Experimental studies have been conducted on the hydroelastic unstable vibration of a thin cylindrical weir. A test cylindrical weir made of polyester with radius R=100mm, length L=113mm, thickness h=0.244mm, and water was used in the experiment. In this paper, characteristics of the unstable vibation of the flexible weir due to a liquid flowing over it are presented. It was found that the vibration mode of the flexible weir varies with the volume of the liquid flow as well as with the height of the inner liquid inside the weir. This result may provide useful data for the theoretical investigation of this kind of unstable vibration.

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Liquid motion in partially filled rectangular and circular cylindrical tanks, in response to pitching excitation, is investigated. The nonlinear ordinary differential equations governing the liquid surface oscillation are derived. It is shown that the distance between the pitching axis and the liquid height at rest affects the liquid sloshing. The condition of excitation for the liquid surface to remain planar is obtained. The time histories of the liquid surface displacement are calculated to the harmonic pitching excitations. An experiment was conducted using model tanks. A good agreement was found between the theoretical and experimental results.

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This paper presents an analysis of the vehicle-passenger dynamic interaction on a highway bridge with misalignment. Vehicle, occupant and highway bridge are treated as a coupled vibration model. Six suspected misalignment patterns caused by earthquake or aging are treated. Surface roughness of road and misalignment are the main factors which seriously influence ride comfort. Influence of these factors on ride comfort have been analyzed, and it has been determined that they seriously influence ride comfort. The correlation between acceleration and dimensionless misalignment value is presented in the form of parametric plots, tables and recommended polynomial formulas. The random roughness of real highway surface has also been taken into account in this paper.

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This paper presents a method for obtaining vibration response of a viscoelastic spiral rod having straight portions on viscoelastic supports. The expressions for calculating frequency response are obtained by means of the transfer matrix method, in which the exact solution of the differential equations with twelve state variables for the static deflection is applied. Inertia forces and rotatory inertia are included by making use of the point transfer matrix, and the bent portions are also considered by including the transfer matrix of coordinates. Numerical calculations were carried out for the rod with both an elastic portion and a viscoelastic portion carrying a mass at the end. In this problem, the rotary vibration is of importance because it generates noise, hence the location of the viscoelastic support which induces the rotary vibration of the mass minimum is discussed in detail. The fuzzy algorithm by which the optimal location of the supports is obtained is also presented.

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The effect of a dynamic damper on the self-excited vibration of a rotor system induced by joint friction is investigated both theoretically and experimentally. The system is such that two flexibly supported rigid shafts are connected by two Kardan joints and one cross-groove (CG) joint and loaded, and a dynamic damper is attached to the center bearing. The Coulomb friction in the CG joint mainly induces the self-excited vibration. As a result of investigation, it is found that the dynamic damper has a stabilizing effect on the self-excited vibration and expands the stable region for the system with the initial intersecting angle. The damper suppresses the vibration amplitude in the unstable region independent of the initial intersecting angle.

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Research and development of a new type of high-damping rubber damper for high-rise buildings/structures to mitigate earthquake or wind-induced structural response is described in this paper. Tall buildings/structures can undergo excessive structural deflexions, at their resonant frequencies, due to excitation from strong earthquake motion or wind effects. Also, for weak earthquakes, which occur several times a year in Japan, or for weak wind, it is considered that the structural aseismic comfort will be strongly needed in the near future. The high-damping rubber damper developed in this study dissipates energy sufficiently, and the responses of the building are significantly reduced.

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This paper presents numerical simulations for balancing a rigid rotor. The influence coefficient and least squares balancing methods are compared, under the assumption that the initial vibration values used to calculate correction masses contain errors. The errors in the initial vibration values are : ( 1 ) errors in amplitude, ( 2 ) errors in phase angle, ( 3 ) errors in both amplitude and phase angle. In the three cases, errors are given in initial vibration at one measuring position. A number of numerical simulations are carried out and a comparison is made between correction masses and residual vibration values obtained by the two balancing methods. The results show that the vibration amplitude obtained with the least squares method is smaller than that obtained with the influence coefficient method.

