This paper describes experimental study on the stability characteristics of a rotor partially filled with water. Constant amount of water is supplied to the rotor continuously and is discharged radially by centrifugal force. Consequently, the rotor becomes unstable for some rotating speed range. The unstable speed range depends on the water supply rate as well as the amount of water in the rotor. Formardly traveling surface waves are also observed while the rotor undergoes an unstable orbital whirling motion. The wave travels at the same frequency as the rotor vibration frequency. As the water supply rate increases, the rotor becomes more stable.

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When a strong wind blows a high circular stack, the braces located around the stack vibrated violently. The vibration was induced by winds whose directions are in some particular range. Assuming the flow is potential, fluid dynamic forces acting on a brace are obtained. Dynamic behavior of the brace is analyzed. Analytical results show that the brace vibration may be unstable due to cross coupling spring terms related to fluid dynamics forces. They also agree well with the observed phenomena.

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Using water-lubricated bearings for turbo-machinery is useful for reducing bearing loss. It is important, however, to achieve rotor vibration reliability because the damping coeficient of the bearing that is placed on the far side of the overhung part is reduced. We conducted vibration tests on a motor-mounted rotor to understand the vibration characteristics of this type of rotors. We observed a jump phenomenon of vibration amplitude and sub-harmonic resonance in these tests. We considered that these phenomena were caused by the non-linear characteristics of the water lubricated bearings, and we verified this assumption by using numerical simulations. The calculated results agreed well with the measured results, and we learnt some methods for reducing the non-linear vibration.

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Development for introducing new material technology and new structural design technology in ski poles has been conducted in recent years. Although the CFRP pole is light, the impact is strong. The shock absorbing characteristic of the FRP is important for the application of robot arm and ski pole etc. In this work. the theoretical method was suggested about shock absorbing characteristic. An impact test apparatus was developed for verify the theory and this calculation method. The agreement obtained between the theoretical and the experimental values of seven types of laminated composite cylinders, these being unidirectional (0°, 90°) plies, cross-plies (±15°, ±30°, ±45°, ±60°, ±75°) plies. It shows that the mathematical technique developed here is satisfactory for predicting the shock absorbing values (maximum impact load) of laminated composite cylinders. Shock absorbing characteristic of laminated composite cylinder varies with fiber orientation angle. Effect of E_L is large in near at 0°, and effect of G_LT is large in near at 45°about maximum impact load.

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An effect of the air on the material damping of fiber reinforced plastics has been investigated. As the most of vibration tests are carried out in the atmosphere, however, the material damping has not been evaluated with accuracy. The vibration tests of CFRP plates have been carried out in the atmospheric pressure and in the low-pressure conditions, respectively. Comparing the both of experimental results, the effects of an atmosphere on the natural frequency and damping have been discussed. From these experimental results, it is revealed that the aerodynamic force has a great influence on the damping ratio and the test at below 10³ Pa needs to obtain the real damping ratio. On the other hand, there is little effect of the air on the natural frequency. The damping parameters of CFRP are also identified by the experimental result. These results show that it is important to take the effect of the air on the damping into consideration.

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In order to acquire the vibration information in 2-dimensional space, it was thought that vibrations in two axes should be simultaneously measured using two sensors. When vibration in many directions are measured using the vibration pickup of a single axis, there is no simultaneity between the measured data. For this reason, it was thought that 2-dimensional measurement could not be performed. This paper reverses this common sense. In this paper, the RMS values in three places are measured at time to differ using the vibration pickup of a single axis, and the theoretical elucidation for obtaining the vibrating action in 2-dimensional space only from the measured values is performed. Next, we verify that the theory is correct by measuring the vibration of rotating machine which unbalance has generated. The display method of the vibration information in 2-dimensional space as a combination of elliptical orbits for every frequency component is proposed. On the orbit of vibration with two or more frequency components, the method of determining the rotation direction using the measured vibrating waveform is also proposed.

