The current footplate type side slip tester measures only the total side slip. Therefore, measurement techniques by which to determine the side slip for each alignment element was examined. Concretely, because the side slip related to the camber angle varies depending on the unit load per travel wheel and the side slip related to the toe angle depends only the direction of the tire and not on the unit load per travel wheel, the side slip for each alignment element can be determined separately.

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Adaptive line enhancer which is one of the application of adaptive digital filter can extract only periodic signals buried in a broad-band noise, under the condition of the frequencies of the periodic signals are unknown. However it is known that adaptive line enhancer gets impossible to remove noise for a certain period after a strong pulse noise is put to the adaptive line enhancer with input signal. In this paper, an adaptive line enhancer by using wavelet transform is proposed to get over the problem. Here, discrete wavelet transform is used for the proposed method, however, the discrete wavelet transform based on multiresolution analysis has a demerit of the lack of shift invariance inevitably. Hence considering the demerit of discrete wavelet transform, in this paper, redundant discrete wavelet transform is used which realizes the shift invariance. The effectiveness of the proposed method is shown through simulations. Moreover voice signals that are sampled from human voice are used in simulation to remove noise to show the effectiveness of the proposed method even for voice signals.

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We developed a diagnosis method for unsteady rotor vibration using vibration repetition calculated from the results of wavelet analysis. In previous research, we compared measured vibration repetition with pre-measured abnormal vibration repetition. To improve the reliability of the diagnosis, we used differential vibration repetition, which is calculated by subtracting pre-measured normal vibration repetition from measured one. We measured abnormal vibration and applied the diagnosis method to the measured vibration, to determine the reliability of the method. An unsteady natural frequency vibration started, when rubbing on a rotor occurred. As lubricant in the bearings was reduced, a steady natural frequency vibration occurred, and it changed to an unsteady low frequency vibration. A steady super-harmonic vibration occurred when most of the lubricant in the bearings was absent. The reliability of the diagnosis was improved using deferential vibration repetition.

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This paper deals with an optimal control of non-linear mechanical system. In this method, the functional consists of total energy of controlled system, performance function and energy function. This energy function is described by energy flow which is transmitted from controller to controlled system. The functional is described as a first-order expression concerning with control variables, therefore it is able to induce optimal control law from the condition of minimizing the functional. This method was applied to the control problems of the energy regenerative active suspension and of the nonholonomic system. As a result, it is clarified that this method is useful to design controllers for energy regenerative control systems and nonlinear mechanical system.

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A new algorithm using image operation was developed for identifying and tracking a natural vibration mode that is one of the most important factors in structural design. It enables the automatic survey of parameters in the vibration design of structures even when mode switching (crossing) occurs. Mode switching is the change of order in which natural vibration modes appear. The developed algorithm performs the following tasks. First, the absolute value of each component of a vector corresponding to a natural vibration mode is represented as a gray-scale image by a post processor. Each of the gray-scale images is then binarized. The numbers of groups consisting of pixels with the same color are counted in each binary image, and the numbers are used for distinguishing the natural vibration mode to be tracked from the other modes. A structural optimization system was developed. It consists of the software routine using the developed algorithm, a commercial optimization software, pre and post processors, and a calculation solver. The effectiveness of the algorithm using a cantilever plate whose natural vibration mode appearance order varies in changing the design parameters was tested and verified. A new reinforcing rib was then added to the cantilever plate that requires re-meshing. The effectiveness of the algorithm was also tested and verified on the modified plate.

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Active microvibration control is expected to be applied to floors and even entire buildings of precision manufacturing facilities to meet requirements for more perfect vibration-free environment in the facilities. It is desirable that such facilities are effectively protected from earthquake attacks by using seismic isolation. For base-isolated precision manufacturing facilities, comprehensive active microvibration control systems were studied to control both of microvibrations born in the inside due to equipment and human walks and microvibrations coming from the outside due to ground vibrations and winds. A base-isolated 2-story building model of a 3m×5m×4m^H external size and a 6.9t total mass was used for experiments, in which 4 multistage rubber bearings and a viscous shear damper were installed for the seismic isolation, while 20 piezoelectric actuators were attached to the columns and the beams and 8 piezoelectric actuator units were installed in the seismic isolation layer for the active control. The tests showed that the system consisting of the passive base-isolation system and the piezoelectric actuators attached to the columns and the beams could most effectively control the three-dimensional microvibrations due to the external and the internal disturbances.

