Numerical analysis method of transient forced vibration responses of thick rotating shells of revolution is developed. The method can consider the anisotropic laminated layers and the effects of prestresses such as the in-plane compression stress, internal pressure and torsional shear stress. Finite element method is applied using truncated conical shell element based on the first-order shear deformation theory, and the finite strain is considered to execute the non-linear analysis of the quasi-static displacements due to the rotation and prestresses except for the case of internal pressure. Transient responses of a laminated truncated conical shell and a partial spherical shell subjected to concentrated step and half-wave sinusoidal shock forces are calculated and compared with the previous results based on the classical shell theory. Finally, the effects of three kinds of prestresses are systematically examined by using a truncated conical shell model with the both ends clamped.

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The vibrational behavior of continuous systems such as beams, plates and circular cylindrical shells subjected to random parametric excitations is examined mainly from the viewpoint of possibility of unstable phenomena. The vibrational responses of those continuous systems are analyzed by means of simulation method using random sample functions of trigonometric series generated by random numbers. It turned out that unstable phenomena occur even for the cases in which random parametric excitation inputs have the fairly wide-band power spectra whose dominant frequencies deviate from, for example, the twice of the natural frequencies of continuous sytems. Besides, for such continuous systems as plates or shells which have the high frequency distribution density, unstable vibrations are generated concurrently in multi-vibrational modes. Finally, the experiment was carried out for a simply-supported beam subjected to the narrow-band random parametric excitation and it was ascertained that unstable vibrations really occur, and further the unstable figure domain made by the simulation analysis showed fairly good agreement with the experimental results.

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High-speed operation is required for industrial machines equipped with belt driving systems. The driving belt is, however, subject to a speed limitation due to the occurrence of bending mode resonance vibration caused by machinery error, e.g., pulley eccentricity. In order to reduce this resonance vibration, a parametric excitation method provided by belt tension fluctuation is proposed, based upon the concept of open loop vibration control theory. The belt driving systems require various setup angles. We tested the resonance vibration control for many inclined types of belt layouts along the horizontal to vertical ways. Parameter selection for optimum vibration control of inclined axially moving belts is verified through experimental data.

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In order to realize the practical use of permanent magnets that have a high coercive force and high residual magnetic flux density, we propose the use the magnet-spring, which can generate the force of 0.67 MPa that happens with the magnetic flux density of 1.3T. The linear characteristics of the metal spring and the non-linear characteristics of the magnet-spring are joined to create a combination spring which has linear characteristics when the spring constant is in a quasi-zero state, under normal conditions of use, but overall is a non-linear spring system. In the magnet-spring, rare-earth magnets are faced so as to repel each other ; it is a vibration control technology that is comprised of repulsive forces created under relative motion, attractive forces, the flux control created by electro-magnetic induction, and the magnetic field gradient. We now offer this report on new characteristics of disturbance cancellation that achieve a non-resonance condition via passive control using the combination spring.

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This paper deals with rocking response behavior of rigid block structure subjected to horizontal excitation. A strict consideration of impact and friction between block and base is essential to identify the system parameters because the impact motion and sliding motion were influenced greatly by the rocking behavior. Therefore, not only restitution coefficient between block and base but also kinetic friction coefficient between those should be included in the modeling of rocking system. The program was developed to be able to simulate the responses of block subjected to simultaneous horizontal sinusodial excitations. By using this program, rocking responses were numerically calculated by the nonlinear equations for rocking system. From the results of response simulation and experiment the following results were obtained, the rocking responses are affected with impact motion due to restitution and friction and provide very complex behavior, the toppling condition of block is also influenced on the impact motion, and so on.

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The virtual vibration simulator using a part of the system is utilized to experience the vibration for bodily sensation under actual operating condition. In order to evaluate the effects of structural modification on the virtual vibration simulator, a new method is so developed as to predict the modified system frequency response function based on the hybrid component of the part and FE model for modification part together with the component of the rest of system. After being verified by simple structure, the method is applied to a steering of truck to generate the vibration under operating condition before and after structural modification, which is realized by three exciters.