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This paper compares the results of simplified inelastic analysis procedures to a shake table test of a large-scale piping system which was conducted by Nuclear Power Engineering Corporation. The simplified analysis procedures are based upon different equivalent linearization, and have been developed for calculating the inelastic seismic response of piping systems. Linearization of inelastic load-deformation relationship makes it possible to utilize conventional elastic seismic analysis, such as modeling using elastic beam elements and modal analysis.To linearize the stiffness equivalently, the flexibility factors of the elastic beam elements used in conventional modeling techniques will be modified. As a result, conventional modeling techniques can be easily applied to the simplified analysis procedures. Results of the simplified analysis procedure using equivalent linearization based upon the assumption of white noise excitation agree fairly well with those measured in the shake table test. However, the simplified procedures using equivalent linearization based upon the assumption of harmonic response do not lead to good response predictions.

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Semi-active seismic isolation systems using controllable friction dampers had been proposed to reduce response accelerations and displacements comparing with those of passive systems, although they had a problem that the dampers might fail to generate damping forces due to malfunctions in strong earthquakes. To solve the problem, a new type of controllable friction damper with a fail-safe mechanism was developed in this study. For the damper, piezoelectric actuators were used to make the mechanism simple. The actuators are compact, and can make quick responses and produce large forces. Simulations and excitation tests were carried out for the semi-active system using the friction dampers, showing good performance in reduction of response acceleration and displacement together with higher reliability comparing with systems using conventional friction dampers.

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We have developed a new control method for a shaking table that compensates the reaction force caused by a specimen in real-time. In this work, we executed a series of verification tests to confirm the effectiveness of the developed method with a large-scale shaking table with a payload of fifty tons. The reaction force was calculated from the drive force of actuators and accelerations of the table. A compensator was designed to cancel any reaction force with frequency components ranging from DC to ten hertz. The specimen used for the tests consisted of a 20-ton mass and four columms to support the mass above the table. When the specimen was excited with a large acceleration, the columns were deformed to a plastic range. The characteristics of the specimen, therefore, became non-linear. The results of these tests show that the compensator successfully cancelled the reaction force. Therefore, the control method is effective for using a shaking table with a specimen whose characteristics change during excitation.

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This paper presents an active isolation system with a lightweight table and multi modes of vibration. Then the lightweight isolation table becomes more flexible, elastic multiple modes is appeared within an operation frequency. Therefore, a control system should be designed on taking into account multiple modes. In this paper, the reduced order physical model proposed by Seto is used to design a controller for an active isolation system with the lightweight table and multi modes of vibration. For designing the control system, LQ control theory and double-active control method with feed-forword control are applied. The effectiveness of the control system is demonstrated through simulation and experiment. Moreover, the robust control effect of the system with LQ control theory is verified through simulation when an addition structure is installed on lightweight isolation table.

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In this paper we propose a design method for active seismic isolation control taking account of actuator saturation. By using a hyperbolic tangential function that is differentiable to controller output, we formulate the linear parameter varying system according to the controller output and design a gain-scheduled controller. By carrying out simulations and experiments of seismic excitation, our proposed gain-scheduled controller is compared with an H_∞ fixed controller or a sliding mode controller. It is verified that the proposed controller maintains performance of isolation even if a large earthquake with which the actuator saturation occurs comes, although the other controllers lower the performance than uncontrolled case.

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In this paper, a two dimensional isolation table using circular arc springs and a magnetic damper, which has a simple construction, low height and the capability of vibration isolation in every horizontal direction, is proposed. The isolation table is composed of eight circular arc springs, twelve free bears, a magnetic damper, a table board and a base board. It has approximately the same stiffness and damping coefficient in every direction in the horizontal plane. The trial isolation table was made and its resisting force characteristics were discussed theoretically and experimentally. The seismic responses and the frequency responses of the table installed a mass or a tower-like structure model were measured using an electrohydraulic-type shaking table. The experimental results were compared with the calculated results, and the effects of vibration suppression of the table were confirmed.

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The lateral vibration of elevator ropes for high-rise building, which is excited forcibly by the displacements of the building induced by wind forces, is numerically analyzed, and a new practical method for reducing the rope vibration by using vibration suppressor is proposed for relaxing the restricted elevator operation. Finite difference analyses of the rope vibration with/without vibration suppressor are performed. The advantage of using the vibration suppressors for reducing the rope lateral vibration is demonstrated through the numerical calculation : The resonant position of the rope with vibration suppressor is greatly depends on the position of the vibration suppressor. When the vibration suppressors are uniformly installed along full length of the rope, the maximum rope deflection becomes smaller as the number of the vibration suppressor is made greater. It is also presented that the calculated results of reaction force from vibration suppressor are in fairly good agreement with experimental ones.

