The paper studies how to switch equilibriums of a nonlinear dynamical system by human manipulation. We first develop a bang-bang control technique to switch the equilibriums. Then, we perform an experiment in which human subjects manually produce optimal bang-bang inputs. The result is evaluated by a quadratic cost functional to examine how the human subjects optimize the inputs. It is found that the subjects tend to minimize the quadratic cost functional near reachable areas firstly discovered by the subjects.

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The soft tube like rubber one is easily transformed by the external force of the fluid pressure as well as the spring force. According to the change of the cross section, the vibrations of the fluid flow are sometimes excited. In our study the rubber tube is squeezed solidly over a few millimeters width like an orifice. Under the given supply pressure, there is a maximum point on the flow rate, dependent on the downstream pressure. In the region of positive dQ/dP, the flow vibrations are excited, mostly, downstream of the squeezed portion in the tube. The frequency is close to the natural one of the tube, with the one end open, and the other end closed The characteristics of the flow rate, the variation propagation, and the excitation conditions are explained.

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A dielectric barrier discharge (DBD) plasma actuator has been investigated as a device of fluid by many laboratories. In this study, we try to use it in jet fluids for mixing control. In order to achieve mixing enhancement of jet flow, we focus on two parameters, voltage and frequency of plasma actuator, to examine how induced velocity and turbulence occur. As a result of measuring induced velocity and taking pictures of influenced jet flow, induced velocity tend to increase when voltage is around 6kV and decrease after 6kV, the more turbulence increase, the more jet flow diffuse, has been clarified.

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Characteristics of a plasma actuator driven by direct-current discharge were studied experimentally in a super-sonic flow. The discharge is generated between two small pin electrodes mounted on a Laval nozzle wall with a circle constant cross-sectional area in a Mach 3 flow. Current and voltage measurements indicated the generation of the stable discharge at low power consumption. It was confirmed that the wall static pressure increases beside each electrode and decreases just behind the anode for a 100 mA discharge. Furthermore, the stagnation pressure increment was observed close to the electrode surfaces. It was suggested that the pressure change due to Joule heating of the flow led to the modification of the supersonic flow around the plasma actuator.

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Effects of upstream disturbances on transition of a supersonic boundary layer over an adiabatic flat plate at Mach 2.0 are investigated by means of direct numerical simulation. Spatially evolving transitional flows are analyzed to study the differences of transition process and resultant flow structures due to different dynamics of the disturbances (a first mode oblique wave, wide region random and spot-like disturbances). Simulated flows indicate that streaks and longitudinal vortices are generated as the amplified oblique waves travel downstream. Low-speed streaks, quasi-longitudinal vortices and hairpin vortices are generated in the supersonic boundary layer due to high wide region disturbances bypassing the wave amplification, which closely resembles the incompressible flow. The flows due to the local-disturbances show transient growth flow patterns downstream leading streaks inflectional instability.

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In our previous work, a technique which utilizes a single pressure history from the pressure transducer was proposed to obtain a local Mach number of shock wave propagating in a pipe. In this technique, however, it is assumed that a sensitive head of the pressure transducer is infinitesimal in diameter. Additionally, the strain which is measured at a certain point on a diaphragm of the sensitive head is regarded as the output of the pressure transducer. These assumptions influence accuracy of the scheme. In this study, in order to improve the accuracy dynamic response of the diaphragm is experimentally analyzed. As a result, it is found that not only a posision but also a direction of the strain gauge on the diaphragm greatly affects the initial oscillation of pressure history when a shock wave reaches the pressure transducer.

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We have many small diameter pipes that are gas or water pipes for individual or corporate houses. They must be periodically inspected in order to protect the accident previously. We have proposed an in-pipe mobile robot that is imitated the waving motion of the green caterpillar. The robot is constructed by two somites and three suction brakes. The somites are imitated the waving motion driven by the pneumatic and the vacuum pressures. The robot was confirmed to move in pipes whose diameters are more than 70 mm. The robot is needed the large traction force in the case of the long pipe movement, because it must tow the pressure lines. Now, we investigated the traction force from the mechanisms of the robot. The traction force depended on the friction force of the suction brake and shrinking force of the somite. It was obtained 31 N.

