratio becomes larger, the difference between the optimum damping ratio which provides minimum resonance amplitude and what provides minimum standard deviation of amplitude becomes larger. However, we can realize the air suspension whose standard deviation of amplitude is relatively small although we choose the volume ratio and the damping ratio to minimize the resonance amplitude.

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The objective of this study is to improve the spring-link mechanism that generates constant repulsive force at an arbitrary position in the compression and the decompression processes of a stroke. This spring-link mechanism, constant-repulsive-force spring-link mechanism, is able to be useful in various fields. For instance, recently with the increase of the aged, quantity of care that needs a burden of a caretaker increases rapidly. If the stroke of this mechanism can be improved, the quantity of care may decrease. In this study, the combination of coil springs and mechanical linkages, X-link mechanism, is employed to realize such a characteristic. The characteristic that the repulsive force is always constant can be obtained by the combination of two kinds of characteristics : positive and negative spring constants. The stroke of this mechanism can be improved by using the superposition of some X-link mechanisms. This paper presents the improvement of constant-repulsive-force spring-link mechanism.

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In these days finite element method is often used to design and develop products effectively. Using it engineers can evaluate the impacts of design changes without any experiments, so the method which can analyze dynamic characteristics of the much changed structure rapidly is required. Yamazaki and Hagiwara developed the new perturbation method with complementary term for this purpose and showed the possibility to reduce the analysis time drastically, but this method causes the extreme slowing down and instability problems when the structure changed widely. Here, we propose the new complementary vector compute method and the way to calculate responses effectively to solve these problems, and evaluate the accuracy, calculation speed and stability of these methods.

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The purpose of this study is to identify modal parameters of an elevator car by operational modal analysis, and to estimate the stiffness parameters of the elevator car based on the obtained modal parameters. It is assumed that the inertia properties such as mass, the center of gravity and the moment of inertia are well predicted based on the design condition. However, it is difficult to predict the stiffness parameters of an elevator car especially in the operating condition. Therefore, the stiffness coefficients are estimated based on the operational modal analysis in this study. The frequency range of interest is up to 4 Hz, where the assumption that the car behaves rigidly is satisfied. In order to check the assumption the Rigidity Indicator Function (RIF) is introduced as a function of frequency. Frequency Domain Decomposition (FDD) method is used for the operational modal analysis. The stiffness parameters are estimated by minimizing the sum of the errors of natural frequencies and the errors of mode shape vectors between the experimentally identified modal model and the analytical model.

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In this paper, we describe the coupled vibration of oscillators mounted on a plate hanging on four strings and investigate the features of such vibration. From the experimental and numerical simulation results, the following findings were obtained. First, when the natural frequencies of oscillators and their support are almost the same, the amplitude of the support is very small. This is because the driving forces of oscillators are insufficient. In the case of two oscillators, the phase difference becomes almost 180 deg ; in the case of three oscillators, it becomes almost 120 deg ; in the case of four or more oscillators, it becomes variable. Second, when the support vibrates strongly, oscillators synchronize and vibrate with a corresponding phase. Sufficient driving forces of oscillators are required for the large amplitude of the support.

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This study presents experimental and analytical results about the influence of pad chamfering on squeal vibration in the disk-pad-caliper system, which is modeled after an actual disk brake. In the leading side of contact area, the disk and the pad-caliper vibrate with the same amplitude and the same phase at a point. We call this point “contact point”. Chamfering of the pad on the leading edge decreases the sound pressure level of squeal and moves the contact point from the leading side to the center of the pad. On the other hand, chamfering of the pad on the trailing edge has no relation to the squeal vibration. To clarify the influence of chamfering on squeal, we analyzed the disk-pad-caliper system as a surface contact analysis model, which combined the disk with pad-caliper by distributed springs.

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A Magnetic Bearing Wheel (MBW) with inclined magnetic poles which is composed of six electromagnets and six displacement sensors and enables a 5-DOF magnetic bearing, has been developed. This paper deals with equations of motion of the MBW. In general, these equations are formulated in consideration of only the rotor imbalance. However, besides the imbalance, there are actually other disturbance factors in the magnetic bearing and the ordinary equations are difficult to simulate the actual disturbance properties of the MBW. In this paper, the more accurate equations of motion of the MBW are formulated in consideration of all disturbance factors of the MBW including property differences among six electromagnets. In addition, the accuracy of the proposed equations is verified by the coincidence of simulation and experimental results.