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In this paper, it was analytically made clear that general solutions for the impact oscillator systems have accurate recursive feedback structural properties. First, general solutions previously obtained in terms of self-reference form was replaced by those which do not have explicit terms of impact velocity. As a result of this procedure, general solutions in the form of "reference value decomposition" was achieved in which explicit expression of the equation was obtained by taking the impact time as only parameter. Secondly, this formulation was furthermore developed by proposing the analytical procedure for getting "general solutions of recurrence form" which can lead the solutions expressed by the impact recurrence. From this formulation, it was exactly clarified that these solutions have recursive feedback structural property with respect to the impact. Finally, through the formulation proposed in this examination, a kind of "binary-tree structure" can be recognized in the linear system transform from the velocity domain into the time domain when we get the pseudo-feedback response solutions.

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Leakage-flow-induced vibration was discussed for a one-dimensional, narrow, parallel passage in which a plate could vibrate in beam modes. A wave equation of plate displacement composed of first and second order wave equations, and a beam equation was derived. A method to estimate the linear stability of the plate was proposed, in which a spatial integration of the equations was done using the Runge-Kutta algorithm, and eigenvalues and eigenmodes were estimated to satisfy boundary conditions. The dispersion relation was investigated to clarify the basic characteristics of the waves. The mode was decomposed into six wave components, and the energy supplied to the wave components by the fluid force was estimated. It was suggested that there were at least two mechanisms. One was the phenomenon similar to interfacial instability of the thin liquid film flow. The other was the phenomenon that progressive wave on the plate was destabilized by the wave component expressed by a first order wave equation when the wave speed of the first order wave equation was faster than the wave speed on the plate.

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This paper describes a characteristic of fractal dimension measurement. The fractal dimensions are calculated from digital images based on a box-counting method. Three kinds of connections with contours are examined : the 4-nearest neighbor connection(4NN), the 8-nearest neghibor connection(8NN), and a dilated type(DT). The 4NN works very well for not only simple shapes of particles but also complicated ones. The other 8NN and DT cause greater magnitude of errors in lower resolutional images.

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This research deals with evaluation of electromagnetic force and torque acting on a permanent magnet(PM)above a high-T_c superconductor(HTSC)and discusses dynamics of a spinning PM freely levitated above a HTSC. Force and torque were evaluated experimentally as functions of both displacement and tilting angle of the PM. Experimental results show that the force and torque acting on the PM are almost equivalent to ones acting on a rotor supported by an overhung shaft with a frictionless bearing. By theoretical analysis based on the above evaluation of the force and torque, dynamical behavior of a spinning PM was examined. Predicted whirling and precession on the PM were observed in experiments of rotation.

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The Interference between operation-side and drive-side roll gap cotrol system arises in gagemeter control on rolling mill. It has become remarkable with high responsibility of roll gap control system. We have studied gagemeter control system with two asynchronous electrichydraulic servo systems, and found it is caused by the difffferences of their chacteristics, that is the diffrence of transfer functions between roll gap control systems in operation-side and drive-side.

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The purpose of the present investigation is to design an adaptive noise control muffler which has the most suitable location of secondary source. In the experiment, the distribution of sound pressure level in the muffler model has been measured by a sound visualization technique in order to obtain the maximum sound reduction by the minimum secondary sound under active control. The experimental results show that the target frequency could well be attenuated when the distance between the primary source and the secondary source is equal to the length eguivalent to one-half of the wave length of a target sound or its integral multiples.

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Structural-acoustic analysis was performed in order to reduce booming noise due to floor panel vibration in heavy duty truck cab. Usually a common cab is used for various truck configurations. Therefore, a robust cab design which allows reduction f booming noise under various cab excitation forces is deemed to be important. As a first step towards this goal, finite element model of a cab floor panel and bounday elment model of a cab cavity were created, and the good correlation of booming noise between the simulation and excitation test was confirmed. In order to propose a rubust cab design, Taguchi Method was applied for a design parameter sstudy of the floor structure. This paper describes the method which can evaluate the effect of design parameters quantitatively with the ratio of main effect variance and interaction variance between main effect and excitation frequency. The parameters for noise reduction over a wide frequency range and paramers for noise reduction at a specified frequency can be discriminated with this method.