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An inspection of the large intestine is very effective in order to prevent the large intestine cancer. A fiberscope is excellent for the inspection of the large intestine. However, the inspection by the fiberscope often attends many pains and injuring of the intestine. We are hoping the inspecting method for the intestine with no pain and no injuring of the intestine before the operation by the fiberscope. Now, we propose a new microrobot that can surely move in the large intestine in the human body. We need a holding work to the radius direction of the flexible large intestine and a driving work to longitudinal direction of the large intestine.

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We have many small diameter pipes that are cooling pipes for atomic power stations, boiler pipes, and gas or water pipe lines. They must be periodically inspected in order to protect the accident previously. These pipes are different at the place where pipes change from the main to the branch. The inspection robot must move different diameter and generating large traction force for the long distance. We have proposed a snake type in-pipe mobile robot. The fabricated robot is constructed by a moving mechanism and the two brake mechanisms. The robot was confirmed to move in different diameter pipes whose diameters are between 50 mm and 90 mm, generating the traction force of 10 N at 50 mm diameter pipe.

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In our study, our purpose is to give human dexterousness about force sense to robot and we use Jenga game as its target. This paper describes our strategic implementation how robot remove blocks from Jenga tower. At first, we suggest Jenga statics model. A block which can be removed most safely is chosen, using this model. Robot judges that it can remove a block and removes after measuring actual static force and comparing it with model's value.

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An inspection of the large intestine is very effective in order to prevent the large intestine cancer. A fiberscope is excellent for the inspection of the large intestine. Many microrobots that can move in the large intestine have been proposing by several research groups. The actual large intestine in our human body is flexible and has very severe bending curve at the sigmoid. We propose a new microrobot that can surely move in the large intestine in the human body. We use seven rubber bellows in series. Two outer rubber bellows actuators are provided eight bulging rubber sheets. These are called as the braking mechanism. The moving mechanism moves the microrobot by stretching and shrinking. Four rubber bellows are arranged after the moving mechanism in a matrix condition. The microrobot has been confirmed to move from the anus to the cecum in the artificial human's large intestine model.

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For the legged robot on the soft, uneven terrain, landing conditions, such as the posture, of the sole of the leg affect the stability of the robot. This is especially true for the robot working on the sloped soft surface. However, the effective condition has not been examined in the past studies. In this paper, we analyzed the posture of the sole and sinkage and slip on the sloped, soft ground, and introduced a procedure to select the suitable posture.

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This paper presents sensor-based navigation of wheeled mobile robot in outdoor environment. In order to sense its surrounding environment and own location, the mobile robot is assumed to be equipped with a laser range finder and GPS. A potential field method is utilized to create force fields around ob stacles (repulsive force) and goal (attractive force). Look-ahead control is ad opted to steer the mobile robot in which a reference point located in front of the robot is dynamically changed such that the mobile robot is able to success fully maneuver among the obstacles and reach the goal. This approach was adopted to participate in Tsukuba Challenge 2009.

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In the thin steel plates which are used in many industrial products, including automobiles, flaws on the plate surface and peeling during the surface treatment process are induced due to the use of many rollers in the conveyance process. These flaws lead to the deterioration of the quality of the plate surface. To solve this problem, the authors proposed a device for controlled levitation of rectangular sheet plate by means of a hybrid actuator using five electromagnets and thirty permanent magnets. However, it is necessary to consider the optimal placement and number of permanent magnets to decrease the deflection of the steel plate effectively. In this study, we attempt to determine model of attractive force of permanent magnets and number of permanent magnets using the genetic algorithm for a thin steel plate that reduce the deflection and elastic vibration.