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This paper presents a three-dimensional dynamic modeling of the upper part of a passenger's body, carried out using a three-mass system for the head, chest and hip. The equations of motions for the system are formulated using the Lagrange method. A dynamic excitation apparatus for the human body was manufactured, and experiments on the human body have been conducted for three exciting directions, the frontal, the transverse, and the vertical. Joint parameters, such as damping and spring constants of the neck, abdomen, and lower-hip portion are identified using the multistage method of the partial optimization technique with a least squares approach, for minimizing the discrepancy between the theoretical and excitation test results. It is shown through the comparison of calcurated results with those of experimental results that the motion of a human upper body under sinusoidal excitations can be easily analysed using this approach.

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A few studies have been reported on the transient vibration of clamped beams impulsed by a spherical impactor. The governing equation of the transient vibration becomes a nonlinear equation due to the contact force between the beam and impactor, and due to the axial force caused by bending of the beam. Although effects of contact force and axial force on the transient vibration of the beam have been studied independently in some reports, one can find no reports discussing both effects. In the present study, it is assumed that the contact force can be estimated by the Hertzian force-deformation relationship. A numerical approach has been proposed for taking into account effects of both contact force and axial force. With the comparison of numerical results and experimental ones, it follows that one can estimate accurately the deflection of the beam and the axial force caused by bending using the proposed approach. From numerical results, furthermore, it has been made clear that one cannot neglect the effect of the axial force caused by bending on the deflection in the case of the clamped thin beam.

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The steady-state response of damped cylindrical anisotropy disks made of fiber-reinforced plastic and rotating at a constant angular velocity, subjected to external harmonic force at a point fixed in space, was analyzed. The distribution of the internal stress was obtained analytically from the equilibrium equation of radial force, which was expressed by the space coordinate. The equation of motion of the rotating cylindrical anisotropy disk, with the internal damping expressed by the complex Young's modulus, was derived by use of Galerkin's method. The driving-point impedance and the mode shape have been calculated numerically.

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A computational method for identification of corrosion profile arising in thermographic inspections is presented. Thermographical data from the front surface are used in the estimation of corrosion profile on the back surface. The depth information of corrosion profile is characterized by the unknown coefficient vector of B-spline functions. The approach investigated in this paper is a parameter estimation technique for a thermal diffusion system with external boundary input. An idea related to the “method of mappings” is applied to the determination of the shape of the back surface of a plate. The forward problem is then discretized based on a finite Galerkin method. Tikhonov regularization is used to stabilize the resulting output least-square problems. A computational algorithm is proposed using the trust region algorithm. Computational experiments are performed which demonstrate the applicability and feasibility of the proposed algorithm.

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This paper presents a method for estimating the shape of flexible structures from multipoint spatially distributed measurements of structural deflections. The estimation algorithm is based on an infinite-dimensional approach, where the estimation errors are reduced by introducing the necessary finite element truncation and approximation after solving the estimation problem for the distributed parameter system. This paper also proposes a remote optical sensing system for fast and precise measurements of multipoint structural deflections. The optical measurement system consists of a laser slit scanner and corner-cube reflectors distributed on the flexible structure. An experimental measurement system has been implemented for one-dimensional deflection estimation and tested on a simple structure in the laboratory. The results of the numerical simulations and experiments show the practical usefulness of the proposed shape estimation method.

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Howling is one of the most important problems to be solved in active noise control. The authors have shown that a 2-microphone system utilizing the time delay corresponding to the distance between the two microphones should have an acoustical condition wherein no reflection wave should exist from the opposite side to the targeted opening end. In this paper, another solution called 2-microphone transfer function ratio system is introduced to eliminate the signal from the secondary source. An echo canceller technique is also studied in this paper. The signal convoluted by the transfer function from the secondary source to the detection microphone is subtracted from the detection microphone signal. The acoustical condition is studied theoretically, taking into consideration the reflection wave from both sides. The effect of eliminating the signal from the secondary source was confirmed by the experiment. The coherence function between the source signal and the howling canceller output was measured. The correlation was recovered by using these systems.

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Experimental study of gyratory sifters, which are used to remove aggregate or alien substances, is presented. The effects of operating conditions, such as the bed depth of powder, the sieve revolving speed, and the size and shape of the sieve, on sifting capacity or sifting rate are investigated. The motion of the powder bed on a screening surface is also observed. Experimental results show that the sifting rate is very sensitive to the bed depth. There is an optimum bed depth at which the sifting rate is maximized. The sifting rate of a circular sieve is higher that of a rectangular sieve. The sifting capacity increases with the revolving speed.

