In recent years, multi-agent architectures which have been studied in the field of artificial intelligence might attract a great deal of attention to the ability of the cooperative properties for engineering. In this study, we proposed a new approach to find the improved design in the layout design and shape design problems of framed structures by applying the multi-agent architectures. We considered each agent as an element in Finite Element Analysis and proposed modification rules for the layout shape of the structure. Following this approach, each agent proposes modification plans based on his or her evaluate function. The proposed plans are picked up or rejected by communication among agents and the remained plans may improve a design created from an initially simple structure. We developed the simulation system running on the UNIX and considerations have been given to the simple truss structural design and some advantages of the proposed have been shown and confirmed.

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The present paper deals with a free vibration analysis of the circular cylindrical shell partially filled with liquid. On the assumption that the shell is made of the double-ply laminated CFRP composite material and the liquid is incompressible and inviscid, the linear responses of the shell vibration are theoretically analyzed. Displacements of the shell wall vibrated under a clamped-free condition are expanded into a Fourier series for circumferential coordinates. The buldging in shell under the condition is simulated on the concept of the finite element method (FEM) using isoparametric elements. The equation of continuity and the linearized Bernoulli's theorem are applied to analyze the motion of liquid free surface. The natural frequencies of vibration are determined in relation with the ply-angles of laminates for given parameters. There are some differences in the trend of frequency curves between the (φ/φ) laminate and the (-φ/φ) one, where φ is ply-angle. In the ratio greater than 0.5 of liquid level to shell height, the frequencies of the cross-ply laminated shell increase first with increasing the angle φ and then show plateaus in the higher ply-angle regions over 60° of curves, while for the angle-ply laminated one they gradually decrease after reaching the maximum values. In the ratio less than 0.5, however, the both laminated shells show the maximum value in frequencies at a paticular ply-angle. When circumferential wave number or mode of vibration is considered as a parameter, for the both laminated composite materials the curve is the same as stated above.

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Structural vibration modal response analysis during lift off has been improved in the H I rocket development by considering its launch pad. The original analysis introduced through the technical assistance for the N-I and N-II development had ignored the launch pad. Consequently, the H-I rocket modal analysis has improved the procedure by taking into account of the boundary condition change between the rocket and its launch pad during vertical takeoff. This improvement includes the equations to connect the responses on fixed-free boundary conditions to those on free-free boundary conditions at the instant of lift Off. This paper covers:(1)structural vibration analysis techniques of the N-I, N-II, H-I and H-II rocket, (2)rocket vibration models by substructure modal synthesis method, (3)inherent improvement to introduce boundary condition change into modal response analysis at liftoff event, and (4)evaluation of above improvement by comparing an analysis with its flight data.

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Vibration tests using a large-scale piping model with teflon friction support were carried out to investigate a friction model and piping responses. The friction model in plane slip was described by modifying Coulomb's friction law and hypothesizing elastic deformation of a contacting plate. A seismic response analysis procedure of the piping system with friction was developed by an approximate modal analysis and confirmed to be adequate to evaluate the piping responses by coomparing simulated results and test results, and consequently, response reduction effect due to friction was evaluated.

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An analytical method based on vector fields is proposed for piecewise linear systems with singular regions or asymmetric restoring forces. By using matrix representation for these systems, state variables in each region can be explicitly expressed as a function of the time the orbit takes between two boundaries. The time can be determined by the Brent method, and periodic solutions can then be obtained. Furthermore, a new numerical technique to find explicit periodic solutions was developed, based on the Brent and Runge-Kutta-Gill methods. The validity of the proposed method is verified for three different 3-region systems by using the newly developed numerical method.

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In the operation of a tubular heat exchanger, or a gas heater, occurred acoustic vibrations, which could not be suppressed at all by installing baffle plates along the gas flow into the tube bundle of the gas heater. Baffle plates along the gas flow are always very effective in suppression of acoustic vibrations so far. To clarify the cause of the vibration phenomenon, we built a three-dimensional airflow scale model using the similarity method. Accordingly, violent vibrations took place, which have the same characteristic as the gas heater. We conclude that the model test method we conducted is useful to check the normal operation of a gas heater.