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One person ride small fuel cell electric vehicle with a fuel cell of 20W has been fabricated for education use. A student is able to fabricate his own vehicle from basic design. A general fabrication tool such as a hand drill is only used for fabrication. Also general mechanical and electrical parts are used. It is very fruitful to study environmental science using a fuel cell.

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A hybrid electrical wheelchair powered by three energy sources, a battery, a photovoltaic module, and a hydrogen fuel cell is proposed in this paper. The advantage of using a photovoltaic module (a solar panel) is that it produces power without requiring use of fossil fuels. The advantage of using a fuel cell is that a hydrogen tank may be changed quickly and easily. We also propose an energy control system which is able to select the energy source optimally according to the operating conditions. The control system ideally gives priority to the photovoltaic modules before the fuel cell. When conditions allow for abundant sun light, the photovoltaic modules is used. When solar energy is not available, the fuel cell is used. Finally, when the hydrogen is depleted, the battery is used. This paper explains the concept of the hybrid electrical wheelchair, the mechanical design, the energy control system, and the experimental results on the energy source selection.

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An INS is Inertial Navigation System. It is classified broadly into two types, the Platform type and the Strap-down type. Recently, the Strap-down type has been a mainstream. This type is fixed in a moving object. And it is composed of a sensor part and an arithmetical part. The sensor part is mainly composed of three gyros and three accelerometers. And the arithmetical part defines the three-dimensional coordinate system in its inside. One gyro and one accelerometer are set on each axis of this coordinate system. And a coordinate transform matrix is constructed by outputs of gyros. This matrix expresses the posture relation between the INS coordinate system and the Earth coordinate system. And outputs of accelerometers are transformed by this matrix, and they are integrated twice, and consequently the absolute position is calculated. So its position accuracy depends strongly on the precision of gyros and accelerometers. And the precision of them depends strongly on its size. In order to improve the precision, their size must be large. As the result, the size of the INS also becomes large and its weight becomes heavy. So only big size underwater vehicles can be equipped with a high performance INS because they have enough their payload. On such background, we developed a test model of a compact seize INS for small size underwater vehicles. Its performance is real good for its size. In this paper, the main specification and function of the INS is described.

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We develop a mobile mechanism that can move on the surface of the iron bridge for a non-destructive testing device. This mechanism has four-wheel drive and moves by means of magnetic wheels. It acquires adhesion force efficiently by using the principle of the magnetic circuit. This mechanism achieved vertical plane running. Next, we analyze mechanics when the machine approaches a step. It turns out that getting over steps and climbing a vertical plane become possible by selecting the appropriate parameter. It was confirmed by the experiment.

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Generally visual information is used in tele-operation of robots. However, it is difficult for operators to precisely measure the distance only from the picture displayed on a monitor. Therefore, we use not only visual but also force information in tele-operation system for a vehicle type robot. The displayed force is determined by the distance and relative velocity between the robot and an obstacle. The influence of force information on tele-operation was examined by experiment. It was confirmed that the stop point and maximal acceleration of the robot can be adjusted by the force gain and safety rate, respectively.

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This research is about method for estimate the risk for the risk based maintenance of non static equipment based on the monitoring data. Generally, evaluation of probability of failure is conducted by the prediction of the damage based on the hazard data base for the static equipment. But, for the non static equipment, it's damage is mainly caused accidently, so it is difficult to evaluate the damage based on them. Therefore, for the non static equipment, damage evaluation based on the monitoring data is practical. However, the method to evaluate the risk based maintenance on the monitoring data is not established. Then in this research, the method to evaluate the probability of failure for risk evaluation based on the monitoring data is proposed and the validity of the method is experimentally confirmed.

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To reduce interior low frequency noise of a vehicle cabin, damping materials are utilized with low cost and minimum place. But, the panels with high damping interior material and high vibration mode density make matters more difficult to identify the place contributing to the interior noise. In this paper, an optimal local placement of the material considering relative phase between vibration and sound is proposed. In addition, separation of closely coupled vibration modes is proposed by good use of phase controlled multi-input.

