In the strain wave gearing, the flexspline is a thin-wall cylinder with external teeth, the circular spline is a rigid ring with internal teeth, and the wave generator is an oval bearing. The main purpose of this study is the numerical evaluation of the stress in the flexspline which is the key element for the motion transmission in this components. When 'the flexspline is deformed into an elliptical shape by repeated load from the wave generator, the fatigue strength at the root of the tooth in the flexspline is a serious problem. The cup type strain wave gearing is modeled for FEM analysis. In the three dimensional field, the work ball of bearing and the oil film are modeled. And 16 nodes element is used as the contact element to consider the contact problem between the teeth of flexspline and circular spline. Deformation shape of the flexspline, various stress distribution at the root of tooth in the flexspline, and load of the bearing ball are calculated. The results show good agreement with experimental measurement qualitatively and quantitatively.

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The incremental transfer stiffness coefficient method is developed in order to analyze the periodic steady-state vibrations of a large-scale structure having locally strong nonlinear elements. The present method is based on the concepts of the method of harmonic balance, the transfer stiffness coefficient method and the incremental method. Firstly, in the present method, the structure treated is separated into the linear parts and the nonlinear elements, and the inner degrees of freedom of the linear parts are eliminated from the process of successive approximation for the solution by applying the transfer stiffness coefficient method. Secondly, the computation technique as the transfer influence coefficient method is applied to the above process to reduce the computation cost remark-ably. As a fundamental example, an algorithm based on the present method is formulated to analyze the in-plane flexural forced vibration of the straight-line beam structure supported by the nonlinear base support elements.

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By applying the incremental transfer stiffness coefficient method suggested in the previous report to a large-scale nonlinear structure, the stable and unstable solutions can be computed without distinction. Therefore, the stability of the solution obtained has to be analyzed. It is, however, very difficult to analyze the stability of the solution of the large-scale nonlinear structure. In order to overcome the difficulty, the method to reduce the dimensions of the structure without the decrease of accuracy is developed by applying the concept of the modal analysis to the stability analysis of the variational equation. Two types of modal matrices are considered in the reduction of dimension, and the method is proposed to select rationally the modes that dominate the stability of the solution. The validity of the incremental transfer stiffness coefficient method and the method of stability analysis using reduction model is confirmed by the numerical computational results.

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In this paper, the effects of the natural frequencies of ball and head are investigated on the restitution performance in order to develop a superior club head with high restitution performance. Firstly, the coefficient of restitution is calculated by using the lumped mass models of ball and head. As a result, the coefficient of restitution increases when the natural frequencies of ball and head where the contact part is fixed or free, coincide with each other. And the coefficient of restitution is bigger when the natural frequencies of ball and head where the contact part is fixed, coincide with each other than when the natural frequencies of ball and head where the contact part is free, coincide with each other. Next, the ball and head are modeled by three-dimensional models and the release velocity of ball after impact is calculated. As a result, the maximum release velocity of ball can be obtained when the natural frequencies of ball and head where the contact part is fixed, coincide with each other.

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A precise and stiffly stable time integration method with numerical dissipation is presented for solving MCK type equations of motion. Its algorithm is assumed that acceleration during time step is expressed as a quadratic function. Stability and accuracy are investigated by numerical analysis to find out the best parameter values of the algorithm. Characteristics of this method are compared with other methods such as Newmark, Wilson, HHT-α method, etc, which showed that this method has much better accuracy for low frequency modes, and strong dissipation for high frequency modes. Some calculation examples are shown.

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This paper investigates moving characteristics of a mobile mechanism. The mechanism is the combination of a pair of the bodies which are consisted of the particle and the slant leg with the rotational spring at the joint. Each component body alone travels forward and backward in straight line on the floor under harmonic excitation, and the moving velocity depends on the exciting frequency. This is caused by the difference in friction force between forward and backward directions during stick-slip motion. By combining these bodies, new motion is obtained, i. e., the mobile mechanism can achieve rotation as well as straight movement. This characteristics is obtained by tuning natural frequencies of the component bodies. Numerical simulation and experimental results show that the moving and angular velocities are controlled by the exciting frequency.