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We developed a computer program to analyze the coupled vibration of lateral and axial vibrations in rotating machines by using the quasi-modal transformation method. This method is based on the same concept as the well-known modal synthesis method. The method provides a reduced model of an actual system using a combination of eigen modes from an inner system restricted at the bearings and deflection modes created when a load is inputted at the boundary points. Lateral vibration and axial vibration models were reduced using this method, and the reduced models were then combined at the bearing boundary points. We can rapidly obtain accurate numerical analysis results of coupled vibration of rotating machines, like turbine-generator sets, by using this program. We showed the practical applications of our method by comparing the numerically examples with a non-reduced model. We also showed that the natural frequencies of axial modes decrease because of coupling in the lateral mode.

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This paper presents a novel method for constructing the PD-type anti-windup compensators for a general class of linear systems with input saturation. Having derived the stability condition of the whole control system, this condition which is described by a matrix inequality is transformed to an LMI from which the compensator gain matrices can be determined. The usefulness of the proposed design method is verified successfully by a numerical example.

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A new approach of modeling and control for the tilting-ladle-type automatic pouring process is proposed. The flow rate model is described by nonlinear systems with hydrodynamics. The pouring control system is built by a feedforward control using inverse dynamics of the proposed model. In the control system, control parameters without a flow rate coefficient are obtained from configuration of the ladle, and the flow rate coefficient can be identified by doing experiment only one time. By using the proposed pouring control system, the actual flow rate of the outflow liquid from the ladle could be precisely approximated to the desired flow rate. A proposed system is applied to the tilting-ladle-type automatic pouring system with a cylindrical ladle, and then the effectiveness of the system is shown in experiments.

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In this paper, we examine the parametrization of all stabilizing multi-period repetitive controllers with the specified input-output frequency characteristics. The parametrization of all stabilizing multi-period repetitive controllers was considered by Yamada et al. However, when we design a stabilizing modified repetitive controller using the parametrization by Yamada et al., the input-output frequency characteristics of the control system cannot be settled so easily. From the practical point of view, the input-output frequency characteristics of the control systems are required to be easily settled. This problem is solved by obtaining the parametrization of all stabilizing multi-period repetitive controllers with the specified input-output frequency characteristics. In this paper, we expand the result by Yamada et al. and propose the parametrization of all stabilizing multi-period repetitive controllers with the specified input-output frequency characteristics. The roles of free-parameters in the parametrization are also clarified. Then it is shown that the input-output frequency characteristic and the disturbance attenuation characteristics can be settled independently.

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When developing sheet-handling machinery, it is important to be able to reliably predict the behaviour of the sheet. For automated teller machine, in particular, a dynamic analysis of the deformation of each sheet is needed to predict the behaviour of the sheets that will be fed at high speed. Accordingly, we have developed a simulation system that can predict the behaviour resulting from various sheet conditions by means of FEM. To predict the sheet behaviour with high accuracy and efficiency, we identified several sets of sheet conditions and guide configurations that likely cause problems by analysing the results of sheet transport tests. We also save an example of sheet path design for the sheet handling apparatus which proved that the simulation system is useful for designing sheet path.

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The swing of a ropeway gondola is easily induced by wind and can be reduced by a dynamic absorber. To maximize the performance of conventional dynamic absorber, their location should be as high as possible. However, absorbers can not be located at high positions due to interference issues with structures such as towers and stations. To solute this problem, a new type dynamic absorber is proposed in this paper. It reduces a swing of gondola, by making use of Coriolis force which moves in the radical direction. This absorber is more effective when it is located at lower position. The damping force of conventional absorber is proportional to the amplitude of the vibration of main mass, however, the Coriolis force is proportional to the cube of amplitude. Therefore, it is more effective when the amplitude of gondola is larger.

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In identifying machines and structures, one sometimes encounters cases in which the system should be regarded as a nonlinear continuous system. The governing equations of motion of a nonlinear continuous system are described by a set of nonlinear partial differential equations and boundary conditions. Determining both of them simultaneously is a quite difficult task. Thus, one has to discretize the governing equations of motion, and reduce the order of the equations as much as possible. In analysis of nonlinear vibratory systems, it is known that one can reduce the order of the system by using the nonlinear normal modes preserving the effect of the nonlinearity accurately. The nonlinear normal modes are description of motion as nonlinear functions of the coordinates for analysis. In identification, if and can express the data as nonlinear functions of the coordinates for identification, it is expected that accurate mathematical model with minimum degree of freedom can be determined. Based on this idea, this research proposes an identification technique which uses nonlinear principal component analysis by a neural network. Applicability of the proposed technique is confirmed by numerical simulation.