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This paper deals with motion control of an inverted pendulum using neural networks (NN)based on optimal tracking control. First, we examined the control performance in the nonlinear region, applying the optimal tracking control theory to the inverted pendulum. Second, the control system in which the optical tracking control system was replaced with two NNs and a feedback (FB)was designed. In the nonlinear region, the NN control performance was compared with optimal tracking control from the points of view of simulation and experiment. As a result, it was shown that NN control is valid for nonlinear problems in the case where the pendulum angle is large and the motor is saturated.

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This study shows that the stabilizing and positioning control of a flexible inverted pendulum of which the pivot is mounted on a cart is experimentally possible by means of H^∞ control theory. Since the control system has an eigenvalue of zero, the design method of H^∞ control utilizing a settling function is applied, and one controller is designed with consideration of the rigid and the flexible first modes and another is designed neglecting all flexible modes. By numerical calculations and experiments, we have investigated the positioning control characteristics and the robust stability against disturbance to the pendulum of each controller, and it has been made clear that the robust stability of the controller designed considering the flexible first mode is superior to the one designed neglecting all flexible modes.

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This paper is concerned with the design of a Model Reference Adaptive Control System (MRACS) for motion with unknown nonlinear frictions. From the control system viewpoint, the static friction and Coulomb friction are characterized by a nonlinear deadzone element and constant disturbance for the control input signal, respectively. Then, the MRACS for the nonlinear frictions is considered for a nonlinear system which is a cascade combination of an unknown deadzone block or disturbance and a linear dynamic block. In order to verify the validity of the theoretical results, the design method described above is applied to a servo system influenced by friction. Experimental results show the high performance of the constructed MRACS and the effectiveness of the proposed method.

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In pneumatic servo systems, it is difficult to achieve high positioning accuracy using PID or optimal control methods, because the change in load mass and air compressibility causes parameter variation of the plant. In this paper, to enhance the positioning accuracy of pneumatic servo systems, we propose design scheme of the adaptive pole-placement control system. This plant consists of a pneumatic cylinder which is sealed by labyrinth packing, supported by air bearings and driven by two electro-pneumatic proportional valves. The Coulomb friction of the cylinder is negligible. Therefore, we consider only the influence of static friction. The feature of this design scheme is that an approximate integral compensator is introduced in order to eliminate the influence of constant disturbance caused by static friction

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Presently, tracking control with high speed and high accuracy is required in the fields of robotics and machine tools. For the control problem, we proposed a preview control system which has a superficial evaluation term in its performance index. In this paper, we consider the physical meaning of the term for application to the problem. As a result, it becomes obvious that two cases are important. The first one is when tracking position is on the velocity vector of the desired signal. The second one is when the desired signal does not change. In both cases, the term becomes zero ; then the path error becomes large. To improve the problem caused by the first case, we introduce an auxiliary superficial term into the performance index of the preview control system. The synthesis of the new path control system is presented. To evaluate the effectiveness of the proposed control system, simulation studies are carried out. The simulation results show that path tracking ability is markedly improved.

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With the aim of reducing “booming noise”, which is one of the major noise problems for 4-cylinder-engine vehicles, a basic study on active noise control (ANC) has been carried out. First, the interior sound field was examined in terms of its fluctuation characteristics, which eventually led to the confirmation that an adaptive technique is necessary. The multiple-error filtered-x LMS (MEFX) algorithm was then found to be effective through an “off-line” shaker test on a real car. Secondly, the acoustic intensity method was applied to analysis of the sound field inside a car. Actuator (speaker) positioning was considered based on this analysis of standing wave and traveling wave contribution. In addition, the controller parameters' influence on control performance was estimated by means of computer simulation. Guidelines were developed for applying this technique to automobiles. ANC was found to be capable of reducing booming noise by more than l0 dB.

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In the case of applying shape memory alloy (SMA) to an actuator, the greatest problem is its nonlinear behavior. It is also known that this characteristic of SMA significantly depends on working conditions and environment. Consequently, development of a mathematical model of the SMA actuator is remarkably difficult. In this study, a method is investigated for realizing position control of the SMA actuator using fuzzy reasoning. In this reasoning, qualitative representation that is based on the rule of linguistic variables is easy to make. As a result, the identification of a mathematical model for control of the system becomes unnecessary. In this paper fuzzy reasoning is applied to control of the SMA actuator, and its applicability is confirmed through experiments.