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This paper describes sound transmission reduction control through thin plate by using piezoelectric ceramic sensors and actuators, both of which are bonded on both surfaces of the plate. 2-DOF control system is introduced to reject the effect of bending vibration of the periodic component and continuously distributed component over the broad frequency range. The adaptive feedforward control is realized by using FIR filters and LMS system identification algorithm. The filtered epsilon with delay system is applied to cope with the non-minimum phase of the identified feedforward control systems. The internal model control is introduced to the feedback control system, which are constructed basically with the direct velocity feedback (DVFB) system. The internal model control was efficient to suppress the howling instability to occur frequently in case of high feedback gain. The substantial reduction of the sound radiation from the plate in the control experiment proves the effectiveness of the 2 DOF control system.

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In the active noise control, a transfer characteristics of an acoustic feedback path has a consider-able influence on the stability of the control system. When an acoustic system has a feedback path, the control system often causes unstable behavior called howling. An approach to prevent the howling named directional control sound source (DCSS) is investigated and compared with an ordinary approach (howling canceller) in this paper. This DSCC is composed of two sound sources and a finite impulse response (FIR) filter. Active noise control using the filtered-x LMS (Least-Mean-Square) algorithm is carried out in an L-formed duct model. It is shown that the DCSS approaches prevented the howling effectivery through the experiment.

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To improve efficiency and reduce costs, it is necessary to reduce the number of steps is the rotor development process. This can be achieved by combining the use of CAE and computer-aided optimization (CAO). To meet the increasing demand for CAO in the rotor dynamics design field, we developed a rotor dynamics design support system. This system provides a FEM-based rotor dynamics analysis function, and the design of the experiment is based on a CAO function. In this paper we will explain the CAO function, as well as provide a case study on second bending vibration mode optimization, which is generated by an imbalance in a damper bearing supported model rotor.

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The induction motor is superior to a dc motor in maintenance. Though the control of induction motor is much more difficult than that of dc motor, it is currently used by realization of so-called vector control method. But, this method doesn't establish the stability of the system, neither is robustness. The dynamics of the induction motor is represented by nonlinear equations with three-inputs and three-outputs. Though precise parameters are necessary for the vector control method, it is generally difficult to obtain the precise values. Therefore, there are often identified errors in parameters. In this case, as the effect of the nonlinear terms remains, it is known that chaotic motions may occur in the system. As chaotic motion isn't necessarily desired for the system, it's necessary to remove the chaotic behavior when this behavior occurs. In this paper, the existence of chaotic motion in the system can be verified, and the generating conditions are found using Lyapunov exponents. Next, a chaos control method using neural networks is proposed in order to remove the chaotic behavior.

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The purpose of this study is to propose a robust control strategy on high-speed positioning of pneumatic servo system, for the changes of system parameters and load mass, and frictional force. Bang-Bang control scheme based on the switching time is one of the most efficient control strategy for high-speed positioning, however this control scheme is influenced by the changes of system parameters and load mass because of the open-loop control. In order to overcome these defects, a concept of disturbance observer is introduced into Bang-Bang control scheme. That is, the changes of system parameters and load mass can be estimated by a disturbance observer, and the switching time in Bang-Bang control can be modified so as to correspond to the changes of system parameters and load mass, under controlling. It is investigated that the proposed control strategy is effective for the robust high-speed positioning of pneumatic servo system with a pneumatic rodless cylinder, through some experiments.

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As a controllable damper, magnetorheological(MR) damper can play an important role in the vibration control system, especially as a semi-active control device. In this paper, an experimental setup has been made for investigating the characteristic of MR damper and analyzing its vibration isolation characteristics. The analytical model that consists of a hysteresis part and a variable viscous damper proportional to the added voltage is used to describe the performance of a MR damper. Two on-off damper control policies based on the product of relative velocity and relative displacement are proposed. The numerical simulation and experiment are performed to investigate the effects of the two kinds of on-off dampers and conventional on-off damper in the single-degree-of-freedom system. The results show that on-off dampers express the better vibration performance than the uncontrolled MR damper, two proposed on-off dampers have the better vibration performance in the high frequency domian than that of conventional on-off damper, and the controllable MR damper is very effective for vibration control.