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The subject of this research is three kinds of small direct current fan. The causes of the vibration under operation in a small direct current fan are an unbalance and a pressure fluctuation. The vibration is a big problem in the use environment of a small direct current fan, and the vibration reduction of a small direct current fan and the evasion of the resonance are requires. hi this paper, the vibration phenomenon of a small direct current fan was analyzed while operating, and the spectrogram of the object was obtained. The phenomenon was understood by the Experimental Modal Analysis.

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The purpose of the research is a noise reduction of stepping motor. The stepping motor which rotates every step can simply realize position control, and it has the characteristics of small size and high torque. For, high performance equipment, small size and low cost to meet the requirements it was used in a very wide range of applications. However, when driving, a big noise is generated. In this research, it was aimed to decrease the noise by investigating, and improving the cause of the noise by the sound and the vibration analysis. And production finite element model is tried structural modification of entire stepping motor.

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Subjective response experiments were performed to examine the effects of gender differences on uncomfortableness based on subjective response to whole-body vibration. Subjects were exposed to a series of single axis vibration stimuli, the direction of which was for-and-aft, lateral or vertical. Subjects' postures considered in this study were standing and seated postures. Vibration accelerations prepared were 0.2, 0.4 and 0.8m/s^2rms. As a result, regardless of body postures, subjective response values obtained from male subjects were higher than those of female ones in for-and-aft and lateral directions. This result suggests that males feel more uncomfortable than females for exposure to for-and-aft and lateral whole-body vibrations.

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Seismic response of structures is nonstationary random process. Mean square value is one of the representative statistical values, however calculating method for such a response is complicated. In this paper, a simplified calculation method for integral of mean square value of the response is proposed using mean square value of stationary random process.

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In initial-value problems of inviscid Burgers equation with a finite conserved quantity, the weak solution is investigated. It is known that the weak solution asymptotically converges into the N-shaped solution. The analytical expression of the N-shaped solution is obtained as a function of time. Also, numerical computations with the particle method are performed in several initial conditions. In order to verify the accuracy of the solution, the obtained N-shaped solution is compared with the numerical results.

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Recently, large-scale numerical simulation has become possible by improvement of the computer performance and the data of numerical result has become large. Then, some problems arise. When the result data is larger than memory, PC cannot visualize. Generally, large-scale data visualization system transmits all or a part of the result data from server to client PC for visualization. But unstructured grid data is not easy to be thinned out unlike structure grid data because unstructured grid data is not regularly aligned. In this research, we propose a system for large-scale unstructured grid data. Only data necessary for visualization is prepared on the server, and the server sends the necessary data to client PC. Small prototype system was developed and possibility for larger scale data is discussed based on the analysis of the prototype system.

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Induction heating is very high efficiency and safety electrical heating method. The effect of induction heating relies on the magnitude of heating frequency. In low-frequency induction heating, core part of pan's bottom generates heat because of skin effect. It is different from surface heating of high-frequency, and enables near-uniform heating. Induction heating is direct heating, so it mainly has effect of conduction. So part of pan except heating part is not heating very much. Therefore it is very important to design and plan for pan and induction heater to gain the maximum effects. In this study, by numerical analysis of thermal behavior of water in various structures and materials of pans, appropriate condition of low-frequency induction heating was led.

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Nowadays, plastic gears are used in many scene of our life such as domestic electrical products, AV equipments, vehicle parts and any others. And plastic gears are planned low cost, compactable, of high quality. Therefore, it will be used in more various products. But it is known as reaches the damage by the heat that assumed abrasion a cause. Moreover, the detailed mechanism on damage is not solved. The gear's generation of heat, atmosphere temperature, etc. by engagement is considered to have affected the damage mechanism. Therefore, I researched the relationship between heat and gears by the CFD2000 simulation software use the rack model.