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This paper describes a new technology on image recognition of objects using fuzzy theory. The standard method of pattern recognition is geometrical pattern matching. This is accomplished by comparing an object with a standard pattern, which is effective in cases having little ambiguity, such as industrial products. However, it is generally difficult to recognize natural products, because these objects have essential fuzziness caused by the differences is shapes, sizes and colors. In this paper, pictorial pattern recognition including these kinds of fuzziness is investigated, and a new image recognition system is proposed with the application of fuzzy theory. Through discrimination experiments made for ten categories such as apples, bannas, lemonns and others, satisfactory results are obtained. At result, it is certified that the pattern recognition proposed here is more effective to recognition of resemble objects categories.

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Trajectory tracking control problems are described for a two-link robot manipulator with artificial rubber muscle actuators. Under the assumption that the so-called independent joint control is applied to the control system, the dynamic model for each link is identified as a linear second-order system with time lag by the step response. Tow control laws, the computed torque and optimal servo control methods, are designed and experimentally applied to the actual robot manipulator. The effectiveness of the proposed control method for the robot manipulator is illustrated through simulations and experiments.

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Fields of robot application progress from line production, such as car and electronics assembly, to facility maintenance such as inspection and repair, which is not automated at present. Intelligent functional elements, environmental information, task planning and operational programs (data bases), are necessary so that an intelligent robot may be used for new applications. It is also important that such a robot be easily portable. The authors propose an integrated robot system, typically combining end effectors, a multi-use manipulator, lifting equipment and open-system communication (connectable to various CPUs : Center Processing Units). Essential functions and operational perfomance are experimentally verified by a prototype system consisting of automatic end effectors, a 7-axis intelligent manipulator, and digital signal transmission (LAN : Local Area Network) between servo-controllers and drivers that makes motion control parts compact enough to be mounted on the actual robot.

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This paper deals with practical simultaneous control of a manipulator and an antenna mounted on a free-flying robot in space. An extended generalized Jacobian matrix and resolved motion rate control are used to establish the control method for antenna positioning and the capture of a target by the manipulator. Moreover, a method revising the angular velocity references to the robot system is introduced to improve the control performances. Computer simulation in which a robot system having a base, 2-DOF manipulator, and one link antenna is used suggest that the proposed method is useful and practical.

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This paper deals with the effectiveness of a neural network controller implemented in a control system of an underwater robot manipulator when the robot performs the task of catching and gasping an object floating in water. The neural network must learn the nonlinear behavior of the floating object generated by the fluid flow due to the motion of the robot arm when the robot rotates and extends its arm toward the object. The learnd neural network is implemented as a forward controller together with a feedback controller. Experiments showed a good performance in catching and grasping the floating object in water even when the object is moving away.

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Many grasping control methods for multifingered endeffector, such as the compliance control method or hybrid position/force control method, have been studied. There still remain some problems in the subtle control of finger motion as in human fingers. In this paper, we describe the grasping motion of a 3-fingered endeffector with each finger having 4 degrees of freedom. In order to derive the dynamics of the system, we formulated the equation of motion for 3 fingers grasping a stiff object with their tips. Then the neural network controller, which has a criterion function learning algorithm, is applied for the 3-fingered endeffector motion control. Simulation results show the effectiveness of this control method for grasping, and finger motion is characterized by a properly designed criterion function in the NN control.

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In the previous papers, the authors investigated a robot cat which could restore its attitude during free fall by twisting and controlling the body. Then the principle of the twisting motion was elucidated : the robot cat could rotate its body by 180 degrees' within 0. 6 seconds when released from an upside-down position. In this paper, 3D midair attitude detection and landing control of a newly developed robot with multiarticulated twin legs were studied. A postural detection method using the Euler angle caused by the 3D attitude angles detected by three rate gyrosensors mounted on the robot was proposed, and a landing control method for the twin legs using 4 pairs of antagonists composed of artificial rubber muscles was described. An experiment conducted with this robot shows that the attitude of the robot thrown in an arbitrary direction could be detected and the legs could be successfully controlled to turn towards the ground for landing.