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Applicability of a smart structure using piezoelectric actuators was investigated for active control of wind-induced vibration of buildings in which piezoelectric actuators of stack type were attached to the bottom parts of the columns for their bending moment control. A large-scale piezoelectric actuator consisting of 30 piezoceramic plates of a 100 mm×100 mm×5 mm^H outer size was fabricated and tested, showing satisfactory results that the maximum displacement under a 196 kN initial compressive load was 94×10^-6 m, and the maximum force under zero displacement condition was 270 kN, when a 3.0 kV voltage was input. Simulation studies showed that the smart structure using the large-scale piezoelectric actuators could have almost the same performance as a current active mass damper for an actual 9-story building of a 30.65 m height and a 273 t total mass.

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In vibration isolation control problem, semi-active control methods in which coefficient of viscous damping or spring constant are varied effectively have been proposed and expected to realize a high performance with a little energy consumption. However, the semi-active system is classified into a bilinear system which belongs to a nonlinear system and its controller design is not easy. In this study, a bilinear optimal control theory is established by adopting the damping force in criteria function and it is applied to a semi-active base isolation problem. This study deals with 10 stories structure model corresponding to an actual building and the dynamics of an oil damper is taken into consideration by using the Maxwell model in the modelling. Moreover, the dynamics of disturbance is taken into account, and the controller is designed for the augmented bilinear system which includes both the control object and the disturbance. And the computer simulation is carried out by taking account of the delay to switch the coefficient of dampers in order to compare the performance on semi-active base isolation controls designed by the proposed method with skyhook control method and passive isolations. As a result, the usefulness of the present method was demonstrated.

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This paper deals with control of a crane mounted on a tower-like flexible structure called the "Tower crane" by using no sensor for the load-rope angle, since it is difficult to put the sensor on a real tower crane. We make its models and design the two-degree-of-freedom control system. The feedback controller that does not use the sway angle signal is designed by considering the coupling between the load sway and the crane itself. The feedforward input is designed by the final-state control method with error learning. By experiments it is verified that the 2 DOF controller without the sensor for the load-rope angle has almost same performance as the feedback controller alone with the sensor.

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Tendon control is studied for the vibration control of flexible structure, for example robot arm and large space structure. It is a remote vibration control method using actuator and wire. But, compressing force of flexible structure occurs by Tendon control and the transfer effect of control force is often small depending on the size of mechanism. In this paper, a parallel supporting damper with Tendon in proposed. A supporting element is parallelly assigned for the flexible structure. And, vibration is reduced like dynamic absorber by reciprocal action between the flexible structure and the supporting element connected to each other by wire. The proposed structure avoids compressing flexible structure and transfer effect of control force is improved. A vibration control system is designed based on H_∞ control theory. It is shown that property of proposed method is better than that of conventional method by numerical simulation.

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A measurement system constructed with a micro fizeau interferometer and the spatial fringe analysis method is proposed to measure precisely a deflection of micro structures. The results of the deflection are given as the boundary condition of the FEM. A stress in the element is analyzed by the FEM. To confirm the validity of the principle, the experiment is performed with a macro model. The measuring optical system for the macro model is constructed with a projection moire system. Without any contacts, the stress map in the element can be estimated by this method. Comparing the results from this method and strain gauges, it confirms that the accuracy of the estimation of the stress is less than 5 MPa in the macro model. On basis of results in the macro model, a stress in a micro cantilever can be estimated.

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In quantized control systems, the control can take only given discrete (e, g. integer) values. Optimization of these systems has conventionally perrormed by mathematical programming (e. g. Dynamic Programming) methods. In this paper, the authors present a reachable theorem and the control algorithm for optimal solutions in a quantized discrete-time linear system with rational coefficients. Further, they formulate a quantized minimal discrete-time linear control problem of the small-scaled Hydro State Transmission (i. e. HST), and obtain simulated optimal solutions used by this algorithm.

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This paper is concerned with the development of an active palpation sensor for detecting the prostatic cancer and hypertrophy. The receptor of the sensor is a polyvinylidene fluoride (PVDF) film placed on the surface of a sponge rubber layer. It is fixed at the end of a slender bar and, being protected by a medical rubber glove, inserted into the examinee's rectum. After positioned face to face to the prostate gland, the sensor probe is driven sinusoidally at about 50 Hz with peak-to-peak amplitude 2 mm. The voltage signal from the PVDF film is integrated over the sampling period and used as the output of sensor for extracting the features of the collected data. The evaluation of stiffness by the sensor on 27 normal and unhealthy prostate glands are compared with the results of diagnosis by the doctor's palpation. It is shown that the output of sensor becomes greater with an increase of the stiffness of the prostate gland, which has good correlation with the doctor's evaluation on the stiffness. Further results on the laboratory test reconfirm that the present sensor well discriminates the stiffness of the prostate glands in vivo and non-invasively.