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In the previous paper, the authors proposed a new mass measuring method under vibration-like moving conditions. The mass measuring system consists of a weighing load cell and several compensation load cells called as dummy load cell. The dummy load cells are used for getting the information on the position of mass center of the weighed object and on the vibration-like moving conditions. However, to practical use, the influence of zero drifts of the load cell's outputs caused by the change of temperature, humidity, etc., on the measured value must be considered. But it is not so easy as we do it under the static condition. In this paper, a new method is proposed to eliminate the influence of the zero drifts under vibration-like moving conditions. It is also verified through the experiment that the new method is effective to improve the measuring accuracy.

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Phase difference between the object beam reflected from the target surfaces and the reference beam can be calculated from the brightness data of the interference fringe pattern by phase shigting method. The relative phase difference of a target surface relative to the reference one can also be obtained, but it is discontinuous since amplitude is multi-folded within the region from -π to +π. The concatenation to get the continuous relative phase difference corresponeding to the form deviation between two surfaces is therefore necessary. But it is not easy to concatenate the discontinuous phase difference data into the continuous one, especially when the density of interference fringe is thick and noises are largely contained in the image. When a manual concatenating procedure is used to realize the continuous pattern, the amount of processing times for it is tremendous. In this report, a new automatic method for concatenating phase differences is reported, and taking gear tooth flanks for a sample of target surface, the result of automatical concatenation of relative phase differences corresponding to the form deviation of tooth flank of cylindrical involute gears is shown.

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Chang and Peng proposed a disign procedure of state-feedback systems that guarantees a certain level of linear-quadratic cost for all admissible perturbations. This is called guaranteed cost control. But they considered the case when an input matrix has special perturbations and guaranteed the existence of a controller only for a restricted class of sytems. This paper deals with the case when an input matrix has more general perturbations. Firstly, a suffcient condition for robust stabilization is given. Secondly, in contrast to Chang and Peng method, on the basis of a linear upper bound, it is shown that there exists a controller under some reasonable assumptions.

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The active-passive hybrid electrical circuit with piezoelectric elements was investigated to suppress the vibration of beam. In order to apply passive vibration control and actie vibration control on the beam simultaneously, the concurrent sensing and actuating piezoelectric elements were used. For the passive control, the optimal resistance was used which have the advantage of stable, fail-safe, without power requirement. For active control, the velocity feedback control was used. Based on the hybrid control method, the passive control circuit and the active control circuit can be combined on the same control circuit. Due to the optimal resistance in the hybrid control circuit, the system must have the phase lag. To improve the system performance, a phase-lead compensator was employed. This paper demonstrated theoretically and experimentally that the hybrid control has the advantages of both passive and active control systems.

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This paper deals with a design method for the dynamic vibration absorber which consists of a mass and a carbonblack filled rubber vulcanizate. A main system with the rubber dynamic vibration absorber was analyzed, considering nonlinear dynamic properties possessed by the rubber vulcanizate. Frequency response functions of the system were derived in the form including the rubber geometry and a mass ratio as design parameters. An objective function was composed of the frequency response functions. Minimizing the objective function with respect to the parameters of the rubber geometry for given mass ratio, the optimal values were determined. From the consideration of the results, a new convenient method to determine the optimal values was derived. This method was examined by the experiments. As a result, the validity of the analysis method was verified, and the availability of the present design method for the suppression of vibration was confirmed.

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ER fluid is a kind of functional fluid. The ER fluids have a unique characteristic, which changes its fheology characteristic to apply the electric fields. The property of the actuator using ER fluid is different from conventional actuators such as DC or AC servomotors. In this study, we developed a new actuator using particle-type ER fluid, which is caled ER actuator. The developed actuator can produce two directional torques. We derived the simple models of the ER actuator from reference torque to output torque and velocity characteristics. Then we verified the validity of the models and control performance of the actuator by conducting the velocity and position control experiments.

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In order to realize positioning of nano-meter precision, it is important to eliminate friction and backlash from mechanical parts making relative sliding and/or rolling motion. This paper first describes the principle of an Air Bearing Lead Screw(ABLS)in which the lead screw surface is completely separated from the nut surface by the pressured air film. Then a positioning system comprised of ABLS, a table, an air guideway and air bearings used for supporting the screw shaft is introduced. The system is free from friction except that by DC motor brushes. The basic dynamic characteristics of the system are examined and some controllers are designed and implemented. Experimental results show that the system can position the table with the accuracy of a few nano-meters.