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An eddy current testing (ECT) probe is used for a diagnosis of a helical heating tube installed in a fast breeder reactor, and a vibration of ECT probe makes the diagnosis difficult. In our previous report, we proposed an analytical model of the ECT probe incorporating with a fictional force and confirmed that the vibration was caused by Coulomb friction. In this paper, it is shown that numerical simulations utilizing the analytical model agree with various experimental results of the vibration of ECT probe, so that the reliability of the analytical model and the numerical simulation is increased. It follows that a preceding estimation of the vibration is available by the numerical simulation. Based on a behavior of the entire probe, which is obtained by the numerical simulation, we discuss a countermeasure to suppress the probe vibration. The validity of countermeasure is demonstrated through the numerical simulations.

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A numerical algorithm to solve a nonlinear fractional differential equation (NFDE) which includes the fractional derivative of the first and the second power or displacement is developed. These displacements are related to the linear and the nonlinear dynamical viscoelastic behavior. Derivation of the numerical integration algorithm by the use of one-step scheme of Newmark-β method, error evaluation and some important parameter studies for a typical numerical model are given. The characteristics of the linear and the nonlinear fractional derivative responses for ramp input, and of the nonlinear viscoelastic responses of the NFDE for sinusoidal input are investigated. From the study, the developed numerical algorithm is validated to solve the NFDE.

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A method is proposed to estimate the sway angle for an overhead crane by an unknown-input observer using data from angular velocity sensors. Characteristics of this observer are as follows. (1) It is not influenced by system elements that are difficult to identify. (2) It is designed to minimize influence of a higher frequency vibration caused by the pitching motion of the load. Furthermore, estimation of the sway angle is possible even accompanied with a torsional vibration of the rope. By means of a measurement system with this observer, some experiments to control the sway angle of the load and the position of the trolley are carried out. The result is successful in keeping the sway angle in zero near the objective position. In this way the validity of the method to estimate the sway angle using angular velocity sensors is verified.

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Generally, the friction force is considered as a constant value. However, it has been shown that the friction force depends on the displacement and shows hysteresis loop in the region of the initial rolling displacement. Hence, it needs to consider the friction force depends on the displacement when dealing with the realistic problems. In this study, we use a curve of the starting rolling displacement, which consider the region of the initial rolling that the rolling friction force depends on the displacement, and make an analysis of the vibration of a one degree of freedom system with the rolling friction. In the numerical analysis, the stop motion is generated in the condition below the resonance point. Meanwhile, it is clarified that the stop motion is almost not generated and the vibration wave shows a sine wave clearly in the condition more than the resonance point. The parameter m that shows the loss energy of a system in a curve of the starting rolling displacement greatly affects the vibration characteristics, and the different characteristics appear in the case of m≥2 or m<2.

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In recent years, security problems have been concerned in the well-developed information society. Although personal authentication methods such as password-systems and key-systems are used widely, various problems are pointed out. Therefore, biometric authentication which uses the information of physical or behavioral characteristics is becoming important technology as a personal authentication. In the present study, a new biometric authentication system using finger-friction is proposed. This system utilizes tactile information of which recording and playing technologies have not been established, in contrast to visual and auditory information. Moreover, it is using both physical characteristics related to the 3-D shapes of fingerprints and behavioral characteristics related to the way of rubbing. In the present system, an array-structured sensor generates 12-channel frictional signals which are distinctive to an individual when a subject rubs it with a finger. In the present paper, 100 samples of frictional signals are used for verification which is based on dynamic programming. As a result, improvements of verification algorithm make it possible to reduce False Rejection Rate (FRR) and False Acceptance Rate (FAR) to 1% and 0.05% respectively.

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This paper deals with response reduction effect by friction behavior. Friction is expected to absorb seismic energy. This effect should be utilized positively in seismic design. For past several years, seismic isolation structures have been focused in seismic design of industrial facilities. Seismic isolation effect is controlled by the friction characteristic exists in friction support. Therefore, adjustment of frictional force becomes a very important. In this paper, “Response Reduction Map” for long period friction system is suggested. This map shows the range that response magnification is less than 1 and less than the response of linear system. The response reduction map without complex non-linear time history response calculation can easily obtain the response magnification. At first in this study, the response reduction map by actual earthquake wave is shown. Next, the response reduction map by the artificial earthquake wave calculated using design spectrum is shown.

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This paper studies the stability characteristics of tilting-pad journal bearings theoretically and experimentally. A tilting-pad journal bearing floating on a rotating rigid shaft was found to turn unstable beyond threshold shaft speeds, whirling with a subsynchronous frequency in the conical mode. The threshold shaft speeds were theoretically obtained for various operating conditions with the angular stiffness coefficients and the angular damping coefficients of the oil film due to the tilt motion of the bearing being considered. The predictions were found to agree well with measurements qualitatively. This unstable vibration of the bearing results from the cross-coupling terms of the angular stiffness coefficients much larger than the direct terms at higher Sommerfeld number. The threshold speeds were found to be insensitive to the variations of preload factor, which is contrary to the case of the parallel mode oil whip.