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Twin rotor helicopter model has a similar dynamical property to that of VTOL aircraft. Our purpose is to find an appropriate design procedure, and to show that validity through experiments. First, two step linarization method is applied. Namely, the plant is partially linearized by applying static feedback linearization to the main and lower subsystems hierarchically, and PD controller is designed. Experiments show the good property of the control system except for disturbance rejection. Second, H_∞ controller and feedforward controller are added to the linearized system in order to improve disturbance rejection and tracking.

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This paper describes two types of head positioning mechanism of hard disk drive comparatively. One is a conventional swing-arm positioning mechanism with a minor-loop analog feedback controller that stabilizes the primary out-of-phase vibration mode. An observer circuit estimates a velocity of the vibration mode from VCM voltage and current. Estimated velocity of the vibration mode is fed back to stabilize the vibration mode. The other one is the in-phase positioning mechanism that has a sub-actuator for track following. A swing arm head positioning mechanism that has both of main-and sub-actuator was manufactured to confirm the effectiveness of the minor-loop feedback and in-phase positioning mechanism. Characteristics of two positioning mechanisms are shown with simulation and experimental results.

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Path following is a popular task for robotic use. The conventional approach for the path following consists of two stages. At the first stage, the desired state of a robot is computed as a function of time before the robot executes the task. And at the second stage, the robot is controlled to track the desired state. Since the objective of the original task is to follow the reference path, the velocity of the robot or timing is not needed to be controlled strictly. In this paper, a new approach to make the robot follow the reference path is proposed. This approach defines the desired state as a function of a parameter φ, which has a dynamics. By using a Lyapunov function, the global asymptotic stability of the system is proved. Computer simulations show the effectiveness of the proposed method.

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In this paper a force and vision sensor fusion method is proposed in order to extend the conventional force and position hybrid control. The purpose of this system is to apply a controlled normal force on a surface with unknown shape. We achieve our objectives by using a partially reconstructed trajectory, visualized by one CCD camera installed on the end-effector, and complementing it with the tactile information provided by a force sensor. Based on the force sensor information, the normal and tangential directions of the constraint surface are identified and the desired point, obtained from the CCD camera, is projected back to this surface. The only assumption done here is that the surface is smooth enough to allow us to do a good estimation of the constraint surface. This method was developed in order to simplify the use of the 6-DOF direct-drive (DD) robot proposed by Utsumi and Todo, which was initially designed to do polishing tasks. The referred DD robot was designed with a particular structure in order to lower its whole weight : a 3-DOF parallel link arm robot and a 3-DOF orientation table. By using this system, the user can easily draw an arbitrary path on the surface of the object before he fixes it on the orientation table, without thinking about complicated curved path and surface equations or coordinate system transformations.

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In the study, we deal with a human/robot coexistence system for their collaborative tasks of conveying works or tools in which the robot partially assists the human power. Special focus is on discussing the technical requirements for reflecting the operator's intentionality which includes both : on which pre-assigned path the operator intends to convey a work or a tool and how much of load pattern he/she desires to feel along the path, both in collaboration with the robot. First, after defining the problem of inferring the path intended by the operator as a pattern matching problem of isolating a path out of the preassigned ones with an incipient sequence of the detected trajectory data, we provide the system with a capability of inferring the operator-intended path pattern so that the robot can trace one of the preassigned patterns. Second, we propose a "Field Impedance Equalizer (FIE)" with which the operator is able to determine location-dependent mechanical impedance of the human/robot system and generate the desired motion patterns through verbal communication from the oprator to the robot. Experimental results show that, with the aid of the proposed human interface, the human/robot cooperative motion generated the desired force pattern to merge so as to comply with the velocity pattern which was verified to have only a small deviation throughout the trial even from the beginning.

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In this paper, we discuss an issue relating to the force/moment transformation for the handling of a large object by multiple mobile robots in coordination. We propose a control algorithm using geometrical constraints among the grasping points and the representative point of the object, which reduce the effect of sensor noise amplified by force/moment transformation. We extend this algorithm to the decentralized control algorithm of multiple robots handling an object in coordination. The proposed control algorithm is experimentally applied to multiple omni-directional mobile robots. Experimental results illustrate the validity of the proposed control algorithm.