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This paper presents the curving performance of railway vehicles with air suspensions. Air suspensions sometimes cause reduction of wheel load at transition curve, so it is very important to evaluate the performance on transition curve and to control air suspensions properly. In previous study it was found that the air suspensions have non-linear characteristics at low speed and that the performance is influenced by the initial condition, the entrance transition curve condition and so on by computer simulation and experiments using one-car-modeled test bench. In this study, the new concept devices, which have functions to make the link rod of air suspension systems extend or shorten, were proposed. The control strategies to compensate the difference of initial condition at the curve entry and prevent the reduction of wheel load at exit transition curve at low speed were also proposed. These proposed control methods were examined by the experiments using one-car-modeled test bench and simulations. As the result, expected performance was obtained so that reduction of wheel load was restraint very much.

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Oscillatory wheel load fluctuation of considerable amplitude is observed on high speed railway vehicles such as the Shinkansen. It is considered to be generated through very small irregularity with short wave length on the rail surface, and the frequency of this fluctuation is estimated to be approximately 50 to 60 Hz. Due to off-loading caused by this oscillation, when lateral forces by curve negotiation act on the wheel flange, derailment quotients in excess of conventional safety criterion, which is set at 0.8, are often observed. In order to study the influence of such oscillatory wheel load fluctuation on the derailment, a computer simulation was carried out using single wheelset model, and then the evaluation method of running safety was investigated. From the results of this calculation, it is found that the external forces and moments to cause derailment are little affected by existence of such high frequency wheel load fluctuation, and that the duration where the derailment quotient continuously exceeds the limit value relates to the height of flange climbing and jumping. This paper proposed a method of safety assessment which is applicable to such conditions.

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The present paper proposes a control scheme for position and attitude tracking of a spacecraft in order to inspect a malfunctioning satellite by maneuvering around the satellite. The proposed method is a nonlinear controller based on the exact-linearization techniques. The exact-linearization method is powerful for controlling nonlinear systems such as the position and attitude control control problem treated in the present paper, because each state variable of the linearized system can be controlled independently. After nonlinear systems are exactly linearized, any kind of control method can be applied to control the systems. The Linear Quadratic Regulator (LQR) is one example of such methods that can be used for controlling the exact-linearized systems. However from the real energy point of view, the exact-linearization method combined with LQR is not optimal, because the performance index is not a function of real energy, and is optimized with respect to the exact-linearized state variables, which are not equal to the real state variables. In the present study, considering the rotational motion of a target satellite, position of the chaser satellite relative to the target and the period of rotational motion of the target satellite, the energy consumption until achieving fly-around motion based on the exact-linearization is minimized. The effectiveness of the proposed method is verified, in comparison with the LQR control or an adaptive sliding-mode control on the exact-linearized system, through numerical simulations.

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PID control schemes still continue to be widely used for most industrial control systems. This is mainly because PID controllers have simple control structures, and are simple to maintain and tune. However, it is difficult to find a set of suitable control parameters in the case of time-varying and/or nonlinear systems. In this paper, a new self-tuning PD controller design scheme is proposed. The PD parameters are adaptively calculated on-line based on the relationship between the PD control law and pole-assignment control law. The proposed scheme is experimentally evaluated on sway control system of a lifted load for a crane. Experimental results illustrate the effectiveness of the new schemes.

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The dynamics of tennis racket has been investigated by many researchers and the relations between coefficient of restitution and stiffness of racket, the center of rotation of racket, the node of vibration were made clear. But they did not consider the energy of motion and vibration. This paper formulated the method to analyze the energies of ball and racket by the modal analysis. The relation between coefficient of restitution and each parameters of racket considering the energy ratios of each mode of vibration was investigated. The characteristic of restitution can be improved by coinciding the striking point to the node of the bending vibration modes, by increasing the mass of racket and by increasing the stiffness of racket. When the rotating speed of racket before impact increases, the striking point must be moved to the head side of racket in order to decrease the kinetic energy of rotational mode.