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We experienced unusual acoustic vibration in the operation of a tubular heat exchanger, or, a gas heater. This phenomenon is not one dimensional acoustic vibration in the direction perpendicular to the gas flow and tube axis. Experiment shows the vibration is in the direction of the gas flow. Therefore, it is very difficult to suppress by a conven.tional method after the onset of the vibration. So we have to confirm acoustic vibration characteristics. We performed scale model tests of a one-stage gas heater and checked some countermeasure methods which are effective.

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This paper describes optimum posture determination of variable geometry truss structures by optimality criteria method. A minimum compliance posture of variable geometry trusses for a given working load vector is realized by adjusting variable elements, where the adjusting control values are determined independently according to optimality criteria transformed from strain energy equation in advance. The validity of optimum posture determination by optimality criteria is confirmed numerically by applying it to the configuration control of a pair of variable geometry trusses containing ten adjustable elements for cooperative work.

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The damping mechanism in the new torsional damper proposed by authors, which improves the defects of knows dampers such as rubber dampers, oil dampers, solid frictional dampers and etc., is investigated experimentally and clarified as follows. (1) The damping effect depends on the relation between the inertia torque of damper mass due to torsional vibration and the friction torque due to centrifugal inertia force of crowds of solid balls, and isn't restricted by the natural frequency of shaft system and the loading torque on shaft system. (2) Torsional vibration is damped by not only the friction loss in coupling portion but also the fluctuation of natural frequency of shaft system. The latter is caused by angular sliding and coupling phenomenon of damper mass to damper case at every period of torsional vibration. (3) When the friction torque due to centrifugal inertia force of crowds of solid balls is nearly equal to that at the changing point from coupling to sliding of damper mass to damper case, this damper is powerful for damping the torsional vibration of shaft system.

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Since a commutator of the DC-motor is divided into a number of segments to have the torque in the circumference direction, the currents in the coils of the rotor vary and have alternative waves during the rotor rotation even in a constant input voltage. The currents become sharp waves, so that they have high frequency component. This implies that the rotor shaft and the case of motor are excited electromagnetic forces with high frequency components. Since high frequency noises are loud when they are input to human ears, so that when high frequency vibrations are suppressed, noises become small. From the situation, this paper discusses a method of noise reduction of Dc Motor. In the method, the current waves are controlled to be sinusoidal waves. The method and the control algorithm are given. In order to validate the method, experimental tests are carried out. It is proven that our method is applicable to the motor noise control.

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A numerical analysis is developed to the three-dimensional sound field in cylindrical duct with eccentric slit. A linearized unsteady Euler equation for acoustic disturbance is solved by a fourth-order accurate finite difference method. The boundary conditions at the curved rigid surface, such as the duct wall, are implemented properly for the linearized Euler equations. The three-dimensional structures of the sound fields are obtained for the several eccentricities of slit. The computed result shows that each eccentric slit has two different resonant frequencies, which are fully consistent with our previous experimental data.

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In this paper, dual dynamic absorbers are applied to the piping system in order to control the muItiple vibration modes. ANSYS, which is one of the software based on FEM, is used for the design of dual dynamic absorbers as well as for the determination of their optimum installing positions. The dual dynamic absorbers designed optimally for controlling the first three vibration modes perform just like a houde damper in higher frequency and have an effect on controlling higher modes. To use this advantage, three dual dynamic absorbers are installed in positions where they influence higher modes, and not only the first three modes of the piping system but also the extensive modes are controlled. Practical experimental study has also been carried out and it is shown that a dual dynamic absorber is suitable for controlling the vibration of the piping system.

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This paper deals with an application study of Magneto-Rheological(MR) fluid to a small size variable-damping mount for precision equipment of automobiles. MR fluid is known as a class of functional fluids with controllable yield stress of fluid by the applied magnetic field strength. A typical MR fluid is a suspension where pure iron particles of 1-20μm in diameter are dispersed in a liquid such as mineral oil or silicone oil, at the concentration of 20 40 vol%. A variable-damping mount filled with MR fluid was combined with a magnetic coil at the bottom, and its performance was investigated. Furthermore, a new strategy of control system for MR actuators was proposed, in which the cluster of particles in MR fluid under some magnetic field should be broken by the vibration energy so that the time constant might be shorter in the reaction process of MR fluid to the applied magnetic field. The control system was verified by the experimental investigations.