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Mobile robots with a new type of movement called wavy movement will be proposed in this paper, Up to now, stair climbing robots can be roughly classified into crawler, leg and wheel types by their movements, but there are still some problems in each type. A crawler type is heavy and complicated, a leg type is hard to control, and a wheel type can not get over big obstacles. A robot with wavy movement, which can be readily realized by rotating bars or crosses, is able to ascend and descend stairs with simple structure and easy control method by covering corners of stairs within separate wave shapes between touching points. The principle of wavy movement, the mechanism, and the experimental result of the proposed robot are discussed.

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Bayesian estimation is often applied in pattern recognition problems. We formulate estimation errors of a posteriori Bayesian probabilities to be propagated from observation. Next, we apply the scheme of the formulation to a practical image recognition problem : based on a posteriori probabilities, sectionalized regions in outdoor-scene images are classified into five categories of landform elements, i, e., asphalt, concrete, sand/soil, gravel, and grass. The errors originate from RGB pixel values, and propagate to the a posteriori probabilities via intermediary HIS color measures within a region. We concretely clarify a mechanism of the propagation for all steps, and show an effectiveness of the scheme by adducing changeovers between a posteriori probabilities with two kinds of landform elements.

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In order to reduce the lateral force between wheel and rail during curve negotiation of rail vehicle, some kinds of bogie truck with actively steered wheelsets have been investigated. This paper deals with a basic study about the actively steered truck, which employs a control law based on the self-steering ability of wheelset, measuring the relative yaw angle between the wheelset and the bogie frame. However, this control law helps not only the steering performance, but also the occurrence of running instability. Therefore, two methods are proposed to improve the stability. One is the method that adds the wheelset lateral velocity as the feedback state, and the latter is the one that gives some time lag to the control moment. Both methods are proved to be affective for the stabilization. Here, the latter is more practical because it does not need further measurement. Then, it is also confirmed that the control lag of the latter method does not deteriorate the steering performance under the practical curving condition with track irregularities considering the dynamic characteristics of electro-mechanical actuator.

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In the present study, we developed a simulation model of human-wheelchair system in order to support the design of the wheelchair transporting apparatus. First, we modeled the system as a seven-D.O.F. dynamic model of two dimensions. This model has some parameters of unknown value. Secondly, we conducted modal analysis to clarify the modal parameters on the system. Thirdly, we solved the equation of motion including the modal parameters. As a result, the model was identified because the unknown values of parameters on the model were obtained. Finally, model simulations were practically performed by varying the physical parameters. It is found that the identified model was effective for improving comfortability in riding of the wheelchair transporting apparatus.

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In the present study, due to improving comfortability in riding of the Wheelchair Transporting Apparatus, we analyzed the relation between vibration and evaluation for the vibration. In the exciting experiment, the vibration on the floor and human body was measured by acceleration sensors, and the evaluation of nine parameters for the vibration was measured by SD method. First, we analyzed the relation using the correlation analysis. It is found that the vibration on upper part of torso, especially in up-down direction, correlates with the evaluation of comfortability. Secondly, we clarified the relation between the vibration and the evaluation by multiple regression analysis. As a result, we obtained reasoning model and criteria of comfortability in riding.

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Averaged Navier-Stokes equations with turbulent coefficients and the continuity equation are applied to a theoretical investigation of the effects of inlet swirl velocity on the static characteristics of annular plain seals employed in pumps. The turbulent coefficients are calculated based on the "law of the wall" and Prandtl's mixing length hypothesis. The Navier-Stokes equations and the continuity equation are numerically solved in consideration of the eccentricity of the rotor in the seal. The numerical results show that the inlet swirl velocity significantly influences the circumferential fluid velocity, which increases as the inlet swirl velocity increases in the direction of the rotor spin. For the eccentric seals, this phenomenon enhances the wedge action induced by the circumferential flow, and yields large hydrodynamic fluid-film pressure peaks and tangential fluid-film force. Hence, the effects of the inlet swirl velocity on the fluid-film pressure and the fluid-film force in the seal clearance qualitatively correspond to the effects of the rotor spinning velocity on these characteristics.