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Relation between impact force on the automobile lamp and its filament deformation are examined experimentally for accident reconstruction. Filament coil axial impact force and impact force perpendicular to the filament coil axis are applied respectively to two types of automobile lamps, one is the energized low-beam headlight lamp (12 V/55 W) and the other is the energized braking stop lamp (12 V/23 W). And the following results were obtained. (1) For impact force perpendicular to the filament coil axis, curve deformations were examined in both types of the lamp filaments. And in also this case, interrelation between the magnitude of impact force and the coil extension quantity were obtained for the two types of lamp filaments respectively. (2) For the filament coil axial impact force, deviations of filament coil pitch were examined in both types of lamp filaments. And in also this case, interrelation between the magnitude of impact force and the standard deviation for filament coil pitch were obtained for the two types of lamp filaments respectively. (3) The deformation rate for headlight low-beam filaments for (1) and (2) mentioned above using each tests, defined as the ratio between the deformation and the initial condition before the impact, is always larger than that of the braking stop lamp filament.

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The evaluation of an occupant protection device in traffic accidents is necessary to improve its device. Impact severity of a vehicle is one of the most important factors that is related with the injury severity of occupants, however, it was difficult to count for it in case of using statistical accident data because no direct data is available. In this paper, it is shown firstly that the delta-V is a good predictor to evaluate the occupant severity and secondly based on the conservation of the momentum, pseudo delta-V is introduced to evaluate the impact severity in case of applying statistical accident data. New passenger car model introduced into the Japanese market in October 1998 should comply with the regulation which requires occupant injury criteria in side collisions. It was revealed that the regression model that included the pseudo delta-V was better than the model without it. The results of the regression analysis show that the number of fatal or seriously injured occupants in vehicles which comply with the occupant protection requirement is decreased more than the former vehicles.

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This study is research of capsule transport technology of the little type using ultrasonic wave, and developed how to movement two directions of forward and backward movement by giving ultrasonic vibration into a horizontal and small pipe from the outside. The one method is the method of making ultrasonic wave is made to radiate in a small pipe from the pipe end of a small pipe in order to advance a capsule, and advancing a capsule using the radiation pressure. Next method contacts a small pipe to ultrasonic transmitter, shakes a small pipe by ultrasonic vibration, and is a method of moving a capsule by vibration of a small pipe. In this paper, for the beginning the structure of a capsule is shown. Then, the result is reported, because forward and backward movement experiment was carried out using those methods. And, the property of the vibration was examined by the measurement of waveform of applied voltage of the ultrasonic transmitter and vibration of a small pipe. Since a difference and each feature of the two movement methods were considered, the result is described.

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The objective for sound field control is to make acoustic characteristics of a listening room be close to those of the desired system. Conventional methods used to apply feedforward controllers such as digital filters to achieve this objective, however, feedback controllers were also necessary in order to attenuate noise or to compensate uncertainty of acoustic characteristics of the listening room. Since acoustic characteristics are well modeled on frequency domain, it is efficient to design controllers from the view point of frequency responses, but it is significantly difficult to design multi input multi output (MIMO) control system on wide frequency domain. In this paper, partial model matching method on frequency domain was adopted because this method required only sampled data instead of complex mathematical models of the plant in order to design controllers for MIMO systems. The method was applied to design 2 degree-of-freedom controllers for acoustic equalization and noise reduction. Experiments showed effectiveness of the proposed method.

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The authors have recently proposed a new signal processing technique called M-transform. In this paper, we propose to use the M-transform for impulsive noise reduction. Since M-transform of a time signal is equivalent to calculate cross-correlation function between the time signal and M-sequence, both impulsive noise and white noise are converted into small-amplitude random signal through the M-transform. These small-amplitude random signals can be removed by use of some non-linear filter. And then, the filtered signal is transformed into time domain through the inverse M-transform and the noise reduction procedure is completed.The proposed filtering technique is applied to reduce impulsive noise included in surface tracing signal measured by an atomic force microscope. From the results of the experiment, it is shown that the proposed works quite well for impulsive noise reduction.