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In this report, the method of active sensing is applied to assembly work of a self-organizing manipulator which we introduced in previous research. We placed a 6 axis force/torque sensor in the wrist of the manipulator and a CCD camera into the hand of another manipulator. With cooperation of hand and eye, haman beings can perform a variety of versatile tasks. The eyes guide the motion of the hand, while the hand moves to make the object more easily seen. We attempt to construct a system which works in the same way as a human being. In assembly work, many types of contact status of cells are analyzed. The scene simplification is based on the cooperative motion of the camera and manipulator. We integrate a vision system, a manipulator, and force/torque in to a hand-eye working system. The method of average visible rate is proposed to evaluate the viewpoint of thc camera. A strategy for planning the assembly work is presented for the cellular type of self-organizing manipulator system. The efficiency of the proposed system is shown by experiments.

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This paper deals with a primitive approach for the self-organized structure of the Cellular Robotic System. The Cellular Robotic System, which is named as "CEBOT", consists of a large number of autonomous robotic units called "cells". Since cellular robots are comprised at the connections of cells, self-organization is basically the most important issue. This paper presents the progress of self-organization of the cellular robots, in which the cells walk randomly. To organize the structure, these cells must recognize and communicate with each other. Based on the communication between cells, each cell makes a decision whether or not to connect to the other cell. We assume that each cell has the genetic information as a structural map of itself, like a biological cell. In this paper, we consider the swarm behavior of the cells from the point of view of "selfishness" and "altruism". Based on the simulation results, we will show the influence of some parameters such as "selfishness" and "altruism", sensing ability and directional intensity.

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In this study we develop a new hydrostatic air bearing slider with comb-shaped grooves which can provide high damping ratio in the high-frequency region of resonance, as well as high stffness. The basic idea to increase the air film damping at a high frequency region is to reduce the compressive effect of the air film by a set of parallel inner grooves. Increases in groove number and groove depth generally result in high damping in the high-frequency region, but excessive increases cause negative damping in the low-frequency region. The design procedure to determine the optimal value of the groove parameters is described by the design charts based on numerical calculation. The developed air slider has a high static stiffness of 418 N/μm (non-dimensional stiffness is 0.59) in the vertical direction, Damping ratios are 0.19, 0.12 and 0.07 at the natural frequencies of the roll, pitch and vertical vibration modes, respectively.

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The frictional characteristics of a porous bronze bearing are experimentally studied in hydrodynamic and mixed lubrication regimes. The results show that the relationships between the coefficient of friction μ and Sommerfeld number S obtained for a range of oil-feed pressure and shaft speed could be rearranged using dimensionless oil-feed pressure p_s. With decreasing S, μdecreases in the hydrodynamic regime and then steeply increases in the initial stage of the mixed regime. However, at lower values of S, μbecomes steady and its value remains almost the same for various p_s. The value of S at the transition point from the hydrodynamic regime to the mixed regime is significantly affected by p_s, becoming smaller for higher p_s. To estimate μ in the mixed regime, a simple frictional model is proposed on the basis of the observed results that the extent of the oil film in the bearing clearance in the mixed regime remains steady and nearly corresponds to that at the transition point. The calculated values for μ using the model are found to approximately agree with the experimental results.

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The purpose of this paper is to compare some schemes for the applicability to the gas-lubricated Reynolds equation in the high-bearing-number region. Weighted upstream schemes (the simple upstream, the exponential method, the stabilization method), polynomial approximation schemes (QUICK scheme, Kawamura-Kuwahara scheme, etc. ) and the exponential approximation method are taken up. Steady pressure distributions of slider bearings are calculated using these schemes. It has been clarified that polynomial approximation schemes are unstable and that the exponential approximation method and the stabilization method are the most precise.

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This paper presents a study on the load-bearing capacity of sintered metal gears. Test specimens (gears and rollers) made of partially and completely prealloyed steel powders were compacted to the densities of 6. 8∼7. 4g/cm³, sintered at 1403 and 1513K, and then case-hardened. The bending fatigue strength and the surface durability of these sintered metal gears were investigated by carrying out pulsator tests and running tests, respectively. The results were compared with the roller test results. The position of crack initiation and the kind of surface failure of sintered metal gears were examined. The load-bearing capacity of these sintered metal gears and the effects of alloying method, density and sintering temperature on the load-bearing capacity were determined to a considerable extent. Furthermore, the effect of shot-peening on the load-bearing capacity was also examined by carrying out bending fatigue and contact fatigue tests for shot-peened sintered metal gears and rollers.