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This paper deals with nonlinear liquid surface wave motion in a tank subjected to horizontally and vertically excitation. In theoretical analysis, the fluid is assumed to be incompressible, inviscid, and irrotational. The governing equations of liquid surface wave motion are given by applying the variational principle. In addition, we derive nonlinear an ordinary differential system which govern liquid surface wave motions by using Dirichlet-Neumann operators and the generalized Fourier series expansion. The time histories of surface wave motion are obtained by solving the ordinary differential system. Moreover, the frequency components are observed by applying the discrete Fourier Transform to the theoretical results and the experimental results. The validly of the theoretical result by using Dirichlet-Neumann operators is verified through the experiments.

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In a car crash, if deformation of an occupant's lung is held to the allowable value, no aftereffect will remain. In order to realize this condition, the seat belt tension must be adjusted instantaneously by a feedback control system. In this study, the seat belt tension control system on the basis of the active shock control system is proposed. And the semi-active control law is derived by the sliding mode control method. An advantage of proposed system is requiring no large power actuator because the seat belt tension can be controlled by a brake mechanism. Next, the effectiveness is confirmed by numerical simulation using general parameters of a human thorax and a passenger car in the case that an automobile collided with a wall at a velocity of 100 km/h. Then, the feasibility is confirmed by the control experiment using the scale model of about 1/10. The relative displacement of the thorax model approaches to the allowable value smoothly along the control reference, and it is settled near the target. As the result, it is clarified that the design technique of the proposed seat belt tension control system is established.

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We propose new vehicle dynamics management of in-wheel electric motor vehicle based on tire force usage rate. In the vehicle dynamics management, we adopted non-linear optimizing controller using direct yaw-moment control, tire force usage rate and each tire force. In cornering performance test simulation of 3 degree freedom model, we confirmed that by using this vehicle dynamics management, saturating tire force could be avoided and higher critical speed also could be achieved. We also conducted pylon course slalom test simulation. By this simulation, it was confirmed that the 4 wheel drive in-wheel motor electric vehicle with the proposed vehicle dynamics management system could have higher stability performance comparing to the same vehicle without control.

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In passive suspension for automobiles, the ride comfort and the driving stability are a trade-off relationship. In this study, a semi-active suspension system of variable stiffness and damping is dealt with. For the semi-active control system, a disturbance accommodation frequency-shaped control method is proposed in order to improve both the ride comfort and the handling performance in a higher level. Furthermore, the frequency control needs the adjustment of many parameters in a design of the frequency weightings, but we suggest method of determining frequency weightings by genetic algorithm by can include the evaluation value that can consider both balance in function of adaptation degree. By carrying out computer simulations, it is demonstrated that the proposed method is effective.

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In considering the application of an active noise control system to interior noise reduction of railway vehicles, the control system must respond to changes in the vibration characteristics of the interior panels during train running. We propose a new module-type noise control system, in which small noise control devices are arranged on a plane, to act against the noise transmitted through the interior panel that becomes dominant in tunnels. This noise control system controls the noise incidence to the interior panel, therefore, it is unnecessary to identify the vibration characteristics of the interior panel or noise transmitted through it, and a certain level of noise reduction is ensured irrespective of the change of vibration characteristics of the interior panel during train running. As fundamental work, we carried out a study on the application to the noise transmitted through a flat plate equivalent to an interior panel. This paper first presents an outline of the noise control system and modeling. Furthermore, the overall behavior of the system is examined by numerical analysis, and finally experimental results of the control effect are shown.

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Lost motion is a major disturbance to the contouring accuracy of NC machine tools. Although NC machine tools with plain bearing guide ways perform high alignment accuracy, their lost motion sometimes varies according to motion condition such as position, velocity and moving length, so on. Conventional backlash compensation with constant parameter applied to that lost motion, causes contouring error due to inadequate compensation. This paper presents a model of a two-body system with a position dependent spring and motion condition dependent friction that exhibits varying lost motion, and an adaptive compensation method for that lost motion introduced from the model. Tuning method for the compensation parameters is also proposed. Stiffness of the position dependent spring is calculated from specs of mechanical parts, such as a ball screw, bearings and a coupling, so on. The varying friction is estimated by disturbance observer. Contouring accuracy in a circular test of NC machine tools demonstrates the improved performance of the proposed method.

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This paper investigates an efficient calibration method of 6 DOF acceleration sensor systems using multiple dual-axis accelerometers. So far, we have developed a calibration method to our system as sensitivities of 6 accelerometers were independent each other. But, actually, in dual-axis type accelerometers, there exist some dependency among each axis-sensitivities. Then, we reconstruct a new calibration method to above case, and investigate the influence of the error marging included in calibration. As a result, it is shown that the geometrical errors to be identified which absolute value is small or near 0 compared with other should be assumed 0 from the beginning, and we can decrease the number of calibration data and improve the efficiency of the calibration.