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In order to realize driver monitoring systems and driver support systems based on the measurement of the driver, it is essential to establish non-contact measurement methods. In this paper, we propose a non-contact measurement system of driver's focus of visual attention by utilizing stereo and omnidirectional cameras. The system measures facial information of the driver such as the head position, orientation and gaze direction in real-time. The estimation of driver's focus of visual attention is achieved in following two ways : For in-car objects such as the speedometer and mirrors, the 3D gaze vector is checked whether it passes through each object. For objects outside of the car, fixation map is generated considering the history of the gaze movement. The feasibility of the methods was verified through measurement experiments of a driver at curve runs and lane changes using the developed in-vehicle measurement system.

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Switches on the steering wheel can be handled more easily and safely with less glance time than those at the instrument panel. The maneuverability of these switches is however not yet studied thoroughly. In this study, shapes and layouts of steering wheel switches for improved maneuverability is presented. From measured acquisition time, the deviation from the target lane, analyzed eyes and hands movement and total evaluation of subjects, the following results were obtained. (1) Switches on the middle and upper area of steering wheel are more easily handled than those on the lower area as used in the cars available in the present markets. (2) For cars with center meter, the upper area of the steering wheel can be used to place the switches. (3) Upon having these switches along the locus of thumb-tip, target switch can be handled more easily with a little glance.

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When we evaluate the driver-vehicle-environment systems, we need to consider the adaptability of the driver. Therefore, in the evaluation of these systems, it is important to consider the factor of the Mental Work Load (MWL) for the driver. It is difficult to measure the MWL directly. Much research on MWL in connection with vital reactions has been done. However, a method of evaluation has not yet been established. In this study, a MWL evaluation is performed using the RRI (R-R Interval), because there is a strong correlation existing between the MWL and the RRI. In order to describe the relationship between the RRI and the factor of the MWL, two kinds of models are constructed. The first model is a static linear model, and the second model is a static nonlinear model. In these models, the RRI of drivers is reproduced. From the result, these models include the relationship between the factor of the MWL and the RRI. Finally, we analyzed the relationship between input and output of the model. The result of that the change of effectiveness is at the entrance and exit points of the curve and the tacking point. It is therefore shown that an analytical method using the MWL evaluation model can be useful for the evaluation of the driver-vehicle-environment system.

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This paper focuses on the tire force characteristics related to the vehicle speed. We constructed a mechanical tire model using a Voigt-Type viscoelastic spring system for the tread rubber. And, we analyze the force distribution along the contact length, the dependence of vehicle speed to the tire forces and the moments to a change in sideslip angle. Finally, it is shown that the tire model has good agreement with actual measurements results qualitatively, and also it is found that the characteristics of lateral force have independence to the vehicle speed.

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In curve design, understanding macroscopic feature that emerges from the combinations of shape elements and controlling it are important. However, it is difficult to understand macroscopic feature using conventional shape-information displayed in computer aided design system. On the other hand, trial and error is required in order to create curved profile reflecting macroscopic feature imaged by designer. We proposed shape-generation method using curvature integration and genetic algorithm, and applied it to the design of automobile side-view. Moreover, the index using multi-resolution representation was proposed in order to consider the influence of resolution on macroscopic feature. As a result, it was confirmed that the control of macroscopic feature in consideration of resolution was possible using proposed shape-generation method and the index. In the present study, it was shown that the possibility of new design-support in curved profile using them.

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The most common commercial pitching machines are the “two rollers” type and also the “arm” type. These machines tend to have certain limitations. In particular it is very difficult to simultaneously change both ball speed and direction. Also some types of pitches, such as the curve or sinking ball, are not easily achieved. In this study, the hardware and software design of a new “intelligent” pitching machine which is able to pitch repeatably with selectable speed, direction and ball rotation, is presented. The machine had three rollers and the motion of each was independantly controlled by a heirarchical neural network. This network accepted ball speed, direction and rotation as inputs and produced detailed motion control of the three rollers as output.

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In industrial applications, a servo controller with state feedback signals generally includes a PID or PI compensator. This controller shows a disturbance robustness to the coulomb friction and gravity as constant disturbances, and thus steady state errors asymptotically approach zero. When the state signals are not available, however, a differentiator is used in the control loop. On the other hand, the use of a differentiator causes phase delays and has a limitation in the control system characteristics. The use of observer basically gives a solution to this inconvenience but, at the same time, loses the disturbance robustness in the original control system. In this paper, the proposed disturbance robust observer designed in a frequency domain is simply described and the overall control characteristics are analyzed when this observer is applied to the system. It is suggested through the analysis that the disturbance response with the robust observer has a disturbance model itself in its numerator characteristics. Finally, the effectiveness of using the robust observer is confirmed by the motor positioning control system.