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This paper is concerned with a design method of multivariable linear controller based on frequency domain analysis and its application to an active vibration control for a carrier in warehouse. The method is based on the tuning of multivariable linear controller parameters by achieving partial model matching so as to minimize performance functions with respect to the relative model error between the loop transfer function matrix of the control system and the reference model. The proposed method is exanmined and evaluated by both simulation and experiment using pilot-scale carrier model in warehouse.

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The authors propose a self-powered active control system, which realizes active vibration control using energy regenerated by an energy regenerative damper and does not require external energy. In this paper, the self-powered active control is applied to the anti-rolling system for ships. The motor is required to act as an energy regenerative damper and an actuator, since the anti-rolling system is composed of one motor. The new control scheme that realizes the self-powered active control with a single motor is proposed. Through numerical simulations and experiments on a basic model, the performance of the proposed system is examined. The results indicate that the self-powered active control can be achieved in the anti-rolling system.

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This paper deals with modeling and control of a crane mounted on a tower-like flexible structure. A fast transfer of the load causes the sway of the load rope and the vibration of the flexible structure. Our object is to control both the sway and the vibration by the inherent capability of the tower crane. This paper makes its three-dimensional model for simulation and the reduced-order models in order to design the decentralized control system. Then, we design the decentralized H_∞ compensator for up-and-down and rotational directions. The simulation and experimental results verify the efficiency of the designed control system.

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Recently, development of a controller design technique for nonlinear system is required to improve the control performance. Sliding mode control technique is of considerable interest due to its capability to deal with nonlinear system easily. But the design technique for nonlinear system is not established. In this study, the design technique of sliding mode controller for nonlinear and unstable system is investigated using a inverted pendulum system as an example. A simple controller executing both swing-up and stabilization of inverted pendulum is developed using the nonlinear model, to which the sliding mode control technique is applied. Especially, the nonlinear hyper-plane is derived from the energy balance. In addition, a nonlinear model observer is designed to estimate the velocity of the cart and the angular velocity of the pendulum from these displacements. Then, the performance of the developed controller and observer is confirmed by numerical simulations and experiments. And, it is found out that the chatter of the control input is suppressed using the same precise nonlinear model in the controller and the observer.

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The tracking control accuracy of shape memory alloy (SMA) actuator is limited due to inherent hysteresis nonlinearity. It has been said that a push-pull type mechanism and the insertion of a resistance feedback loop are usefuI to effects of the hysteresis. This paper presents a position control system for compensating the hysteresis without such constraints. It is composed of feedforward loop and PID feedback loop. In the feedforward loop, the desired input corresponding to the desired displacement is obtained from a model of hysteresis. The proposed control system is applied to a bias spring type SMA actuator that is more difficult to be controlled accurately than a push-pull type one. Experimental results show that tracking control performance is greatly improved.

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In this paper, longitudinal control for a platoon as one dynamic system is proposed and evaluated. Difficulty of treating a platoon as one dynamic system is due to non linearity and uncertainty included in the characteristics of tractive and brake forces. A robust model-matching controller is developed for solving the above problem. The characteristics of the tractive and brake forces are equivalent to those of a specific transfer function by the model-matching controller. A longitudinal controller for platooning is designed with assumption that the model-matching controller works on each constituent of the platoon. Velocity of the leading vehicle and each spaces between the constituents can be controlled independently and smoothly by the longitudinal controller. The proposed control system is suitable for changing space as well as fixing space, and has potential to make the platoon execute intelligent tasks according to the various kinds of situations.

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This paper presents control system design for plasma containment in Tokamak fusion reactors. A mathematical plant model of plasma motion dynamics is derived by considering circuit dynamics of the control coils and eddy current models. So as to design a low order controller with numerical reliability, we have applied two approximation methods, singular perturbation and truncation, to the original plant model. The stabilizing controller is designed for the approximated plant model by standard H_∞ control method to achieve the robustness against disturbances and low voltage control. It is shown in simulation study that the designed reduced order controller works well for the original plant model and satisfies low control writage of the coils.