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In this study, gas generated with modifying gasification of general wastes is focused on fuel as new use. Thermo Gravimetry and analysis of gas from gasification were performed using waste bamboo from scrap Bamboo Swords and scrap car tire as samples. In TG, from obtained relationship between temperature and weight loss, it was found that each sample had each temperature range of pyrolysis. In gasification, combustible gases were obtained at every sample, and hydrogen-rich gas was produced by modifying with high temperature steam and gas adsorbent.

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We investigated the detailed flow structure between two-parallel disk shape plates to simulate a flow under practical solid oxide fuel cell (SOFC) operation, and tried to improve the flow uniformity by the optimization of flow passage. In the present study, particle image velocimetry (PIV) is used to provide a description of the velocity fields. In the case of applying circle involute shape current collectors, a flow uniformity was achieved over the wide range of Reynolds numbers. An estimation of a fluid motion in the channel was carried out by using Navier-Stokes equations. We confirmed that the velocity component in the flow direction is dominant and plays primary role to maintain a swirl motion.

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The purpose and statistical framework of the model-based approaches in the mathematical process and/or system modeling is presented. Mathematical background of the model parameter estimation as a systematic procedure for the model validation is reviewed. A novel statistical and numerical approach with notion of particles (i.e., particle filter) or population Monte Carlo is explained. Non-parametric numerical statistics is attempted with a general-purpose modeling platform (gPROMS) where empirical distribution functions are simulated based on the measured data. The significance of Bayesian statistical approaches is appreciated with a simple example where non-linear and dynamic models are investigated in terms of the predictive power of each theoretical/mathematical presentation. Model discrimination among the proposed mathematical formulae is attempted with the aid of information criterion statistics such as AIC (Akaike Information Criterion), BIC (Bayesian Information Criterion), or DIC (Deviance Information Criterion). These will not only tell us the best fit of the data but also provide us with the information on even better models.

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Particulate matter (PM) exhausted from diesel engines has several serious effects on human health and the environment. Especially, the strong health effects of the fine particles are reported recently. In this paper, the measurement of the particle size distribution was executed with a low speed two-stroke marine diesel engine. The effect of the dilution ratio in the dilution tunnel on particle size distribution was examined using Scanning Mobility Particle Sizer (SMPS) and Low Pressure Impactor (LPI). The results show that particles in the diameter range from 50 to 100 nm decrease with an increase in the dilution ratio.

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In this paper, the particle size distribution of PM in the exhaust gas from low speed two-stroke marine diesel engine was investigated to know the emission characteristics of the PM. The measurement of particle size distribution was executed by Scanning Mobility Particle Sizer (SMPS) and Low Pressure Impactor (LPI). The effects of the cylinder oil feed rate and the engine load on particle size distribution of PM were examined. Particles of less than 100 nm in diameter decrease with a decrease in cylinder oil feed rate. As the engine load becomes higher, the peak of size distribution curve slightly shifts toward smaller particle size for under 100 nm particle.

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In this paper, an Electrostatic-Cyclone DPF (Diesel Participate Filter) has been newly developed to reduce the Particulate Matter (PM) from a marine diesel engine, and experimented Size distribution of the PM was measured by a Scanning Mobility Particle Sizer (SMPS) and a Low Pressure Impactor (LPI) with four-stroke marine engine (1200rpm, 67.3kw). The experimental results demonstrate that particles of less than 1 μm in diameter account for a major portion of PM and that the DPF can collect fine particles in PM (< 500 nm) from the engine exhaust gas. The DPF shows a high collection efficiency for particles under 200 nm in diameter.

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The present study identified the potential introduction of photovoltaic system by each prefecture in Japan. Using data on the average solar radiation with shading and questionnaire survey on consumers, the authors calculated probability of adopting photovoltaic systems. The system efficiency, a subsidy policy for promoting PV systems and the price of surplus electricity are important factors for new users of PV systems. So, the effect of the electricity price factors on the total PV capacity was investigated.