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In a port container yard, rubber tired gantry crane (RTG) are majority which perform handling the container from a chassis to a yard, or from a yard to a chassis. It has been very difficult to realize automated RTG, because RTG is a large low rigidity crane mounted on rubber tires. We developed new technologies. (1) Image sensors installed at corners of spreader to detect container position directly by the CCD camera. (2) Automatic landing control, anti-skew control, sway velocity observer system. We converted into actual automated RTG and experiment automatic operation system. As a result, we obtained the utilization prospect of automated RTG.

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In this paper, a method of rendezvous docking to an uncooperative target is presented by using adaptive control. When the docking to an uncooperative target is done, the inertia of the combined spacecraft is uncertain. Adaptive control can manage these uncertainties and the asymptotic tracking control is achieved by using backstepping technique in the framework of the globally nonsingular unit quaternion representation of a spacecraft.

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This paper studies a control of the extending flexible space structures. Firstly, it introduces an equation of motion of the flexible satellite by finite element method and shows that it is a linear time-varying system. Then it is represented as a linear parameter varying system and gain-scheduling control method is applied to control it. In order to design the gain-scheduling controller, the method that the scheduling parameters are preserved into a list in advance based on a finite element model, and to reduce the conservative property, the method that the range of scheduling parameters is subdivided are proposed. Finally, because of the constraint of the computer's ability, it is necessary to reduce the model's degree. So gain-scheduling control method by reducing the model's degree is described and even when the generalized plant has the model error, it is shown to be applicable by adding the robust property with the constant matrix scaling. The availability of the proposed methods is proved through numerical simulations.

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In this paper, very simple method based on Prony method, which is known as one of the most representative methods in the exponential analysis method, is presented by which transfer function models for processes can easily be obtained. Here, the method is reformed and applied to obtain the so-called 3 parameter model (first-order transfer function with pure time delay model) from the data of the step response of the process system. The method gives different process models by changing the identification interval. Here the relation between the accuracy of identification and identification interval is considered from the viewpoint of integrated absolute error and integrated squared error. The obtained results are examined by applying it to the design of model-driven PID control of a typical test batch process model.

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A three-dimensional actuator for compensating disc tilt in slim optical disc drives was developed. The actuator inclines the objective lens according to the disc tilt in addition to the focus and track-driving directions. The moving part of the actuator has three driving coils and supported by six suspension bars. Its moving coil structure has the advantage to increase the driving sensitivity. The measured driving sensitivities in the focus, track and tilt directions were 104, 106 m/s²/V and 1.7°/V, respectively. These values are enough for high-speed read-write operation. The result on disc tilt compensation verified the effect of this actuator that the jitter of DVD read-out signal with tilt control was within 10% at 1.0°disc radial tilt.

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A compact and wearable blood sampling medical device applied for Bio-MEM (Biomimetic-Medical Electronics Machine) such as a health monitoring system (HMS), was newly developed. This medical device for Bio-MEM designed by female mosquito's blood sampling mechanism, can extract human blood in order to detect blood sugar level for diabetic patient. This device consists of (1) a bio-compatible microneedle indentation unit using a shape memory alloy (SMA) actuator, (2) a pumping unit using a bimorph PZT piezoelectric actuator and (3) a MOSFET type biosensor by employing Glucose oxidase (GOX) enzyme. The performances of elements were evaluated as ; (1) indentation force of the microneedle using the SMA actuator and (2) blod sampling ability of the pumping unit using the PZT actuator were measured, and the pressure to extract blood by female mosquito was simulated. The indentation load generated by SMA actuator was 0.8 N. The medical device with the PZT actuator, extracted human blood at the flow rate of 2μl/min. The pressure generated by PZT actuator and the simulated famale mosquito's pressure were 11 kPa and 7 kPa, respectively. A Titanium microneedle with the size of a female mosquito's labium (60μm external diameter and 25μm internal diameter) was produced by the sputter deposition method.