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In the cutting process, chatter vibration occurring between workpiece and tool reduces accuracy and productivity. The dynamic characteristics of a machining operation system that has the structure of machine-tool-workpiece have a serious effect on chatter vibration. The dynamic characteristics of a system are generally estimated in a shock excitation test. However, the result is insufficient to account for the action of chatter vibration during the actual cutting process. The dynamic characteristics of a system during the actual cutting process must be clarified in order to understand the transient vibration mechanism of actual chatter vibration. This paper reports the existence and behavior of dynamic compliance characteristics during the turning process. It affects the occurrence of chatter vibration directly, and this characteristic has not yet been sufficiently examined.

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This paper introduces contour grinding of ceramics with an electroplated diamond microquill (wheel) of which the diameter is less than 1 mm. A contour grinding machine was developed for this experiment. The machine has an ultra-precision air spindle with a maximum revolution speed of 120 000 rpm, an XY slide table with AC servo motors for positioning of the workpiece, and a dynamometer unit for force-controlled machining. This machine, therefore, can be used for simultaneous two-axis linear or circular path contouring. In this paper, basic grinding characteristics were investigated in linear cutoff grinding of an aluminum nitride board. The main results obtained are as follows ; ( 1 ) The grinding force becomes smaller and the quill life becomes longer as the grit size of the diamond grain increases. ( 2 ) With increasing work speed, the total cutting length increases. ( 3 ) At a low work speed, the adoption of the workpiece oscillation which is perpendicular to the cutting direction has an effect on quill life.

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The maximum temperature at the interface of a spray coating and substrate has been investigated using a theory of heat conduction and measurement of a thermal cycle at the interface. The experiment of spraying Al₂O₃ powder onto steel showed that the maximum temperature did not reach the maximum value predicted from the theory. It is concluded that the cause of discrepancy is neither the distance between the interface and the point measured by a thermocouple, nor the dimension of heat flow used in the theory. It is shown that the experimental value of thermal cycle is explained by the theory which focuses on each particle of Al₂O₃ powder adhering to the substrate.

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A flexible and incremental sheet metal bulging machine using a few spherical rollers has been developed for the small-batch manufacture of nonsymmetrical shallow shells, and for eliminating the necessity of the forming die and punch. The hand-operated bulging machine performed a wide range of sheet metal shaping of complex shapes, for example, pyramidal shells, shells of the frustum of a pyramid, shallow pans and embossed panels. An approximate calculation method for the distribution of thickness strain and the maximum bulging height of the shell was proposed using the fracture limit from the incremental bulging test with a ball punch and a geometrical plane-strain deformation model. The predictions for the shell of the frustum of a quadrangular pyramid and the shell of the frustum of a right circular cone were in reasonably good agreement with experimental values for the annealed aluminum sheet.

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The bore-expanding process is performed on commercially pure aluminum (Al-0 and Al-1/4H), and 60/40 brass(Bs-0 and Bs-1/4H), and an aluminum alloy (A5182-0). Except for in the case of Al-1/4H, breakage (or the localized neck) starts at the rim of the bore and extends obliquely to the rim circumference. The issue of limiting strain for this case is raised to some extent when compared with that in uniaxial tension. We refer to this phenomenon as “strengthening due to constraint effect by surrounding material”. To verify this point, strain distributions along the radial line are measured to determine whether or not the steep negative gradient of hoop strain exists. The constraint effect is greater for a steeper gradient. As for Al-1/4H, breakage starts at the point 3 mm from the rim edge and extends along the radial line. The strain gradient around this point is almost 0 and thus little constraint effect exists. Moreover the state consists almost entirely of in-plane strain with no radial strain. This is why breakage starts at an inner point. It is emphasized that most breakage conditions derived thus far for a uniform field should be employed not at one point but over a range for breakage judgement, especially in the case where the localized neck extends along the direction of negative strain gradient. The effect of planar anistropy on the direction of the starting point of the breakage is discussed. It is also emphasized that appearance of the localized neck (localized-type instability)may precede diffuse-type instability in bore-expansion with a small-diameter bore, and that localized-type instability predominates to induce breakage. Finally, the critical bore diameter such that the punch penetrates through the sheet without breakage is discussed.