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In a pulverized coal fired boiler, various kinds of coals are used as a fuel. It is important to estimate properties of fired coal at the on-line, in order to realize good operated performance just like oil or gas fired boiler. Hardgrove grindability index is one of the important properties. Neural network method is proposed to estimate the index. Experimental results show that our estimation model is effective on the pulverizer, and is superior to multiple regression analysis. Study on the appropriate network structures is also described.

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The pneumatic servo-system has non-linear elements such as compressibility of air, friction between cylinder and piston. The control scheme with fuzzy inference is effective for such non-linear plant. However, the conventional fuzzy control has troubles in the shortage of adaptability and learning ability. Moreover, it seems difficult to attain the satisfactory control performance only by using the qualitative information of the plant. In this paper, we propose the new control scheme with fuzzy inference. In the proposed method, we compose the controller with the linear approximate model of the plant, which is one of the available information of the plant. In addition, the unknown controller parameters are identified by the fuzzy identifier and the shape of the membership function is automatically tuned to consider the effect of non-linearity. The effectiveness of the proposed scheme is confirmed by experiments using the existent pneumatic servo-system.

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In this paper, we propose a device for cooperation of multiple autonomous mobile robots. A device which enables local comnaunication, called "Intelligent Data Carrier (IDC)" is proposed. In this paper, we propose an algorithm to improve efficiency of iterative transportation tasks by autonomous mobile robots. An autonomous mobile robot gives name of its latest visited destination to an IDC which is located on a junction in a work area. An IDC summarize the information from robots and tell a direction which it expects best way to a destination which a robot want to go. By the proposed algorithm and system, mobile robots construct information of navigation and improve the efficiency of a task automatically. We verified the effectof the proposed algorithm by simulations and experiments.

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In this paper, a method for acquiring trajectory information from the object of task through a vision sensor to generate reference trajectory to a robot control system is proposed. The trajectory generation is done online and "on-task" (during the execution of the task). The whole image acquired from the vision sensor is processed to get the relevant trajectory data, taking considerable computation time if compared with the computation time of a robot control system. Making use of the preview characteristic of the vision information, a method for the synchronization of the image processing system and the robot control system, implemented separately, is proposed. This synchronization method allows the application of the proposed system in image pocessing systems with low frame rate. The proposed method is experimentally verified by applying it to a force and position control system of a translation/rotation-decoupled direct-drive (DD) robot, of which the generation of the desired trajectory is not a trivial task. The image processing is performed on images grabbed from a CCD camera installed on the robot arm and the desired trajectory is generated online.

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Toward elderly society, development of machines for assisting human walk is getting more important nowadays. Some assisting machines of a cart type have been developed. However, it has not been clarified how the machines effect the generated muscle tensions and energy consumption of human users. In this paper, we have evaluated a human walk using the cart which was developed for this research. We estimated the energy consumption based on the muscle-skeleton model. It is shown that the energy consumption using the cart has decreased by 15% of the normal gait. Our evaluation method will be useful for developing practical assisting machines.

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In order to measure the contact area between mirror surface and regular rough surface with in contact by ultrasonic pulse reflection method, fundamental characteristics were experimentally examined under the stationary conditions. Obtained were that the reflection echo height ratio H from the contacting boundary is dependent not only on the normalized contact area but also on the nondimensional pitch Λ which is the ratio of the pitch of contacting spots to the ultrasonic wave-length. It was also revealed that the relationship between Λ and H can be expressed by a simple equation considering spring stiffness between two solid surfaces. As the reflection echo height not be influenced by the pitch and arrangement of contacting spots in the range of Λ > 1.5, it is possible to estimate the normalized contact area straightforwardly from H. In the usual case of Λ < 1.5, it is possible to estimate the normalized contact area with measuring the change in the reflection echo height under several incident wavelengths.