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Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The SAW linear motor has several advantages, such as thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, had non-linearity in low velocity range due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control at low velocity. To realize low velocity, PWM (pulse width modulation) control and flexible slider structure are employed. The flexible structure is installed to cancel vibration due to PWM carrier frequency. In this research, PWM is applied for controlling the slider velocity. Lower velocity in non-linear range is realized. Influence of the flexible structure upon precise positioning is investigated.

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As to a train running at high speeds in tunnel, the car-body vibration increases considerably and the riding comfort is deteriorated. In tunnel sections, aerodynamic force is generated around the car body and it makes the running vibration bigger in sway and yawing modes of car body than that in open sections. On the present Shinkansen trains, “longitudinal inter-vehicle dampers” have been installed to improve the riding comfort of passengers. With other stiffness or damping devices installed between adjoining vehicles, more improvement can be expected in the riding comfort at high speeds. However, if the restriction between the vehicles is too strong, the curving performance may get worse on sharp curves such as turnouts laid in station or train depot, on which trains have to pass frequently. In this paper, an analytical model of a train is developed to simulate the running behavior of connected vehicles. And numerical simulation is carried out to examine the riding comfort of a train running at high speeds and also the curving performance through a turnout, varying the stiffness and damping between the vehicles. A potential, in which the ride comfort improves without increasing wheel lateral force on sharp curves, is found in the condition that the inter-vehicle damping is increased in longitudinal direction and added at lower position in lateral direction.

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Optimal steering and braking control for automobiles in emergency obstacle avoidance situation is investigated. The obstacle avoidance problem is formulated as a nonlinear optimal control problem to minimize a performance function consists of the time integral of squared tire workload and control effort. A numerical optimization method is applied to calculate the optimal steering and braking inputs. The optimum controls are calculated for several distances to the obstacle. The relationship between distance to the obstacle and the maximum initial velocity to enable the obstacle avoidance is investigated. From these results, the optimal usage of the control inputs in emergency obstacle avoidance situation is discussed.

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The aim of this study is to explore the right position for installation of a visual display of Car-Navigation system. The method of this research is to consider about the effects of installing a display on the visual information processing of driver from the experimental approach. The evaluation indices are measuring the saccadic time, the stationary time and the visibility time from the movement of the subject's fixation point. The results shows following : (1) It is proved statistically that the position for installation of a display effects the saccadic time, the stationary time and visibility time. In addition, the longer the distance from the glabller point to the position for installation of a display becomes, the bigger the visibility time is. (2) The reason why the effect of the vertical installation angle on the visibility time is lager than that of horizontal is dependent on a property of the saccadic movement and the region of the useful field of view. (3) The estimated equation that shows the relationship between the position for installation of a display and the visibility time is proposed.

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The final goal of this study is to construct safety structures for medical and human-car robots and moving equipments. This paper proposes a concept of the smart structure applied to them that has an ideal load-deflection curve for the safety design. An experimental study on the denting and bending of aluminum skin tubular beams and ways to control the load-deflection curves with various reinforcements and triggers was carried out as the first step of the goal. Experimental results on simply supported tubes show that a simple skin model for low load design and a double skin model for high load design have each ideal structural property considering from a viewpoint of high initial rigidity, peak-load control, high buffer efficiency and configuration reversibility. One of three kinds of reinforced skin tubes that are able to construct the ideal load-deflection curve with a ring-shaped trigger is proposed to be of most practical use for cantilever models.

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A finger component was modeled by four tendons of three extrinsic muscles and an intrinsic muscle attached on a two-dimensional three rigid links of finger skeleton. Moment arms of each tendon were assumed constant regardless of joint angles. Each muscle generates not only active force but also passive force as a function of changing of muscle length. By judging the capability of moment balance under given finger posture within the limits of each muscle force, the range of motion and the maximum fingertip force were estimated. These results of the paralytic finger were agreed well with the clinical experience. Postoperative effects for two common tendon transfers (Lasso procedure and Four-Tail procedure) were simulated. For Four-Tail procedure, one of the following muscles was selected as a motor, palmaris longs, extensor carpi radialis longus, extensor carpi radialis bervis, and flexor digitorum superficialis of ring finger. The functional defects caused by transferring these wrist muscles were evaluated with the decreasing of total maximum moments of the wrist joint. Calculated results suggested that Four-Tail procedure with extensor carpi radialis longus was superior to other procedures in restoration of both range of motion and fingertip force. It was also found that Lasso procedure corrects fingertip force well.