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A new forming process of continuous fiber-reinforced thermoplastics (FRTP) having high toughness and high strength is required for mass production and low cost. In this study, bulge forming of FRTP braided tubes by means of axial compression was carried out as a new technique of forming FRTP utilizing fiber orientation rearrangement. As a result, bulge forming was achieved without buckling when flow stress of the matrix was small enough to rearrange orientations of the braid. Kinematics of the braid was also considered, and that calculated from the model was compared with that from experiment. In addition, the kinematic state of the braid after deformation was simulated through calculation from the geometric braid model. It was found that the "normalized profile" of the bulged part does not change during the process, and the thickness of the matrix depends on fiber orientations in bulge forming.

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Advanced ceramics are becoming widely used today in mechanical components. However, it is quite difficult to machine these materials because of their high strength, hardness and brittleness. In order to increase the machining ability, high-pressure coolant is supplied to the cutting area from inside the cutting tool through a spindle. For this mechanism, a rotary union which transfers the coolant to the rotating spindle is required. So far, mechanical seal rotary unions have been applied. It is, however, considered to be difficult to apply the mechanical seal rotary unions under high-speed rotation due to the rapid wear of the seal. In this study, rotary unions which can be used under high-speed rotation are proposed as one of methods of improving the performance of machine tools. The performance of the developed rotary unions is theoretically and experimentally investigated.

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In this paper, we propose a method for estimating colors in order to evaluate the color combination in a factory by means of the color image processor technique. First, data of standard colors are determined from JIS standard color chart (1 680 colors), and represented numerically by Value and equations between Hue and Saturation under various light sources, and recorded in a reference data base. In each light source, the gray scale is measured to determine the position of achromatic color, that is, the orgin of color, and the brightness of the light source. Second, the unknown color is measured and represented numerically as Hue, Saturation and Value. The selected color is estimated from the two equations in which the point (X, Y) is interposed under the condition V.

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This paper proposes a concept of a design aid that constantly monitors the designers' modeling process. The design aid gives the designer appropriate information in terms of qualities such as reliability throughout the product modeling task. In order to realize the concept, it is necessary that the product modeling task and the model-applying tasks, which examine the qualities of the design object, are processed concurrently. To achieve concurrent processing, the authors present a method for real-time operation of model-applying tasks. In this method, the model-applying tasks are decomposed into subproblems, and these are solved bit by bit in parallel with the product modeling task. With this method, the designer is informed of malfunctions in the design object early in the product modeling task.

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In both cooperative design by many designers in various engineering domains and modification design which is considered cooperative work with origninal designers, communication among designers is essential. In order to communicate efficiently among designers, a form features to describe designers' intentions must be designated in the geometric model of a designed object. There are two methods of designating form features, denotation and connotation. The connotative method is more useful for describing the designers' intentions. In this paper, we propose a method of describing designers' intentions by means of connotative designation of form features by applying conditions to satisfy functional requirements. The developed CAD system based on the proposed method supports cooperative design and modification design by maintaining the designers' intention that is related to functions and form features in the progress of the design process. When the required functions cannot be satisfied by the modification, the system gives a warning for remodification.

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The coal chain shows the coal flow from the shipment wharf in the production region to the unloading wharf in the consumption area. This chain is expected to become of large scale and high speed. In this study, recommendations are presented for the optimum design for a materials handling-carrying system in a coaling wharf. In the first report of this study, a simulation analysis method was established to clarify the system behavior. Case study was performed by applying this analysis method to actual wharfs. The analysis was conducted for Qinhuandao Port and Shanghai Port of China which have a typical shipment wharf and unloading wharf, respectively. On both wharfs, present operation states were analyzed by simulation, and the results were examined in comparison with the obtained results. Consequently, it has been confirmed that the analysis results show good agreement with the obtained results on the queueing characteristics of ships and the fluctuation of coal storage quantity. Moreover, by simulation analysis, the effect of the ability change in the berth area on the duration of stay of ships in the wharf has been explicated. From this, it was investigated how the optimum handling ability of the berth area should be determined by the change in equipment and the fluctuation in handling amount.

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