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Averaged Navier-Stokes equations with turbulent coefficients and the continuity equation are applied to a theoretical investigation of the effects of inlet swirl velocity on the dynamic characteristics of annular plain seals employed in pumps. The turbulent coefficients are calculated based on the "law of the wall" and Prandtl's mixing length hypothesis. The numerical results show that for any eccentricity ratio at an equilibrium position of the rotor center and for any rotor spinning velocity, the inlet swirl velocity significantly influences the cross-coupled stiffness terms, whose magnitudes increase as the inlet swirl velocity increases in the direction of the rotor spin. This phenomenon yields an increase of the whirl-frequency ratio, resulting in a narrower stable range of the rotor spinning velocity.

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This study is to develop a new method to enhance the bending capacity of gear tooth by the use of asymmetric tooth profile. Considering that many power transmission devices operate in one direction, where only one tooth surface (the front of tooth) is practically used. Therefore, it is not necessary to make tooth profile symmetrically, the back profile of tooth, which does not mesh in operation, can be designed to decrease tooth root stress. Different standard pressure angles are used to the front and back tooth profiles. Finite element method was used to calculate the tooth root stress and the bending stiffness of the asymmetrical tooth in several standard pressure angle combinations. Based on the results of calculations, it is clarified that tooth root stress decreases and bending stiffness increases remarkably by the use of a large standard pressure angle in the back profile of tooth, but no clear change in load sharing ratio appears during meshing period.

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Reduction of tensile strength in helical cords during bending fatigue was investigated carrying out some experiments, FEM analysis and mechanical analysis. The cords were constructed of stranded glass filaments and Resorcinol-Formalin Latex, and were used in synchronous belts. The stranded glass filaments were de-bonded and the tensile strength was reduced after the bending fatigue. The FEM results showed that the reduction of tensile strength could be explained by the initiation and extension of the de-bonding in the cords. A simplified mechanical model was proposed to explain the reduction of tensile strength of cords.

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Power transmissions between crossed axles are used in several cases and generally performed by bevel gears. There is no report that deals with an application of traction drive to such transmissions. A prototype of crossed axle type traction drive using conical rollers was developed by the authors and its efficiency was evaluated. The power transmission efficiency of traction drive between conical rollers without the spin in the contact area is 98% and the disadvantage caused by the conical shape is not observed. A loading cam, which optimizes the contact force according to the loaded torque, is effective to decrease the loss torque of the transmission in the range of small drive torque. The mechanism of the loading cam is analyzed and this paper shows how to design the loading cam.

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Using an electric resistance method, the authors monitored continuously the state of oil film formation during operation of the type 6008 deep groove ball bearing under variously combined radial and axial loads. As lubricants, two kinds of mineral oils with nuch different viscosity grade were used. As a result of calculation, it was found that the extent of the loading zone and the increase in the normal load become remarkable in the case of a deep groove ball bearing as the axial load increases. In the running tests, it was shown that the increase of axial load has a large effect on the state of oil film formation of the deep groove ball bearing. Furthermore, it was recognized that the extent of the loading zone has a close relation to the coefficient of friction and the slip ratio of separator. When a low viscosity mineral oil was used, the load distribution had a significant effect on the state of oil film formation and on the running performance under the combined loads as compared with a higher viscosity mineral oil.

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This paper presents the effects of TiN coating and (Al, Ti) N coating films on the rake face of hob on the behavior of crater wear mainly, flank wear and finished surface roughness with using two kinds of high-speed steel hob substrates in dry hobbing. Experiments were carried out using a fly tool. As the results obtained, it was found that the tool made of corresponding to SKH 55 coated with (Al, Ti) N has no crater wear and also shows a best performance in terms of the flank wear and surface finish, and the corresponding to SKH 55+ (Al, Ti) N fully coated tool is suitable in dry hobbing. It was also suggested that the crater wear mechanism on the coated rake face is due to the plastic deformation of the coating film, which causes its delamination, after appearing the substrate, the crater wear increased by the abrasive action with the cutting chips.

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This paper describes the experimental analysis of temperature distribution of cutting tool during an ultra-precision diamond turning of aluminum and oxygen-free copper and the effect of cutting conditions on the temperature rise and the machining error due to the thermal expansion of cutting tool is discussed. The temperature distributions is measured by employing an infrared camera and the progress of the temperature rise at any points on the cutting tool is analyzed based on the images by using an image processing unit. The machining error, the relative displacement between the finished surface and the feed table, is measured by employing a capacitive-type proximeter. In this experimental conditions, the temperature rise at the sintered diamond tip reaches up to 15°C, while that at the single crystal diamond comes to approximately 5°C. The pattern of the temperature rise changes depending on the feed direction of the tool. The machining error is generated according to the progress of the temperature rise on the cutting tool and the magnitude becomes to an order of 1 μm.