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In an autonomous space docking system using a variable geometry truss (VG-T), a docking port is controlled to a direction of a target satellite approaching with various postures and velocities. Consequently, the motion of the target has to be identified, where the target is to be measured at the position apart from the docking system. This paper is concerned with three dimensional measurement of the position and posture of the target as well as the object recognition by using a stereo vision. A hierarchical shape description graph is introduced to perform the stereo matching and model matching efficiently. The normalized fitting function is introduced to reduce an error of the model matching. If values of the fitting function for all of the database model are lower than a threshold value, the object is treated as an obstacle. The efficiency of the proposed system is demonstrated by an experiment.

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An autonomous space docking system requires a visual sensing system for distinguishing a target object from the surrounding environments including obstacles and tracking the motion of the target. This study is concerned with the visual sensing system for tracking the motion of the object. Using a stereo vision system, three dimensional position and posture of a target object are measured. Then, the reconstructed object is identified by model matching with a CAD database. However, this process requires several seconds on personal computer. In order to estimate the motion of the target in real time, a single camera vision is adopted. The single vision captures feature points in high speed. Then, the feature points are identified by comparing with feature points of the previous image which are already obtained. Combining both processes by multi-thread programming, the proposed vision system can track the three-dimensional motion of the target.

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In the field of condition diagnosis of machinery, one of popular and practical methods is vibration analysis. Recently, dimensional and undimensional symptom parameters have been used for the condition diagnosis. However, these parameters can not be used to precisely detect failures of machinery in unsteady operating conditions, namely, in this case, the rotating speed and operating load of the machine are always changing. In order to overcome this difficulty, this paper proposes a new methods, by which the optimum symptom parameters can be automatically generated by Genetic Programming and the optimum frequency band can be decided to extract failure signal by Wavelet analysis for the precise diagnosis. The efficiency of the new methods is verified by applying them to the condition diagnosis of rolling bearing.

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In order to clarify the grasping mechanism of tools and handles, we investigated, essentially, the finger joint pressures against cylindrical object and discussed the relatioship between the pressure change and sensory evaluation in grasping cylinder depending on load and diameter. During the grasp, finger joint pressures increased, transiently, immediately after loading and then decreased gradually to the stable pressure for 10 sec and after. The pressure at stable period was larger than the pressure at which the cylinder slipped down from the hand. The decline of finger joint pressures were slight during grasping the cylinder with high value sensory evaluation. But the tendency was weak during grasp with high load. The present results suggest that the mechanism under grasping depends on the load and the diameter of cylinder object. And the force modulation is consider to be influenced by the sensory evaluation for grasping.

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An error compensation method for tooth form grinding works of an involute helical gear is proposed. Not only setting errors of a grinding wheel but also truing errors of it are concerned into the machining model. Profiles of tooth form are measured by a touch sensor, which is attached on the NC grinding machine. Distance between the profile data and tooth surface is expressed by nonlinear equations with constraints of implicit functions. The truing error and the setting error of the grinding wheel are derived as the distance between the actual tooth form profile data and the model tooth surface equal to the probe radius. Jacobian matrix, which is used in least square calculation for the error estimation, is derived by applying higher order differentials of the nonlinear equations and the implicit functions. The proposed algorithm was confirmed by numerical simulation.

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An over-ball measurement of straight concave conical gear is developed. This method is based on the over-ball measurement of the straight conical involute gear. The tooth surface of the concave conical gear is different from that of the conical involute gear, and besides it is concave in comparison with the tooth surface of the conical involute gear. So the over-ball measurement of the conical involute gear can not be used as it is, but can be used on a special condition. First this condition is found, and the over-ball distance is obtained analytically. This over-ball measurement is verified by experiments. Next how to control the finishing dimension is presented. Finally how to apply this measurement to controlling the infeed distance in practical hobbing and grinding is presented.

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Authors reported theory of hourglass worm gearing whose worm is generated by high speed screw generating method, on 1 st report. CNC high speed hourglass worm generating machine has been developed according to the theory. And worm cutting test and performance test of worm gearing was made. The test results are as follows: (1) Newly developed machine has high speed cutting ability same as mach type screw generating apparatus. (2) Surface roughness of worm tooth surface generated by the CNC high speed hourglass worm generating machine has same order of roughness of screw surface cut by mach type screw generating apparatus. (3) Hourglass worm gearing generated by the newly developed machine showed high efficiency and ran 1000 hours without trouble.