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To supply electric power uninteruptedly during the maintenance task of live power electric line, it is necessary to realize an autonomous control of 6-link electro-hydraulic manipulator for the safe maintenance task. However electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements and its parameter fluctuations are greater than those of an electrically driven manipulator. Therefore it is relatively difficult to realize autonomous assembly tasks particularly in the case of manipulating flexible objects. In this report, a discrete event control system is introduced for the assembly task of electric lines into sleeves as a typical task of live power electric lines. In the implemetation of a discrete event control system, a novel learning vector quantization neural network is proposed and applied to the insertion task. To apply the proposed discrete event control system to the electric lines and sleeves which are not used in the neural network learning, lerning data have been generated by using the fuzzy inference. By the experimental results of 2 types of electric lines and sleeves, the proposed discrete event control algorithm and neural network learning using the generation of learning data by the fuzzy inference are comfirmed very effective to the complex task such as the insertion of electric lines to sleeves.

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This paper describes a motion and vibration control method of a muulti-link flexible SCARA robot whose task is Point-to-Point motion. Because proposed optimal vibration control trajectory is a type of modified trapezoid velocity trajectory, the limitations of velocity and driving torque of each joint can easily be considered at the trajectory design. Equations of motion which are linearlized at the initial and final configurations are used as restrictions in the optimal control theory. Practical implementation of the feedforward and feedback control into an available velocity feedback circuit is also presented. Simulation and experimental results show significant vibration reduction effects of the proposed method. It is concluded that the nonlinear effects can be suppressed enough by velocity feedback control while they are not considered in trajectory design.

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Human brain mainly performs two kinds of information processes, intelligent process and KANSEI process. KANSEI is used for the sensory test or evaluation in various fields to estimate many things. It is however hard to evaluate ovjects using KANSEI, because KANSEI is including individual subjectivity, vagueness and many-sided. Besides KANSEI depends on time and situation. In this paper, we propose an expression method of KANSEI. This proposed method use self-tuning fuzzy inference on spline membership function to express individual KANSEI. To show the effectiveness of the proposed system, we applied this method to evaluation of ripeness of persimmons. This method will be available to various kinds of sensory evaluating systems.

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This study proposes a method of cooperation for legged robots with their bodies vibrating in walking. The effectiveness of the method is verified by experiment of cooperative transportation by two quadruped robots on some steps. The approach adopts a simple mechanical end-effector : the supporting part on which an objects is only placed. This end-effector needs neither actuating functin nor precise sensing function so that it is light and simple. The motion method is also simple : a rule-based method to compose a leader-follower system in which each robot autonomously decides its own motion according to the object configuration. The robots of this system do not communicate each other explicitly but estimate the motion satates of the othetr robot according to the force information of the object. This communication method enables robots and humans to work cooperatively.

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This paper describes a path planning method considering the data of assembly conditions, such as geometrical shape, displacement, uncertainty of the object position and so on. The uncertainty is an important factor for the success probability of the assembly task. Our proposed method represents the position error that comes from precision object shape and displacement error by Gaussian distribution, and estimates the success probability of an insert path by considering the relative position error distribution or the objects. Moreover we propose the uncertainty reduction motion(contact motion), and analyze the uncertainty that is derived after the contact. In this paper, as a simplified path planning of the assembly task, we define 2 strategies ; the insert without contact strategy and the insert with contact strategy and apply the proposed quantification method to determine the optimal path of each strategy for the planar peg-in-hole task.

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A biped locomotion robot generally has multi-degree of freedom and multi-actuated mechanism. Its walking motion is difficult to be performed because of many parameters to be design in order to keep the balance. Many researchers are however attracted by a biped locomoation robot because it has some advantages in location capability. The purpose of this research is to generate dynamical motion of the biped locomotion robot through the trial and error process like a human growth. In this paper, we propose a new hierarchical evolutionary algorithm to generate trajectories of all actuators in the biped locomotion robot. The hierarchical evolutionary algorithm consists of two layers, the higher one is the GA layer which minimizes the total energy of all actuators by selecting the intermadiate postures, and the lower one is the EP layer which optimizes intermidiate posture in the walking motion. The dynamical motion obtained through the computer simulation by the proposed algorithm is applied to the real biped locomotion robot successfully.