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We developed the SMO (Spastic Measurement orthosis) in order to measure the feature of spasticity by the paralysis of stroke. Because we focused on patients suffering from hemiplegics stroke in order to develop a design method of an AFO, which fit patients even more. Experiment method : Experiment system was consisted combining 3D Video Tracking system of 12CCD-camera and 8 force plates and SMO. Subjects of the experiment were conducted by healthy person and four stroke persons. Each subject who wore the SMO walked on the floor reaction force by usual walk. Experiment Result : Each subject's ankle joint moment was calculated and these experiments data were evaluated by comparison of the moment of SMO and foot angle at the Heel contact, paying attention to heel contact required for orthosis prescription. The possibility in order to determine of requirements for the design orthosis was suggested from these experiment results

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It is heavy jobs to change diapers for bedridden patients. Changing diaper hurts prides of the patient, so that a panty-type toilet, that can be worn to the patient, is of importance, in which feces and urine are washed automatically. In this study, a new-type automatic washing panty type toilet system is presented. The system consists of a rubber made panty type toilet with tubes at both thighs and a torso, and a control system. In the toilet, air expands the tubes, and water leakage is prevented when washing water flows in the toilet. In the toilet, moisture is dried by dry air and controlled to be an appropriate value. There are three important problems in the system, one of which is the prevention of water leak from the panty-type toiled, second is the method of detecting urine and moisture, and the other is the method of control of the tube's grip pressure to the thighs and the torso, because the pressure gives pains to the patient when its value is larger than the appropriate pressure region. The toilet and the control system are constructed, and experimental tests have been performed. It is ascertained that the proposed system is applicable, in principle, in practical use.

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Three-dimensional (3D) microstages driven by electrostatic comb actuators that provide continuous motion along three axes (x, y and z) were fabricated and evaluated using AFM (atomic force microscope). The 3D microstage consisted of sets of traveling tables, suspension systems, and comb actuators. Support suspensions were adoped to support two sets of comb actuators to exclude the interferences between the combs and to increase the displacement of the traveling table. The 3Dmicrostages were fabricated in a 20-μm-thick device layer on an SOI (silicon on insulator) wafer by using DRIE (deep reactive ion etching). An AFM was then used to operate the 3D microstage as its scanning devise. By measuring the grating on the traveling table, the relation between the displacement and driving voltage on each comb actuator was examined. The displacement of traveling table was 5μm in the y direction at a driving voltage of 40 to 225 V, and was 4.8μm in the x direction at 70 to 140 V. The displacement in each x and y direction is proportional to the 1.8th and 1.5th power of the driving voltage on each comb actuator, respectively. No hysteresis was found in the motion of the traveling table.

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We propose tailor-made multilayer piezoelectric actuators (TAMPA) having large displacements and large forces. In existing piezoelectric actuators. production of small low-cost actuators having large displacements and large forces is difficult to achieve. We solved this problem by combining two bimorph-type piezoelectric elements with both ends simply supported, and stacking several elements on top of each other. Moreover, TAMPA is a tailor-made actuator whose displacement to force ratio can be varied widely by adjusting the size of the bimorph-type piezoelectric elements even when the total size of the actuator is kept constant. In this study, the bimorph-type piezoelectric element was analyzed, and the relationship between the displacement and the force under fixed conditions was experimentally determined. The relationship between the displacement and the force of TAMPA was theoretically derived. The analytical results showed that a TAMPA having dimensions of approximately 10×10×10 mm is capable of generating displacements of several hundred μm or the force of several N. A prototype was produced and its performance was evaluated. These results agreed well with the analytical results, confirming the validity of the analytical results. Finally, because the lead in PZT can cause environmental problems. a TAMPA was produced that used (K, Na) (Nb, Ta) O₃ piezoelectric ceramics instead of lead.

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Power-assist system (PAS) technology and its applications to manufacturing systems have attracted special interest recently. In such a man-machine system as PAS, the abnormality detection of the controlled mechanical part of the system, e.g., the collision detection of mechanical part, is extremely important. Some conventional studies have already proposed the collision detection methods for robots or PASs. In this study, we assume that DC servomotors are utilized as actuators. Then, this study proposes a novel power-assist controller design method. This method includes a software-based abnormality detection based on the current dynamics of motor. The controller design utilizes a two-degree-of-freedom control system structure which consists of an on-line linear simulator taking account of the current dynamics, an impedance controller and an LQI servo controller. The abnormality detection is realized by detecting the difference between the simulator's current and the real current of motor. The effectiveness of the method is verified experimentally.