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The purpose of this study is the proposal of insertion type Genetic Algorithm (GA) for the based parameter identification problem of a robot manipulator. An identification problem is one of most important issues in control design for robot manipulators. Generally, the design specifications are given regarding to the controlled variables, which are the output signals of the controlled system. Therefore, it is necessary to discuss the parameter identification based on the controlled variables. However, the dynamic model of the robot manipulator has a nonlinear characteristic with respect to the controlled variables. Then we proposed a new method for the estimated physical parameters of robot manipulator using a genetic algorithm. Since a simple GA is known in some cases to fall into a local minimum and initial convergence, we propose a new GA named insertion type GA. In order to show the effectiveness of the proposed method, a study was conducted. Furthermore, through the simulations and the experiments, the physical parameters of a SICE-DD arm which is 2-DOF robot manipulator are estimated. The effectiveness of the proposed method is confirmed by the simulated results and the experimental results.

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The direction of a generated sound source can be estimated by humans using the time difference between both ears and the characteristics of the sound. However, it is very difficult to create an estimation system using a computer and two microphones. Aims of this study are the achievement of three dimension sound localization with two microphones. We have developed the sound source direction estimation system, in which the sound source direction can be shown by two angles, the horizontal angle α and the vertical angle, β. The former is presumed from the difference of the arrival time when the sound progresses from the source to right and left ear, and the latter is presumed from spectrum correlation analysis using head related transfer function (HRTF). In this study, we propose a novel sound source direction estimation method, in which the feature difference of two recorded microphone signals is used. As a result, an average correct estimation rate of 96% was obtained in determining the location of 11 kinds of object sounds.

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Damping of pressure pulsations in piping systems excited by centrifugal compressors or blowers at blade-passing frequency dominates acoustic resonant characteristics. In this study, the relation between the resistance coefficient of the compressor and the operating point was investigated experimentally. As a result, the resistance coefficient of the compressor depends on the Reynolds number defined by the equivalent velocity of the pulsating flow. It is shown that the pressure pulsations in piping systems can be evaluated by one-dimensional wave model taking into account the damping characteristics of the compressor. The suppression of the pulsation by installing the orifice plate under resonant conditions is discussed in terms of the ratio of the damping force by the orifice plate to the excitation force.

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We developed an experimental device to measure the coefficient of friction of human finger pulp and investigated the influence of three factors (angle of contact with the friction surface, moisture condition of the fingertip, and roughness of the friction surface) on the coefficient of friction. Ten male subjects who had no hand injuries (average age : 23.8 years) were selected. Each subject was instructed to touch the friction plate (acryl plate) using the right index fingertip while applying a vertical force of approximately 20 N and then to slide the right index fingertip at a speed of approximately 5 mm/s. The angle of contact with the friction surface was defined as the angle between the central axis of the finger and the friction plate, and was set to 30, 45, and 60 degrees. In order to investigate the influence of the moisture condition, artificial sweat was applied to the fingertip to simulate three conditions (dry, appropriate moisture, and excess moisture conditions). In order to investigate the influence of the roughness of the friction surface, four aluminum plates processed by straight knurling under different conditions were used as friction plates to produce different surface roughnesses. The maximum coefficient of friction at the start of finger sliding was taken as the maximum coefficient of static friction μ_s, while the average coefficient of friction during sliding was taken as the coefficient of dynamic friction μ_k of the subject. As the angle of contact increased, μ_s and, μ_s tended to decrease, and μ_s at an angle of contact of 30 degrees was significantly greater than that at 60 degrees. No significant difference was observed for μ_k. With respect to the influence of the moisture condition, μ_k for the appropriate moisture condition was significantly greater than that for the dry condition. In addition, μ_k for the excess moisture condition did not differ from that for the dry condition. In the case of μ_s, there was no significant difference between the three conditions. With respect to the influence of the roughness of the friction surface, as the surface roughness increased, μ_s increased, and when the surface roughness exceeded a certain fixed level, it did not affect μ_s or μ_k.