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In recent years, global warming is put in question. The cause is thought to CO_2 that keeps increasing. When energy is obtained, a large amount of CO_2 are generated usually. So, we paid attention to natural energy as an obtaining means of energy. The experiment examines calorie when sunlight is concentrated on vacuum collector with reflectors, ideal method of setting up reflectors, the structure of the device, and use of obtained thermal energy. It wishes that this device is useful for the problem solving of global warming even a little though the conclusion has not been reached yet.

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The thermoacoustic effect is energy conversion between heat and sound. When heat energy is converted to the oscillation of sound, the heat pump cycle is driven by using that oscillation. As the Termoacoustic refrigerator is an external combustion engine, therefore it has flexbility for selecting the heat source, working fluid, and the mechanism is so simple. In this work, the energy flow for thermoacoustic refrigerator was calculated to clarify the energy efficiency. About 70% of the input heat was transferd by the sound flow and radiation. When the orifice was inserted in the tube to reduce the heat transfer by sound, the efficiency was improved.

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In general, when the high temperature circular or rectangular channels are cooled by forced convection of gas, there are several methods for enhancement of heat transfer such as attaching radial or spiral fins on a channel surface or inserting twisted tape in a channel. The objective of this study is to investigate heat transfer characteristics by forced or natural convection of porous materials inserted into a rectangular channel with high porosity. In order to obtain the heat transfer characteristics of the one-side heated vertical rectangular channel inserting the porous material, an experiment was carried out. From the results obtained in this experiment, it was found that an amount of removed heat by forced convection using porous material (porosity > 0.996) was about 10% higher than that without the copper wire. Furthermore, the ratio between the amounts of heat removed of the rectangular channel with the porous material and without the porous material increases with increasing temperature of the channel wall.

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The present study investigate the effect of angle change of the airfoil flap on the amount of power generation, and also examine the minimum starting velocity of the wind. The conclusion obtained are followings. The generated electric power using the flap wing is possible keep the optimal condition by changing the flap angle appropriately for high wind velocity. But it is better to keep low angle for low wind velocity. For wind velocity of 4〜14[m/s], the flap angle 25° is found to be best (optimized) value. Efficiency of power generation for flap wing without fixed angle (free condition) is almost same as that of the optimized value (25°)under fixed angle for condition.

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The study examined many problems such as efficiency improvement or the safety noise of a windmill for small vertical axis model wind-generated electricity to be called" a Cygnus Mill". The quantity of generation increases as I raise number of revolutions, but there is a threat that I have bad influence such as a fall of the safety or the increase of the noise. Therefore I examined a condition to improve performance and efficiency without raising number of revolutions. I changed a wing-shaped installation angle in one's study in various ways and measured it and tested it. As a result, I added an installation angle and understood that a change had an influence on quantity of generation and efficiency to a minus. (1) As an attack angle rises to a minus, the circumferential speed ratios decrease. (2) As an attack angle rises in a plus, the circumferential speed ratios increase. (3) In the case of wingspread 1,000mm, an attack angle degree understood that time of 32 degrees was quantity of greatest generation. (4) In the case of wingspread 1,500mm, an attack angle degree understood that time of 35 degrees was quantity of greatest generation.

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The spread of the large size wind turbine is not advanced due to the wind synopsis and the problem such as geographical condition in Japan. Then, small size wind power generation used a small size wind turbine are thought as one choice to break such a situation. In this paper, it is proposed to develop the small wind power generation system used Torsion Arc Blade Type (TABT) Horizontal Axis Wind Turbine developed originally, and to put it to practical use. As for the TABT horizontal axis wind turbine, the rotor blade is composed by stainless rectangular thin plate. The both ends of stainless plate are fixed to the rotational axis like the circular arc with the angle of 30° for the wind direction. In steady flow, the various characteristics of the wind turbine are clarified. Moreover, the wind turbine was set up in outdoor, it experimented on the field, and the wind power generation situation was examined.