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To examine the effect of the difference of grease lubricating method on the scoring resistance of the stainless steel SUS 440C gears of which the surface layer was thermally diffused after being Sn-plated, scoring test was carried out by power-circulating gear test rig under forced lubrication, bath lubrication and spread lubrication. From the test, the following results were obtained. Under bath lubrication, the scoring resistance of the gears with the diffused layer was about 4.3 times as high as that of the gears without the diffused layer. Under forced lubrication, the scoring resistance of the gears with the diffused layer was about 2 times as high as that of the gears without it. Under spread lubrication, the destructive surface failure by scoring occurred on the meshing faces of the gears without the diffused layer after 20∼30 mins since the test run. But, for the case of the gears with the diffused layer, scoring did not occur while the test was running.

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Copper alloys are widely used as conductors in electrical equipment. In these cases the mismatch of thermal expansion coefficients between copper alloy and other materials may cause frequent mechanical problems. For instance, in bolted joint structures the mismatch of thermal expansion coefficients causes transverse cyclic relative slippage and loosening of bolts. In this paper the relaxation behavior of these bolted joints was analyzed by considering the relaxation characteristics of the jointed body, and the tlnermal expansion mismatch between steel bolts and jointed body materials. The analytical results were confirmed by the experimental results. Using these results we can propose some fastening criteria for maintaining long-term reliability.

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In order to understand the dynamic characteristics of flexible seals for reciprocating motion, the relationship between film behavior between sealing surfaces and friction characteristics is investigated based on direct observations using the optical interferometry technique. A nitrile rubber band with a D shaped cross section instead of actual D-rings was pressed against an oscillating glass plate. The effects of the length of stroke and surface defects are also examined. It has been found that even in the mixed-lubrication regime rather thick oil films are formed during the reciprocation. However, when the length of stroke is less than a certain critical value, the film completely collapses even in the hydrodynamic lubrication range and the reciprocating motion is established by the deformation of the rubber specimen. The surface defects such as dents and bumps bring about local fluctuation in film thickness downstream of these defects.

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A modified Reynolds equation derived with centrifugal force acting on lubricating oil film being considered is solved for the hydrodynamic pressure in the concentric oil film of very high speed journal bearing. The linear rotordynamic coefticients are calculated with the axial oil film rupture being considered. This method yields new linear stability charts of very high speed floating bush journal bearing, which can explain its stability' behavior observed in actual machines.

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A duplex surface treatment of tool steel, which comprises of nitriding of a substrate and coating of a titanium nitride (TiN) layer, is studied as a potential tool material for plasticity processes of aluminum alloy without lubrication. Tribological properties are determined on a ring on-block arrangement, where the ring is made of aluminum alloy, A6063, and the block is made of the TiN duplex treated alloy tool steel, SKD61, and is compared with untreated, nitrided, and TiN ion-plated alloy tool steel. At higher loads and higher speeds, transfer of the aluminum alloy onto the tool steel occurs, which is little improved by the treatment. Wear of the tool steel takes place as the predominant mode of surface damage at lower loads and lower speeds, and is markedly reduced by the duplex treatment. Possible mechanisms of the improvement are discussed.

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Bending limit and deformation behavior of braided thermoplastic composite tubes by a new roll bending process in thermoforming are studied. The composite tubes with four kinds of initial fiber orientation from 18 to 47 degrees are fabricated by internal pressure bonding method, and used in the experiment. The roll bending process was performed by a newly developed roll bending equipment based on locally heating and cooling technique. Bending radius, fiber orientation, bending strain and circumferential strain of grids are measured. The experimental results show that the bending limit improves with increasing initial fiber orientation. Undesirable deformation occurs easily at inside and side of bent part in the case of small initial fiber orientation. The experimental bending limit agress with the calculated one obtained from geometrical configuration. The bending limit is affected by critical fiber orientation at outside of bent part and undesirable deformation at inside to side areas. It is confirmed that kinematic deformation mode of the braid with small initial fiber orientation in bending process contains not only the trellis effect but also slipping mode which also plays an important role in the roll bending process.