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In this study, a health monitoring system (HMS) for diabetes patient is newly developed. Our HMS fabrication extracts the blood through a micro-needle without a pain and measures the blood sugar level accurately. Main subjects of our HMS fabrication are 1) the minimally invasive blood extraction by using the micro-needle with inner diameter less than 100 μm, 2) the handy type automatic blood extraction, and 3) the continuous measurement of the blood sugar level. We adopts a vacuum type blood extraction scheme. The vacuum driven blood extraction unit consists of a) a puncture part to open the vacuum chamber, b) an extraction part, and c) a measurement part. In the results, the vacuum driven blood extraction unit succeeds in extracting 12.7 μl of human blood within 2 seconds. The blood sugar level is measured successfully by using the glucose enzyme sensor. Therefore, a sufficient operating characteristics of our blood extraction device is confirmed.

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The final goal of this study is to develop the safety palpation-arm structure which satisfies the various kinds of functions demanded for a palpation-arm as a tele-ultrasound imaging diagnosis robot and simultaneously is able to maintain intrinsic safety during its operation. This paper deals with its feasibility study. First, the concept of a safety palpation-arm is proposed, based on a sequence of loadings in motion of a diagnosis robot. Secondly, the framework, which can control the resistance forces of the arm structure according to its concept, is constructed with a skin box beam structure reinforced with skin plates and a trigger causing local collapses. Finally, it is shown by experiments and FEA that the framework is verified to be useful to the safety palpation arm.

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In the present study, mitigation of an intrinsic vibration in human limb called physiological tremor is investigated. The tremor is observed in most human arms even at physically well condition that is derived from excessive stress or chills, therefore, it may cause anyone bad effect on precise operation such as welding and surgery. In this study experiments are performed where the transcription task is imposed on subjects whose wrists are equipped with the dynamic absorber attenuating the tremor in their hands. Good results are obtained where the tremor is reduced to approximately tenth compared with the case without damper. Furthermore, the numerical model of human limbs is introduced, where the tremor is induced by van der Pol type self-excited vibration mechanism. It is also shown that the dynamic absorber can attenuate vibration in human arm despite the intrinsic nonlinearity.

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Dental hygienists are requested to gain skills of dental calculus removal, or tooth scaling. In the previous paper, the authors described development of virtual tooth scaling system and its effectiveness to the skill training. In the paper, the effectiveness was evaluated by the number of artificial calculus removed from a tooth model. However, correct scaling motion has not been evaluated yet. In this paper, for effective training of the motion, two kinds of VR training system are compared with the paint removing method which is adopted conventionally in dental hygienist training schools. One of the VR systems is the one using a HMD as a visual display device. The other is the one using a CRT. As the result, from experiments by apprentice hygienists, it has been clarified that both VR systems are more effective than the conventional method, and the system using HMD is better than the other. This result means that removal force display, and conformity of visual and haptic spaces are important for effective training.

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We propose a new strategy for parallel reinforcement learning ; using this strategy, the optimal value function and policy can be constructed more quickly than by using traditional strategies. We define two types of agents : the exploitation agents and the exploration agents. The exploitation agents select actions mainly for exploitation, and the exploration agents concentrate on exploration using the extended k-certainty exploration method. These agents learn in the same environment in parallel and combine each value function periodically. By using this strategy, the construction of the optimal value function is expected, and the optimal actions can be selected by the exploitation agents quickly. The experimental results of the mobile robot simulation showed the availability of our method.

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In earlier report, the authors carried out surface durability test with carburized steel roller and carburized steel roller with shot peened by two different methods. After examination, some micropitting were observed on contact surface. In this study, we clarified the generation mechanism of micropitting by measuring the geometry of micropitting in detail. The object of the geometry measurement is width and maximum depth of micropitting, and an angle that contact surface and crack formed. According to measurement result, the maximum depth of micropitting was considerably shallower than the maximum shearing stress depth that predicted by cylinder to cylinder contact of test rollers. Further, a strong correlation between the maximum depth of micropitting and the damage width along tool mark was confirmed. Also, the damage width that vertical direction to tool marks was depending on tool mark width which increases along with the contact load. It is thought that micropitting was caused by asperity contact of contact surface after running-in process. Shapes in the radius of curvature of contact asperity were estimated by measurements of micropitting width and depth. The stress analysis was carried out for obtained asperity shape, and stress direction was calculated. Then, the stress that caused micropitting was determined by comparing stress direction and crack propagation angle. As a result, micropitting was caused by maximum shearing stress that increases with high friction coefficient.

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Versatile and reliable techniques for evaluation of hard thin coatings are necessary for the development and tribological assessment of new coatings. We have proposed a new type of slurry-jet erosion test (MSE), i. e. a solid particle impact erosion test, in order to quickly evaluate the wear properties of single layered and multilayered hard thin coatings. In this study, we set up a new type of MSE test apparatus (pot type tester) that can obtain the wear loss per unit mass of erodent (alumina particles with 1.2 11M in diameter in this test). The performance of the apparatus was evaluated using a Si wafer plate under various test condition. In addition, MSE tests of the coatings such as TiN, TiCN and CrN were carried out and discussed concerning their wear loss of coatings per unit mass of erodent. As a result, it generates reproducible results and is very sensitive to the quality of the coating. Thus, it can be recommended as a screening test when evaluating coatings and coated materials.