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Radiation cluster control is proposed for the purpose of attenuating harmonic sound radiation into a free field using error signals derived from structural vibration sensors. The approach falls into a category of MAC (middle authority control) between used LAC (low authority control : structural modal control) and HAC (high authority control : radiation modal control), possessing the benefit of practicality of LAC, while providing high control performance as well as flexibility of control gain assignment similar to HAC. The structure of radiation cluster control system is outlined, showing that it is possible to control a target cluster without affecting the other clusters. A design procedure for the radiation cluster control system is proposed.

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This paper is concerned with active control of generating a virtual sound image at the designated spot in a free space while producing a zone of quiet in the same free space. The former strategy termed acoustic control and the latter called active noise control seem to contradict, however it is found they are able to coexist without conflict in the same free space of interest. With a view to minimizing a local acoustic power in the desired region, an optimal control law is derived under the constraint such that a desired sound pressure is generated at a target control point. Acoustic potential energy evaluated in the target zone is numerically analyzed, showing a significant attenuation especially at low frequencies may be obtained. Sound pressure over the target space is also numerically analyzed, revealing the noticeable reduction in the zone of quiet is generated, while the desired sound pressure at the control point remains intact. Finally, an experiment using an inverse filtering and filtered-x LMS algorithm is conducted, demonstrating the generation of a quiet zone at the designated region while maintaining the desired sound pressure at the control point.

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The purpose of this study is to solve the noise level caused by the transformer and reactor covered by the double covers, and to reduce the noise increased by the resonance of the wall. To research the phenomenon of the sound in the box, firstly, we simulated the vibration coupled noise analysis of a reactor, its double covers, and their air gaps by the finite element analysis. The simulation results shows that the noise of the air gap between the reactor and the wall to cover the reactor (cover 1), is increased by its resonant. For attenuation of this noise increase, we changed the size of the cover 1's height, and we attached the absorption materials inside of the cover 1's top. And we confirmed these noise attenuation effects. Secondly, we made a small scale model of the reactor with a shaker, and simulate the noise by experiments. This model was designed that the ratio of sound wave length of air gaps and the bending wave length of covers are same. The model measurement data of noise distribution was almost same as the simulation results. And we confirmed that noise attenuation effects for the absorption panel attachment inside of the cover 1's top. In addition to that inside attenuation of cover1, we had to increase the transmission loss of the top of cover1 for the resonant sound increase of the absorption panel back air layer. Both the attenuation levels of the double covers effect by this measure of the simulation and the small size model experiment, showed good agreements.

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The response of a structure subjected to diffused sound field excitation at high frequencies can be predicted by Statistical Energy Analysis (SEA), in which the mean energy level of the structure can be obtained. In addition to the mean energy level, the variance of the response is necessary in order to predict the tolerance limit of the response for a conservative design purpose. The theoretical variance prediction model for the case of the diffuse sound field excitation has been developed based on the assumption that the diffused sound field excitation can be regarded as a uniformly distributed point force excitation (rain-on-the-roof excitation). This model yields the ensemble variance of the vibration response taken over the structures with random parameters. In this paper, the group of plate structures with random natural frequencies is generated by Gaussian random Young's moduli of the plates, of which responses are numerically calculated by modal analyses for diffused sound field excitation and rain-on-the-roof excitation. The ensemble variances of the response to these two excitations are compared to the variance value predicted by the theoretical model. The result from the comparison shows good agreement between the prediction method and the numerical results, and the applicability of the prediction method to diffuse sound field excitation case is also discussed.

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Severe vibroacoustic random vibration is easily induced to satellite structure during the flight. Design specification of acoustically induced random vibration for satellite and equipment component is based on the acceleration power spectral density (PSD) at the mount interface. Ground acoustic test is conducted to verify the structural design and abnormal function of equipments. The response of a satellite structure under acoustic test can be predicted by Statistical Energy Analysis. In addition to the mean energy vibration level obtained by SEA, upper tolerance limit of vibration response in PSD needs to be predicted for conservative design purposes. This paper deals with the upper tolerance limit of PSD acceleration level of a satellite plate under high frequency diffused acoustic excitation. The upper tolerance limit is derived based on the statistical distribution of the vibroacoustic response together with the theoretical description of response variance. The upper tolerance limit for the acceleration PSD level obtained by Statistical Energy Analysis is compared with the experiment result. The result from the comparison shows that the upper tolerance limit presented in this paper yields good estimate of PSD upper tolerance level for conservative design. The effect of PSD estimation error in experiment on variance is also discussed.

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This paper proposes a basic method for constructing a formation flight based on Hill's equations of motion. It proposes a trajectory design of minimum fuel consumption for spacecraft relative position change by two impulses. Focusing on enlarging the formation size, we consider a problem to obtain the time and the phase of the second impulse when the phase of the first impulse is given. First, the phase of the second impulse is obtained as a function of the time of the second impulse. Then, the time of the second impulse is obtained to minimize the total fuel consumption. There are three ways to give two impulses for the minimum fuel consumption, which depends on the phase of the first impulse. Numerical studies of enlarging the formation size by two impulses are executed in order to verify the trajectory design.