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This paper proposes a dead reckoning of a modular omnidirectional vehicle. Wheel units assembled in the vehicle are modularized on their mechanisms and controllers, so that we can easily tailor the vehicle to individual transfer applicatoins. Each of the wheel modules estimates the vehicle position based on the information of the odometry and gyro. The wheel modules exchange their local estimates. The local estimates are fused in a decentralized manner, and then the wheel modules can precisely identify the vehicle position under the conditions of wheel slips and changes of wheel radius. The dead reckoning algorithm is formulated based on the extended Kalman filter, and some fusion rules are incorporated into the algorithm to improve the accuracy of the dead reckoning. Simulation and experimental results show that our dead reckoning can provide better positioning accuracy than the conventional dead reckoning.

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This paper presents a placement time optimization method of chip mounter. Placement time varies for chip mouters where a PCB(printed circuit board)and tape feeder position are fixed, with parts placement sequence and tape feeder arrangement with same hardware performance. The problem definition is how to get the optimal parts placement sequence and tape feeder arrangement for minimum placement time about multi-head chip mounter. We propose a method using GA based on the Virus Theory of Evolution. In this approach, viruses are regarded as partial combinations and applied to genetic operations to improve the quality of solutions. The experimental results support efficiency of this method in comparison with a method using simple GA.

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In order to shorten the traveling time for passengers, it is more important to increase the speed on the curved sections than that on the straight secions of the railways. However, when the train passes along the curved section at high speed, it is uncomfortable for passengers because of the over centrifugal acceleration, when the effect of the cant of the rails cannot be suppressed. In this research, the experimental set-up "Over Centrifugal Acceleration Simulator" was developed, which simulated high-speed passing through curved sections indoors, and developed electric actuators for tilting using a stepping motor which is capable of accurate-positioning control without feedback control, instead of air cylinder or hydraulic actuator which is used by the pendulum car and the test car. By the experimental set-up, high-speed passing through curved sections was simulated and a control method for the electric tilting actuator was examined, i.e., feedforward control with the track data. Experiments were carried out under some conditions to verify the effectiveness of the control method of the tilting control with a stepping motor for good ride quality.

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There exists the case that bending vibration of railway carbody is caused by way of connecting elements of carbody and trucks, such as bolster anchors. To investigate these phenomena, the authors describe a new mathematical model in which the effect of the connecting elements on the vibration characteristics of railway vehicle are taken into consideration. The energy method is used to derive the equation of motion, and numerical calculations are carried out by using the proposed model. The riding comfort level L_T is evaluated numerically for several specification parameters concerning of carbody, trucks and their connecting elements. The numerical results show that L_T is largely improved when the bolster anchors and the center of gravity of truck are set nearby the center of wheelsets, and the effect of bolster anchor setting position on L_T is studied in many aspects. It is found that the rigidity of bolster anchor supporting rubber bush has important role on the vertical vibration induced through the connecting elements of carbody and trucks.

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In this study, we are concerned with the problem of improving manipulability of the electrically powered wheelchair, which is supposed to become popular in the aging societies like Japan. Almost all current-products is the market have joysticks as their controlling device, but they are not so easy to handle because the control systems equipped with those wheelchairs are usually very sensitive to the human manipulation. Another difficulty arises from the fact that the elderies are not so familiar with using joysticks to manipulate the wheelchairs. Against these difficulties, our aim is to provide an 'easy-to-manipulate'wheelchair. We first have carried out an experiment to understand the cause of the stress for users of the wheelchair during manipulation, by performing a spectral analysis of the Heart Rate Variability. Based on that result, we have found it effective to employ 'model following control scheme' for the control of the powered wheelchair. Finally, sensory testing has been done to show the validity.