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Single crystal diamond (SCD) has superior characteristics, so because its extreme hardness, SCD has become indispensable for precision machining as cutting tool. When SCD is used as products in practical field, it should be manufactured into arbitrary shape. In order to get bulk pattern of SCD, usually polishing diamond with diamond powder is done extensively, but this method costs and takes long time. This research is an experimental investigation of SCD precision machining by ferrous material, through utilization of tool wear during cutting process, in order to perform micro machining of SCD, for getting an arbitrary shape of diamond. It is found that ferrous material can remove and polish SCD, even though SCD is much harder than ferrous material. The removal rate has measured, the surface roughness of machined diamond is comparable with the surface roughness of commercial cutting diamond, and much better than Laser manufacturing surface roughness.

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In previous paper, turning with environment-friendly cooling method using water evaporation was investigated for the earth. In the turning using water evaporation, the tool life was 2 times of the dry cutting. Surface roughness of the machined work piece using this cooling was equal to that of dry cutting. Cylindricity of the machined work piece using this cooling was one third of that of dry cutting. In this report, in the cutting with environment-friendly cooling using water evaporation, influence of cutting condition, work piece material and tip material was investigated. It is concluded from the results that ; (1)Environment-friendly cooling using water evaporation was effective at the time of cutting with large heat generation such as heavy or middle cutting. (2) In case of cutting of a work piece with large specific cutting force, as area of tip surface is a little, cooling capacity of this method using water evaporation wasn't sufficient. (3) In case of tip with heat resisting material such as cermet or ceramic, this method using water evaporation was ineffective.

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Diamond-like carbon (DLC) film has outstanding properties, such as high hardness, chemical resistance, and low friction coefficient under various conditions ; however, DLC films deposited by conventional methods still have a problem in low optical transmittance due to sp² carbons remaining in the film. This paper describes sputtering deposition of DLC films using a sintered diamond target, which consist of sp³ carbons. Mechanical and optical properties of the DLC films were discussed in comparison with the DLC films prepared using a graphite target, and it was found that not only the hardness but also the transmittance of the DLC film grown from a sintered diamond target were higher than that for a film grown from a graphite target. These results indicate that the target material has the strong effect on the properties of DLC films, and high-quality DLC films can be prepared using a sintered diamond target.

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Ball bar system is a useful tool for checking the machine tool performance. However, its total accuracy including dynamic performance have not checked and its method also does not established yet. This paper describes the methodology of the total calibration of double ball bar especially to calibrate its dynamic performance. The proposed system can check the transient performance of the ball bar system with software data treatment systems. The developed system can generate feed in and feed out motion for software trigger mode by the electro-magnetic actuator. This system can evaluate the ball bar system's total performance that include mechanical properties and software characteristics including digital sampling performance. The developed system will be useful to improve conventional systems.

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Every kind of consumer products is deployed from market-in stage through growing-up stage to maturated stage by gradually shifting its appealing features from fundamental functions to supplemental value-addition over its life stages. This paper proposes a design assessment method for the product definition of a new product, which is an essential key toward market success of consumer products under the today's rapid and competitive product cycle, based on existing products along with such life stages. Since a series of products over life stages share the underlying design concepts, the contents of their quality-function-deployment tables must be partially shared with each other, while the definition of customer attributes is shifted due to their growth and maturation in market. Based on this observation, an assessment method is organized based on quality function deployment and cost-worth graph to facilitate establishment of product definition. Its validity and promise is ascertained through analyzing design changes across three vacuum cleaners in different life stages.

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To realize a multiobjective satisfactory design method for actual product designs, we investigated expression of objective functions, search method of solutions and identification of sensitivity coefficients. We introduce an identification method of technical but non-theoretical objective functions by trial productions and the regression analysis. The regression analysis of evaluated values of the products yields orthogonal polynomials of the functions. Studies on accuracy of the method in case of theoretical functions indicate the ratio of influential factors involved in the productions should be more than 50% and they also prove the number of products or levels and individual or combined productions are not important.

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