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Poly (tetrafluoroethylene) thin films were deposited onto a perfluoroalkoxy vinyl ether (PFA) rubber substrate by a conventional vacuum evaporation apparatus. C-F₂ unit can be observed in the FT-IR spectrum of the PTFE thin film deposited at room temperature. However, C-F and C-F₃ units can be observed in the PTFE deposited with heating the substrate at 250°C in addition to the C-F₂ unit. Surface free energies, friction coefficients and pull strength between the PTFE thin film and PFA rubber substrate increased with increase of the temperature of the substrate during the evaporation. These properties are predicted to be related with the thin film structures such as chemical bonding states and cross linking.

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A polycrystalline diamond ball endmill with a radius of 50 m was fabricated by grinding assisted by electric discharge machining to adapt the tool to high-speed machining of cemented carbide having a hardness of 23.8 GPa Hv. A hemispherical endmill with a high tip strength was fabricated by cutting hemispherical tool tip at an inclined surface of 45 degrees. The cutting test revealed that the newly developed endmill, the cutting edge of which was roughened by electric discharge machining with high energy, was effective in preventing tip breakage during high-speed roughing of cemented carbide. In addition, a surface roughness of 160 nm Rz could be achieved when fabricating a cutting edge smoothed by grinding both rake and spherical faces using an electroplated diamond tool of # 600 diamond mesh size after electric discharge machining.

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This paper proposes a method for optimum layout design of cooling channels in plastic injection molding die. The optimum design problem of cooling channels is considered as the shape optimization problem, and the basis vector method is used to determine the optimum design of cooling channels. One of the important factors in molded defects is to reduce the residual stress in the plastic products. The temperature distribution in the die and cooling velocity of plastic will cause the residual stress in the plastic. That is, the two objective functions that are the temperature distribution and cooling velocity are minimized simultaneously. The response surface method based on the Design of Experiment to approximate the objective functions is employed to reduce the computational costs. The weighted sum method is employed to find Pareto optimal solutions. Additionally, the coolant flow is considered, and the effects with and without considering the coolant flow are also discussed. Through numerical examples, it is shown that some curved layouts of cooling channels are obtained.

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Mesh deformation, which is sometimes referred to as mesh morphing in CAE, is useful to provide various shapes of meshes to CAE tools. This paper proposes a new framework for interactively and consistently deforming assembly models of sheet structure for automobile parts. This framework is based on surface-based deformation, which calculates vertex positions so that the mean curvature normal is preserved at each vertex in a least square sense. While existing surface-based deformation techniques cannot simultaneously deform assembly mesh models, our method allows to smoothly deforming disconnected meshes by propagating rotations and translations through disconnected vertices. In addition, we extend our deformation technique so that non-manifold conditions can be handled, because shell structure models often include non-manifold edges. We applied our method to assembly mesh models of automobile parts. Our experimental results showed that our method could deform assembly models smoothly and interactively.

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This development of machines and equipment to make elderly people healthy in their daily lives is important these days. Especially, resistance training equipment is effective for prevention of muscle atrophy in not only healthy adult people, but also the elderly people, and even disabled individuals. Functional Electrical Stimulation (FES) is the artificial stimulation of muscle which have lost nervous control, with the aim of providing muscular contraction and producing a functional useful movement for exercise, standing, and walking. Some authors demonstrated that FES-rowing for persons with spinal cord injury was safe and it also decreased the risk factors for cardiovascular disease. Based on a new concept to effectively restrengthen disused muscles and to enable whole body exercise in seniors or paraplegics, we developed a hybrid power rehabilitation equipment including FES technology. The purpose of this study was to develop a new FES-rowing machine which the elderly and paraplegic patients could use for safe and effective rehabilitation exercise.

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In the progress of elderly society, the gait is important in order to live the independent life. Therefore, it is necessary to evaluate gait analysis simply. Our final goal is to propose the wearable gait analysis. In this paper, we have estimated floor reaction force vector using thin sensor. The floor reaction force vector during a walk is the direction of the body center of gravity. Moreover, the gap with the floor reaction force vector and the body center of gravity generates a rotation moment. We used this specific. Our evaluation method will be useful for developing sensors systems.

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