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For obtaining higher finishing efficiency of diamod lapping films, the dynamic properties of rubber used for contact rolls pressing the diamond lapping films against ceramic workpieces were estimated. By examining the frequency response of rubber, the visco elastic characteristics were clearly recognised in detail. And, the contact conditions between the diamond lapping films and workpieces were examined by measuring the normal contact force throughout the different infeed processes. From the experiment, the effects of infeed speed and the set depth of pressing of lapping films on the normal contact force were clearly understood. For the purpose of obtaining a higher stock removal rate in the finishing process utilizing the dynamic properties of rubber contact roll, the infeed repetition finishing method was proposed and examined. By utilizing this control method, and by changing the amount of infeed and the infeed speed, the effects of this infeed method were confirmed.

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It has been recognized from many investigations on water jet cutting mechanism that visualization of a cutting front is very effective to deepen understanding of the mechanism. However, an in process visualization method, especially those applicable to opaque materials such as metals has not been established even now. This paper newly proposes a method of visualization of cutting front using ultrasonic waves. Several experiments have shown that in-process visualization of a shape of the cutting front, inclination and profile wariness of cutting surface can be realized using the proposed method. Furthermore, this paper also proposes a water jet cutting process model based on detail analyses of visualization results.

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Error compensation system in longitudinal turning process is developed with prediction model. This paper discusses dimensional error of general product shapes having taper steps for practical use of the system. Expression of product shape is an important issue of this study because geometrical features can not be specified before operations. One shot cutting is performed before operations so that system can acquire compliance of workpiece to be machined. System can recognize the geometerical features as compliance of each cutting position. In prediction model, cutting force, cutting temperature, and flank wear are analyzed; and then dimensional error is associated with past similar operations by neural network. System, therefore, predicts dimensional error for the recognized shape in any cutting conditions with cutting tool geometry; and compensates for predicted error by modifying depth of cut. Some experiments, where workpiece has a taper step, show the system can keep high machining accuracy with considering the effect of cutting conditions, coolant, flank wear, and the change of product shape on machining error.

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As a basis for establishing a method to evaluate the thermal shock resistance of brittle tools, we irradiated CO₂ pulse laser beam on a cemented carbide tool to apply pure thermal shock and examined the states of thermal crack. The experiments were carried out on the condition of no melt on the beam irradiation surface. The crack appears at the beginning of the beam irradiation off time. Similarly in intermittent cutting, the crack is perpendicular to the cutting edge for the laser beam irradiation near the edge. The analyses of the temperature rise and thermal stress on the beam irradiation surface and in its neighborh∞ud have demonstrated that no tensile stress appears on the surface; in the region below the surface, the stress field is widely formed where the three principal stresses are tensile; the primary principal stress is always tensile and becomes maximum immediately after the beam irradiation.

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The effects of surface roughness on the optical properties of metals have been discussed by comparing experimental results of ellipsometry with theoretical results from the homogeneous effective medium model (HEM), the monolayer effective medium model (MEM) and the gradual density layer model (GDL). A gradual increase of |r_p/r_s|(=p) has been observed with the increase in surface roughness at a higher angle than θ_B and gradual decrease at lower angle than θ_B, where θ_B is the pseudo-Brewster's angle. Though HEM models do not explain the roughness effect on optical properties, MEM model and GDL model show good explanations for the optical effects from rough metal surface, when Δd<<λ.

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Numerical control technique is widely used for controlling 2 or 3 axes driving machines such as machine tools or industrial robots by giving many pulse series to the industrial machine. NC languages for numerical control has been already prepared for driving many industrial machines and applying commands of the NC language the interpolation of the straight line or circular curve about trajectory line of tools can be realized easily. But the multi-axes machines or articulated industrial robots don't have the perpendicular coordinates, so DDA (Digital Differential Analyzer) technique that is a technique for the interpolation of straight line or circular curve cannot be applied to control multi-axes driving machines like 6-articulaled robot arms for the trajectory line of tools or robot hands. In this study, new NC controller that involves the forward kinematics of robot, its inverse Jacobian matrix and V-F converter is proposed by the computer software. The new NC controller that is proposed in this study is made by a feedback loop in the computer software and can generate on-line pulse series for realizing a desired posture and orientation of robot hand.