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Conical involute gears used for marine transmissions are mostly helical conical involute gears. Besides these gears are not only intersecting axis gears but also nonintersecting-nonparallel axis gears. In this case the contact between tooth surfaces of a pair of gears is the point contact. Hence the tooth surface durability is generally small. In order to overcome this weak point, one of the authors invented a new type of conical gear, which is called "concave conical gear". Concave conical gear has higher tooth durability than the conventional conical involute gear. So we have already developed generating method of helical concave conical gear. In this paper, first the principal normal radii of the tooth surface generated by this method are expressed in terms of basic dimensions of gear and tool. The principal normal radii of test gears are measured. They are in good agreement with the theoretical ones. Secondly an allowable normal load of a pair of concave conical gear is obtained. Tooth bearing tests prove that the Heltzian contact ellipse is larger than that of the conventional conical gear. Thus it is proven that a designing method of a pair of concave conical gears is of practical use.

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It is very important to select proper material and heat treatment process for gear manufacturing. If the manufacturing conditions can be optimized in the design stage before catual trials, the total cost and lead-time can be reduced drastically. In this study, CAE systems have been developed for gear design and manufacturing by considering concurrent engineering approach. The systems are based on mathematical models for thermo-elasto-plastic behaviors during heat treatment. The objective is to predict microstructure and hardness distribution, as well as distortion and residual stresses quantitatively in design stage. A parameter such as a ratio of the fatigue strength and stresses occurred during engaging is proposed to evaluate gear strength. The fatigue strength can be estimated from calculated hardness and residual stresses considering non-metallic inclusions. In addition, a specific pre-and post-processor have been developed for user friendly operation. The calculated results of test pieces and practical gears are in good agreement with experimental ones. Finally, several examples have been reported to show that these CAE systems are useful for practical work.

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A method for measuring a screw-compressor rotor using a coordinate measuring machine(CMM)is proposed. The profile of the rotor is constituted by a number of profile curves that are smoothly connected with each other. The position of each connecting point can be expressed with its radius in cylindrical coordinates. Such a rotor tooth surface is measured with a CMM. During the measurement, the current curves should be identified and distinguished from the rest. To do this, we compare the radius with the distance between the measured point and the Z-axis in cylindrical coordinates. The essence of the method is as follows. First, the coordinates of a number of points on the surface are measured. Second, the probable rotor surface is estimated by the method of least squares, and the errors are determined. This paper explains in some detail methods for measurement of eccentricity, of errors due to the division of the tooth space, of profile errors, and of lead errors.

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When measuring the contact pressure of the joint, it is suggested that a method using ultrasonic waves has a marked feature, i.e., continuous applicability to the sliding or rotating joint without changing the state of contact. This paper reports a newly proposed parameter for the evaluation of contact pressure of cylindrical joint for spindle system of machine tools. Wavelet transform shows a noteworthy effect to extract the characteristics of joint. From the experimental results, the relationship between the radial run-off of spindle and the contact pressure of the joint in working condition has been discussed.

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In this study, a method to measure flank wears of peripheral cutting edges in end mills is proposed and a measuring equipment used in this method is developed. In order to measure the flank wear of spiral milling edges, a servo system consisting of a rotatory and a translatory axes is developed. An end mill is loaded on a collet chuck fixed to the rotatory axis and a CCD camera is set on the translatory axis. A monitoring of a minute part of tool edge geometries is carried out repeatedly after positioning the tool rotatory and translatory axes. Arranging the data obtained in such a way along tool edges, shapes of flank wears of whole cutting edges can be displayed in 2-dimensional diagram. As the results of measurements in the present method, flank wear geometrical shapes of peripheral cutting edges in end mills can be monitored, and it is confirmed that the variation of flank wear shapes in cutting process can be evaluated quantitatively.

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This study was carried out to investigate the profile characteristics of the indentation caused by an impact load on an oiled plate by a sphere. The materials of the anvil and the sphere were either SUS304 or SUJ2 to investigate the effects of the handness on the identation profile. Each indentation profile was measured by the three-dimensional stylus profilometer. The deformed volume of a plate was confirmed to be smaller than that of a sphere. The profile of the indentation showed a clear entrapment of the oil. The center of the indentation becomes deeper and sharper with increasing viscosity and pressure viscosity coefficient of oil. Clear edge was recognized around an indentation on a sphere in the case of an oiled impact. On the contrary, an ambiguous edge was recognized in the case of dry impact.