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Nowadays the evolution of robots is amazing. However, we cannot make the intelligence and the function of robots higher enough when the work range of robots increases and the contents of work become complicated. Thus, as the strategy to cope with these problems, many researchers are studying the autonomous distributed robot system. The aim of our research is to propose a behaviour planning and a cooperative capture strategy of the autonomous distributed robot system through the examination of preceding studies on “Pursuit Problem” which is taken up as a task of multi-agent systems. In this paper, we demonstrate a deadlock avoidance by making the mobile robot repeat simple behaviors which we propose. We have made some experiments on the simulation system we have built, and the results of cooperative captures are reported in this article.

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In this paper, we propose a wearable antigravity muscles support device, referred to as Wearable Walking Helper, for supporting antigravity muscles on lower extremities, and a model-based control algorithm for the device without using biological signals. In this algorithm, the supporting knee joint moment is calculated based on the antigravity term of necessary knee joint moment, which is estimated based on a human approximated model. The control system is implemented in the Wearable Walking Helper and experimental results illustrate the potential of the proposed system.

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On the basis of an analysis of the interaction between a manipulator for grinding process and a working object in the task space, motions of the constrained dynamic system of the robot is modeled first in this paper. In the model, the constrained forces are included and expressed as an algebraic function of the state and input generalized forces by using the equation of constraints. Using this result, a control law is proposed by taking the advantage of the redundancy of input generalized forces to the constrained forces. A controller for the grinding robot is then constructed according to this control law and without involving any force sensors. Real experiments have been done for evaluating the feasibility of the controller by taking an articulated planar two-link manipulator as an example. Results show the effectivenesses of the proposed controller for real grinding task.

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Piping is used for various places in our life and industries. Recently, since the needs of robots for inspection and maintenance of piping are increasing, mobile robots have been developed in various research institutions. However, a large number of conventional robots were used for piping with larger diameter more than 200 mm, and robots for piping with smaller diameter less than 100 mm are not seen. Furthermore, these robots could not move through any elbow joint and T-joint with right angle or small radius curvature. Accordingly, development of a mobile robot in piping with smaller diameter and various joints, which can apply directly to any pipes laid under ground, in wall, in narrow space and so on, is tried. In particular, in this study, a globular mobile robot with new moving mechanisms and moving algorithms that can move through piping with diammeter about 100 mm is developed. Besides, the robot has vision system, and it can monitor the inside of the piping and detect shape of joint and direction of bend automatically. Finally, the effectiveness of the mobile robot system is verified by moving experiments in piping.

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The object of this study is to establish in vivo measurement system of strain distribution on the human knee ligaments through two processes ; One is to perform in vivo measurement of ligament's deformation and the other is to introduce strain distribution on the ligament by applying the deformation data to an FEM model. This paper concerns with the first process. To solve technical and ethical problems subject to living body, we planned to use less invasive arthroscopy for a measurement. We applied such theory to the arthroscopic images that reconstructs a 3 D shape of an object from its gray scale image. In the experiment, an industrial endoscope was used for its less aberration instead of the conventional arthroscopy. All parametric data necessary for calculation were introduced from the calibration image. The accuracy of our method was checked from known subjects. After that, the anterior cruciate ligament (ACL) of swine hind leg was used for the measurement. Femur and tibia were set on the specially designed fixture. The pictures of the ACL were taken at various knee flexion angles. Three-dimensional coordinal data were obtained by the level set method from the brightness data on the processed image of the ACL. Then three-dimensional shape of the ACL surface was reconstructed.

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We have developed a technique of pattern matching algorithm for estimating pose/position of each tibial and femoral component respectively from its 2 D perspective projection. Yet our pattern matching method should be objected to assess knee prosthetic kinematics and to introduce the contact points' trajectories between the articulating surfaces in order to check and predict the friction and wear conditions on the articulating surfaces. To this respect, the following two kinds of simulation studies were carried out; One was to estimate relative pose/position between the femoral and the tibial components, and the other was to incorporate the 3 D mathematical model of prosthetic articulation into our pattern matching algorithm. The simulation results demonstrated that the estimation accuracy for a relative motion was equivalent to those for a single component, and the 3 D model could not only introduce the contact points' trajectories between articulating surfaces but also improve the estimation accuracies especially for the z-translation.