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The ultraprecision positioning is examined against the fine feed system utilized the elastic deformation of lead screws accompanying preload change in double nuts. The nonlinear deformation due to Hertzian contact of ball screw can ignore within a feed of 1 μm under adequate initial preload. The influence of load on table displacement of nanometer order is not observed in the range from 10 to 50 kg. The displacement obtained under increase in preload coincide well with the result under decrease in preload also. Feed control with preload change based on one to one correspondence of preload change and displacement is effective to avoid the hysteresis phenomenon of PZT actuator adopted as deformable spacing part between double nuts. Further, preload can use as a measure to detect table displacement in place of position sensor which sometimes shows unreliability owing to unstable situation in nanometer region. The minimum step feed deduced from preload change is 1 nm for sliding screw and 5 nm for ball screw.

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This paper elucidates the effect of rotational frequency ω of OD-blade on the compliance of its outer edge (hereafter, it is referred to as "edge compliance"), taking up two types of blades welI used for the high-precision slicing of AI₂O₃·TiC. One of those is the sintered metal-bonded diamond blade(Type A) and another is the electroformed diamond blade(Type B). The obtained results are summarized as follows. (1) Young's modulus of Type B is about 3 times larger than that of Type A. (2) The blade deflection around the load point decreases with the increase of ω, but the deflection at the circumferential distant point from the load point increases slightly. (3) In case of the blade of type B, the effect of co on the edge compliance is very small. (4) In the range of ω≤50000 rpm, the decrease ratio of the edge compliance becomes large with the increase of ω. (5) Under the slicing conditions generally used for high-precision slicing, the effect of ω on the edge compliance is very small. (6) The larger the blade protrusion φ from flange, the greater the effect of ω on the reduction of the edge compliance. (7) The edge compliance varies inversely with the decrease of the blade thickness t= under the condition of φ=20t, almost irrespective of ω. (8) With the decrease of the blade diameter, the edge compliance reduces a little under a high constant peripheral speed.

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The formulas for kinematic analyses of the spatial 7R 7-link mechanism are established in the case where three adjacent revolute axes and two adjacent revolute axes intersect a point, respectively. Static analyses of this spatial 7R 7link mechanism are performed by using the RRSS spatial fourlink mechanism, centers of whose two spherical pairs coincide with points of intersection of three and two revolute axes, respectively. Conditions for the limit position of the driving link are derived from the denominator of velocity analysis formula and the transmissibility of the forces acting on pairing elements. It is shown analytically and experimentally that the perpendicular distance from the center of the spherical pair of the stationary link, to the plane, which includes the axis of the revolute pair and the center of the spherical pair of the coupler link is useful for evaluating the motion transmissibility.

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This paper presents a proposal to improve productivity and provide a more reasonable work area. The method of research is to observe and measure the motion characteristics of a typical standing worker doing "get and place." The valuation index used in the experiment is obtained by measuring the characteristics of subjects (height, shoulder width and the height of Radial above the floor), the motion locus of Acromial, the Angular velocity of Elbow, the motion time and the amount of myoelectric discharge. The results lead to an experimental formula expressing the relation between the motion time, height of work desk and Angle of elbow. This paper also showed that a height of work desk and angle of elbow, which takes into consideration the difference of a physique of the worker, could minimize the motion time resulting in a more efficient and reasonable work place.

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In this paper, the analysis approach of flexible control on material handling operation in container terminal is presented. By considering the fact that container operation can be regulated by means of production management mechanism, the conventional queuing model is modified by its flexible operation model. To realize the optimum operational performance such as minimum ship waiting time, according to the variation of system status parameters, the operation rule and operation scheduling of quayside container cranes are dynamically determined with knowledge-based controller in the form of fuzzy neural network. The whole analysis process is divided into four steps: simulation execution, system status evaluation, system status prediction, and decision making on the coming operation rule. An actual case has been studied to demonstrate the effectiveness and validity of the presented model. By comparing with those from a conventional model, the results have shown that the flexible operation model can yield satisfactory oparational results.

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