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Traction drives can be operated at low level of vibration and noise, so they are more suitable to high speed rotation than gears. Furthermore, they are useful in continuously variable transmission (CVT). The purpose of this paper is to develop a traction drive CVT that has high speed ratio and enables high speed rotation. In this study, a 3K-type planetary gear system is applied to a traction drive and the fundamental structure is examined. As a result, it is found that the cone can be balanced dynamically under a wide range of operating conditions, by optimizing the shape and layout of the cone. Furthermore, by reducing the effect of spin and the contact pressure, a CVT, which is capable for high speed rotation and long life, can be realized.

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In-process measurement of tool flank wear is very important for judgment of tool life with the object of running fully automated machine tools economically. The purpose of this study is to propose a new method of detecting tool flank wear by using characteristic values of dynamic cutting process during steady-state cutting in turning operation. In this report, a simple calculation model of dynamic thrust force was proposed to derive equations of characteristic values from it, and effectiveness of the equations was experimentally verified under many cutting conditions and excitation conditions of a workpiece system. As a result of the calculations and the experiments, we reached conclusions that two characteristic values of dynamic cutting process, standard deviation of dynamic thrust force normalized by the standard deviation of workpiece vibration displacement and coefficient of correlation between dynamic thrust force and vibration displacement, have the following properties. (i)The characteristic values remained almost constant with variation of feed rate of a cutting tool and vibration amplitude of a workpiece. (ii)On condition that vibration frequency of a workpiece is constant, the characteristic values obtained under different cutting speeds can be standardized by normalizing the width of flank wear to the cutting speed. (iii)Tendency of calculated characteristic values with increase of vibration frequency was partly disagree with that of experimental values.

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As regards the machining accuracy on deep drilling, straightness and roundness are generally discussed. The straightness error is caused by the axial deviation of hole, and the roundness error results from the occurrence of polygonal profile. The purpose of this study is to improve the roundness. To put it more concretely, we suggest the measuring system to evaluate hole profile in drilling process and the control system to correct hole profile error. The experimental result clearly shows that the measured profile of hole in drilling process by this measuring system and the measured profile by roundness measuring instrument after processing correspond. The usefulness of this corrective control system is verified by the comparison between the dieal profile that must be processed according to the programmed polygonal command and the profile of hole after polygonal control. Further, The experimental result with those systems shows that the roundness can be improved in drilling process.

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High quality assembly products are produced by a matching method in machining-assembly production systems. If we use an accuracy policy in the part selection policy which is applied to a ball-bearing manufacture, the part flow stagnates and buffer storage is necessary to increase the production rate. Furthermore, in some combinations of part machining error distributions buffer storage is not useful, and the production rate drops. In this paper, we study the optimum part selection policy which yields the maximum production rate using a Markov decision process. Next, we study the characteristics of the optimum policy, and show the effectiveness of the policy by comparing the production rates yielded in the systems by the policy and the accuracy policy. Finally, we discuss the flexibility of the optimum policy. From the analysis, it is presented that the optimum part selection policy is very effective to increase the production rate, and in every combination of part machining error distributions the policy yields the ideal maximum production rate.

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New architectures of manufacturing systems have been proposed aiming at realizing more flexible control structures of manufacturing systems which can cope with dynamic changes in volume and variety of products. They are so called as holonic manufacturing systems, autonomous distributed manufacturing systems, random manufacturing systems and bionic manufacturing systems. The objective of the present research is to develop an integrated process planning and scheduling system which is applicable to the holonic manufacturing systems. In the previous paper, procedures were proposed to recognize the machining features from the product model. A systematic method is proposed, in this paper, to select suitable machining sequences and sequences of machining equipment, by applying the genetic algorithm(GA)and the dynamic programming(DP)methods.

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The electrophotography system, such as a copier or a laser printer, requires multi-pole magnets for its magnetic development system. Some of the development magnets are produced by in-process magnetization of injection molded plastic magnet. The magnets produced by such a process have complex magnetization distribution. This distribution is reuired for the calculation of magnetic field but generally not known and difficult to express by a formula. Therefore it is necessary to estimate the magnetization distribution of the development magnets. In this paper, an estimation method consisting of two processes was proposed. The first process is an approximation of static magnetic field from the magnetic flux density distribution on the surface of the magnet by using magnetic dipole moments. The second process is a calculation of the magnetization distribution of the magnet which makes the magnetic field equivalent to the approximated magnetic field in the first process. This calculation is formulated as an optimization problem.

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