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A Savonius Rotor is low efficiency. But it is considered that the windmill is suitable for the use in the city area because it can make the projection area looked from the upper part small. In this study, we focus attention on its blade shape, and examine influence on efficiency improvement from torque, blade surface pressure distribution and flow visualization on static condition. The blade shape is four blade types of blade height. As a result, there was not much difference of pressure and flow on four type blades, but there was difference of torque. It is considered that key factor of the difference is geometric influence.

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Our research object is a cycloidal propeller to be installed in an airship. Since cycloidal propellers have abilities to control the thrust and its direction immediately and simultaneously, the high performance thrust control can be expected to give airships more agility and various utilities. In designing a cycloidal propeller it is very important to investigate the thrust and power efficiency in relation with the propeller structure. Our aim is to clarify effects of wing-lets, number of wings, and angle of attacks of cycloidal propeller. Moreover, we have carried out indoor test flights of an airship equipped with cycloidal propellers and evaluated its ability of manual flight.

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The seed of Ash tree has a thin and long-shape, whose span is about 41.7[mm] and weight is about 0.05[g]. When the seed fall, it rotate in two directions. One rotates in span-wise axis and other in radius-axis which located at center of gravity. Aerodynamics force acting on the seed was experimentally studied at lower Reynolds number range. Smoke visualization and pressure measurement were performed using a spinning thin plate model in a vertical low-speed wind-tunnel, and the flow mechanism around the spinning plate is also discussed.

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In this study, we propose a musculoskeletal model that can investigate the mechanical properties of the ACL (Anterior Cruciate Ligament) as a function of knee flexion angle. The knee joint in the model is more detailed modeling introducing the contact conditions of the knee joint surfaces, i.e. the knee joint surfaces are capable of the relative motion such a sliding and rolling during flexion or extension The inverse dynamic analysis was used to investigate the ACL mechanical properties under the influence of muscle recruitments. As the results of the analysis, ACL length decreases with increasing flexion angle and, at less than 30°, ACL tension rapidly increases with increasing flexion angle, subsequently tension decreases. For the future, we need to improve the modelling by introducing patella and mimic viscoelasticity characteristics.

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Recently, the number of foot joint syndromes by an acquired transformation increases. Because loading condition and the structure of foot joint greatly influence them, the clarification of the mechanical property of foot joint is important. Especially, a flatfoot has a lot of patients as an acquired case. In this research, the bone in the arch of a normal foot and a flat foot was reproduced by three -dimensional model, the stress distribution was analyzed by the photoelastic investigation, and it made comparative study of them. The experiment analysis result showed the following things. The remarkable difference was seen by calcaneus. In ground plane, stress concentration caused the normal foot inside. Stress decreased as the normal foot went outside. On the whole, stress increased the flatfoot. And, reduction of the stress in an outside like a normal foot was not seen.

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In the fields of the medical welfare and sports, it is required to evaluate the deformation characteristic of muscles. But the properties of the biological soft tissue like muscle depend on the surrounding environment. So it is necessary for in situ measurement of the muscle properties. In this study, we built the movement model of human arm and the constitutive model of the muscle, and we adopted the method of the viscoelasticity evaluation of the muscles in human arm by the measurement of muscle force and SEMG. Then, we try to construct the measurement system of the properties and examined the time response of the force and SEMG by the application of the system to human arm.

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Made a Simulation model of forearm including elbow joint, proximal and distal radio-ulnar joint, was produced on virtual space from CT and MRI data in this study. This model consisted of bone, ligament, and muscle component. Simulation model changed setting of a ligament, and compared each generated model movement, and MRI data, and inspected the method for construction of simulation model with clinical application, and a function of each ligament. As a result, the simu- lation model was able to generate flexural movement on virtual space. And, from comparison of each model movement, a restriction state of an Medial collateral ligament influenced in stability of elbow movement. In addition, Lateral ligament complex, errors of model movement was increased by annular ligament rupture or rupture of a ligament supporting it.

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