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It is an important problem that a user can select the adequte wheelchair based on reasonable guideline. However, the method of evaluating the fitting between user and the selected wheelchair has not been established. The mechanical work of the upper limbs and the maximum values of joint torques in wheelchair propulsion are candidates as reasonable criteria of the fitting. In this paper, a new wheelchair has been developed which equips several sensors to measure the dynamic variables on the wheelchair and the upper limbs. It is shown that the proposed criteria, the mechanical work and the maximum torques, can be calculated from the measured variables. Eight persons with spinal cord injury were involved in the experiments of wheelchair propulsion. The evaluated results have been considered in the case when the position of the wheel axis is changed in the experiments. It is verified by the experimental results that the proposed criteria are useful for fitting between users and wheelchairs.

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The purpose of this study is to realize the three-dimensional maneuverability of high speed swimming animals such as dolphins by a biomimetic robot. In the preceding paper, a dolphin robot whose length is 1m was developed, and the loop-the-loop motion in the water was performed. In this paper, a reference trajectory from a start posture to an end posture was firstly planned as a combination motion of roll and pitch. Next, a simulation method to analyze the three-dimensional dynamics of the dolphin robot was developed, and the feedback control for roll, pitch and yaw was examined by the simulation. It was found that the proposed feedback control was sufficient for tracking the reference trajectory in the simulation. In addition, swimming experiments were conducted to examine the validity of the simulation method and the control algorithm. The control performance in the experiments was found to be satisfactory although the optimal feedback gain became somewhat different value from that in the simulation

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Service Engineering is a new engineering idea which aims at increasing service and knowledge contents of added values generated in product life cycle. This report focuses on a service modeling method which is needed in the first step of the Service Engineering. Firstly, we clarify why service should be discussed and argue that intensifying service contents is crucial not only for arriving at environmentally conscious design and manufacturing but also for creating more added values in future advanced societies. Secondly, we present essential concepts of service engineering that is required to intensify service contents. Furthermore, we discuss about subjectivity of service. In general, service is related not only to objective elements but also to the receivers' perception of service contents. In this context, we propose a service modeling method which can represent services with such subjective property of service by clarifying actual service cases.

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Recent competitive economic environments have forced many companies to restructure their organization to maximize efficiency and reduce costs. For such companies, the concentration of various resources upon their particular strong points has become one of their main strategies. Consequently, there has been a rapid increase in the importance of (1) selecting profitable projects from a wealth of possible alternatives and (2) optimizing the allocation of current resources among the selected projects. This paper proposes an optimization system for project selection that not only yields the most beneficial project set, but also the optimum allocation of human resources for the selected projects. The optimization system consists of two algorithms, namely (1) a project selection algorithm for choosing the set of projects that maximizes the total estimated profit and (2) a human resource allocation algorithm for optimally placing human resources among the selected projects, having considered the satisfaction rate provided by the required skills, personal motivation and employee career goals.

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A scheduling problem is formulated in order to consistently manage every production resource such as machine tool, assembly robot, AGV, storehouse, material shelf, and so on. The production resources are classified into three devices, which are producer, location, and mover. This paper especially focuses on a role of buffer, and the differences among these devices are analyzed. A unified scheduling formulation is derived from the results of the analysis based on the role of the devices. Scheduling procedures based on dispatching rules are also proposed in order to numerically evaluate job shop type production with finite buffer capacity. The influence of capacity of bottle necked production devices and the buffer on the productivity are discussed.

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This paper proposes an evolutional changing method of the machine tool performance adapted for production culture in plastic molding manufacturing. The production culture differs from country/era to country/era. Each production cultural sphere needs each survival processing method in belonging the country or the era. So, every specific manufacturing facility performance is necessary to correspond to the vague production culture. In this research, we identify two types of the production culture, the standard type and the variation type. We attend to the later type, in this paper. Then, we propose the method to turn the ambiguous cultural attribute into the required attribute by using a tree structure and more to estimate relation of the required one and the technical one at the quastified dignity with Quality Function Deployment including Analytic Hierarchy Process. As a result, we can carry out the feasibility study of the evolutional changing method to adapt the machine tool performance even for the variation typed production culture.

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