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Trajectory planning of a spacecraft in formation flying is considered in this paper. Based on the equations of motion of the spacecraft that incorporate effects of J₂ geopotential disturbance, time-periodic realtive equations of motion are derived. Using the Floquet theorem to periodic terms due to J₂ disturbance, approximate solutions for eigenvalues and eigenvectors of the state transition matrix of the linearized equations are obtained by perturbation calculation and characteristics of relative motion are discussed. A correction term of an initial velocity of formation flying to suppress the effects of J₂ disturbance is obtained based on the approximate solutions. Numerical studies are conducted to verify the proposed trajectory planning.

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In this paper, we relate the golfer's cock and roll motions in the golf driver swing and eight club head and/or ball motions (head velocity, ball velocity, upper angle, side angle, back spin, side spin, carry and traverse) by experiment and statistical method. First, to be measured cock and roll motion variables, we used the three dimensional gyro sensor that we developed. Second, by using measured cock and roll motion variables, we classified with three groups by cluster analysis. By the multiple regression analysis method, the relation between selected 3 variables and eight club head and/or ball motions was estimated. As result of giving official approval accuracy of estimated regression equation with Adjusted R-square and analysis of variance, the equation of head velocity, ball velocity and carry had the significance. Finally, we extracted the cock and roll motions that affected head velocity, ball velocity and carry. From the sensitivity analysis, we found that the most important factors in improving the three motions are (1) angular velocity of roll is slower, (2) angle of cock is smaller, (3) when cock angle arised in driver swing, angular velocity of cock is faster.

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In this paper, we consider the problem of lens distortion adjustment of semiconductor lithography equipment. The objective of adjustment is to minimize the maximum absolute value of distortion. Formerly, an approximate solution method based on the least-squares method has been used. Recently, an approximate solution method based on iterative least-squares method with weight was proposed. However, calculation of that method often takes long time and a better calculation method has been desired. In this paper, we propose an exact solution method based on LP (Linear Programming) to minimize the maximum absolute value of distortion. Now, LP solvers find an optimal solution very fast owing to the progress in linear programming research. Consequently, optimal solutions for 20 instances obtained by our method provided adjustment parameter settings about 29% from 27% better than that by the solution method based on the least-squares method.

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In Hot Wire (HW) cutting of the Polystyrene Foam (PF), one of the rapid prototyping methods, usually tool path must be offset to outside of the profile of final shape larger than the radius of wire. The aim of this process is to avoid over ablation induced by tremendous heat effect, because this effect heavily affects on the accuracy of the final shape and surface finish. Therefore it can be easily understood that to clarify the fundamental mechanism of the forming process based on physical or chemical considerations and to know the amount of removal rate in advance are very important for the precision of the machining system. However, there is little study which discusses this point. Therefore, authors tried to make clear the basic behavior of PF in the HW cutting process by experimental work, and found that the natural convection have an important role. Furthermore, as the first step to estimate the amount of removal rate theoretically, numerical calculations with simple thermal conduction model were carried out. From comparison of the experimental and theoretical results, it can be concluded that in spite of the simple theoretical model, calculated removal width was coincided with the results obtained from experiments. As a result, possibility of the calculation to estimate the appropriate offset value in the hot wire machining was confirmed.

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This paper represents a mixed lubrication analysis for the interface between the Wave Generator (WG) outside surface and the Flexspline (FS) inside surface in Strain Wave Gearing (SWG). The analytical model consists of the FEM model of the WG outer race and FS and the mixed lubrication model combined with the pressure-compliance equation of surface roughness contact developed by Greenwood and Williamson and the average Reynolds equation by Patir and Cheng. The lubricant film thickness, the hydrodynamic and asperity contact pressures and the lubricant flow vectors at the WG/FS interface are calculated as a function of the input rotational speed. The numerical results show that in the present operating conditions the SWG works primarily in the regime of mixed lubrication and the roughness contacts are made at both edges of the WG outside surface. In addition, axial lubricant flow from the inside to the outside at WG/FS interface is found at the relatively low rotational speed of the WG.

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This paper describes the development of a process for end milling of aluminum alloy, using electrolyzed reduced water of dilute sodium chloride solution instead of the dry cutting. Dry process cutting is applied to the process of precision instruments where great surface cleanliness is essential. However, when using dry process cutting, it comes into question how to prevent the cutting temperature from rising, and the tool from wearing promptly. There is every possibility that electrolyzed reduced water is adaptable to the processing of the precision instrument, because it does not contain oils and fats, and excels in the cooling operation. First, we experimented in dry cutting, cutting using electrolyzed reduced water or cutting fluid. Next, we evaluated the cut surface cleanliness, surface roughness of cutting surface, the cutting temperature, and the tool wear. By this study, the following matters became clear. (1) The cutting surface layer which is done with electrolyzed reduced water is clearer than the one which is done by dry process cutting surface. And passivity layer was formed on the cutting surface which is done with electrolyzed reduced water. (2) If using electrolyzed reduced water, we can prevent the tool point of a blade from agglutinating. (3) The cutting temperature which is caused by the cutting using electrolyzed reduced water is low. (4) When the material is small, the surface roughness value of the cut surface which is done with electrolyzed reduced water is bigger than the one which is done by dry process cutting.

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Recently, stainless steel and titanium are mainly used as a structure material. And some surface treatments regarding coloring for these metals are used for producing high quality industrial product. In previous study, we have proposed that coloring for stainless steel and titanium using YVO₄ laser became possible, and the desired colors could be made by the inverse analysis using neural network. In this paper, controlling regarding coloring of the sensitive color and improvement regarding life of color were investigated to achieve high quality treatment. The ON/OFF regarding irradiation of a laser was decided by two steps data using both white and black on the conventional coloring. Sensitive color could not be made by this method because of large energy gap between each irradiation for very sensitive coloring. Therefore, we used intermediate data for controlling the ON/OFF regarding irradiation of the laser. The optimum data was made by the gray colors with the optimum level which were divided equally from white (=0 bit) to black (=256 bit). Then, improvement regarding life of color was experimented by some samples with the differ pitch of irradiation. It is concluded from the results that (1) New coloring method was effective for controlling regarding coloring of the sensitive color, (2) Coloring with fine pitch of irradiation on the stainless steel could improve regarding erosion.

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Five kinds of hard-brittle materials are tested by nano plastic forming method using an edge type tool, and the critical depths of these hard-brittle materials are studied. A new theory, where fracture mechanics is applied, is developed to explain ductile/brittle transition of hard-brittle materials. Numerical technique is applied to the theory, and it is found that the critical depth depends on K_IC/σ³₀. The experimental results are studied based on the theory. Single crystal silicon shows different characteristics from the glassy materials. Effects of material properties, such as initial defects in the material and crystalline anisotropy, on the critical depth are discussed.

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When the paper is incinerated under the multi oxygen environment : state of the oxidation, cellulose fiber with paper does the combustion as carbon dioxide also under the low degree temperature. On the other hand, when the paper is resolved under the small oxygen environment : state of reduction, cellulose is carbonized. The pyrolysis residue, as for tar, the china clay and Talc, etc. are changed the crystal grain and came to be also different compose chemically with the raw material. Then, authors have been studying the optimum carbonization method of cellulose and the use of the products. In this report, we deal with the result of using the pyrolysis residue to purify the waste fluid.

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The authors have developed two types of metal jet nozzles, i.e., a molten metal type and an electric-discharge type. In the molten metal type, the molten metal droplets are jetted through a hole in the nozzle by the action of a piezo-electric actuator. In the first half of this paper, the jetting mechanisms of metal droplets and the minimum droplet sizes able to be jetted are discussed. Some considerations show that an ultra-small droplet can be jetted in the case of the molten metal having a concave meniscus to nozzle material. On the other hand, it becomes very difficult to jet smaller droplets in the case of molten metal having a convex meniscus. These discussions are confirmed by experiments under several combinations between molten metals and nozzle materials. In the electric-discharge type, molten metal droplets are jetted intermittently by blowing out the molten balls which are formed at the end of a metal wire by the electric discharge. The mechanisms of the droplet formation are discussed. On the bases of the discussion and the experimental results, the minimum and maximum droplet sizes are then estimated under practical conditions.

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In this paper we propose Favored Feature based Design Support System (FFbDS). The system helps a user to evoke implicit perspectives and view points for designing and to put them into shape. This system works through an interaction between the user and a computer system. The user evaluates design samples generated by the system and the system estimate favored features to which a user pays more attention. User selects an estimated favored feature and the system generates design samples based on selected feature. A user can notice own preference by demonstrating favored features which the user had not noticed. This function helps user to externalize his/her implicit preference and to expand his/her perspective and point of view. Operation of this system is easy compare to existing design system in which user has to adjust design parameters by him/herself (a manual design system) so that a customer as non-designer can use it to put his/her image of required styling into shape. This system was compared with a manual design system and effectiveness of the system is demonstrated by design experiment with 3D cylinder model consisting of superquadratic ellipse cross sections.

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