The structure-borne sound in bending waves has been studied by many researchers. However, the majority of those studies have aimed at achievement of only measurement or calculation of structure-borne power. This paper presents a new determination method of an excitation force point for noise reduction. The method is based on modal expansions of structural intensity for controlling vibration energy flow. The modal expansions are expressed as the superposition of modal terms determined by the product of the weight coefficients and the product of two spatial derivatives of natural mode shapes, which is referred to as the “cross-modal functions”. The weight coefficients depend on the excitation condition, and the cross-modal functions only depend on mode shapes. Therefore, if excitation point would be changed, we can control weight coefficients. Increasing a weight coefficient means to excite strongly the cross-modal function corresponded to the coefficient. As a result, the distribution of structural intensity can be modified. In this paper, we propose the method for determining excitation location which excites a non power transmission typed cross-modal function, which have no power transmission and relate to low noise. The numerical application results present a validity of the method.

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In this paper, we study periodic energy transfer in multiple vibro-impact oscillators under proportional viscous damping by using wave algorithm. Internal resonance frequency is obtained by the condition that some off-diagonal elements become to 0 in state transition matrix. Under equivalent modal damping rate, we derive the condition of periodic damped and periodic energy transfer that contains sub-harmonic resonance which depends on mass ratio between the impact and non-impact small oscillators. Under non-equivalent modal damping rate, modulation of the frequency in imperfect damped energy transfer is observed. We obtain a state transition matrix of non-equivalent modal damping rate as the perturbation of that in equivalent. The modulation of periodic damped energy transfer depends on the decay of the modal damping rate in the small impact oscillator.

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In this research, a new no backlash drive control system is proposed, and the basic principle and the analysis of the drive system, the control design method, the simulation, and the position control experimental results were described. The no backlash drive control system consists of common reduction gear, a motor, servo amplifier, and a control device, which drives one load, combining a pair of motors as for a plus direction motor and a minus one, and cancels a backlash. When driving the load to a plus direction, the torque of a plus direction motor is made to increase ,in which a plus direction motor and a minus one add equal offset torque to the load and, hold the load axis. At this time, a minus direction motor adds fixed torque in the inversion direction, forces a cog on the load axis, and cancels the backlash. It verified in the simulation that the responsibility could be improved by feeding back the average value of a plus direction motor and a minus one, as the position and velocity feedback signal, in consideration with the natural vibration of reverse phase being superposed. In the experiments, the backlash has been cancelled by this control system.

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This paper describes an active control system intended to minimize the vertical vibrations transferred from the vehicle seat to the head. This system controls mechanical properties effectively such as the spring constants and damping coefficients of the seat cushion by using an optimized algorithm that comprises vibration analysis and an optimization method. To estimate an efficient optimized algorithm, we investigate reduction rates of the vertical vibrations on the head using a vibration analysis based on a model for the seat-occupant system when the mechanical properties are controlled in a part of seat cushion. These results showed relationships between the reduction rates and the mechanical properties of the each seat cushion optimized at frequency band. In conclusion, the effective optimized algorithm using these relationships enable to reduce the vertical vibrations on the head while reducing the number of seat cushion control.

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We proposed a method to suppress the first mode bending vibration in a carbody of railway vehicle by using a damping control system of primary vertical dampers. The results of running tests using actual Shinkansen vehicles showed that the control system can effectively reduce the power spectral density (PSD) of accelerations of the carbody floor. On the other hand, the previous researches indicated that on-board passengers make a difference to the bending vibration of the carbody. Therefore, in this study, to confirm the efficacy of the control system regardless existence of passengers, we carried out numerical simulations using a vehicle model combined with passenger models and excitation tests on rolling stock testing plant with/without passengers. As the result, we could make clear the influence of on-board passengers to the bending vibration by using the model. Furthermore, by using the same control parameters, we verified that the system could obtain the excellent performance of vibration suppression regardless existence of passengers.

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This study examines the braking assistance system for train drivers when stopping at a station to prevent the drivers from overrunning. The conventional assistance system informed the driver visually of a predicted stopping position based on present vehicle velocity and deceleration. The driver with the conventional assistance system made the vehicle stop with large deceleration because the conventional assistance system calculated the predicted stopping position by considering the constant deceleration. The assistance system this study proposes considers the deceleration with constant jerk, i.e. the deceleration gradually decreases. Train-driving simulator experiments are examined with several subjects who are required train driving with the mental calculation which assumes the mental workload. Subjects with the proposed assistance system can operate the brake handle smoothly, and make the vehicle stop with small deceleration. Subjects with the conventional assistance system, on the other hand, cannot release the brake handle, and make the vehicle stop with large deceleration.

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This paper proposes a method of a non-contact experimental vibration analysis for underwater structures by pulsed-laser ablation. The impact testing with impulse hammer is used widely for vibration analysis due to the simplicity of the apparatus. However, the impact testing has limitations in use in underwater condition because of contact method by the experimenter. The proposed method yields the frequency response functions by applying a pulsed-laser-ablation excitation force to the structure and measuring the output using a laser Doppler vibrometer. Since the direction, strength and effective duration of the pulsed-laser-ablation force are essentially constant, this force can be calibrated by measuring these properties in advance. Therefore input-detection-free frequency response function measurements can be realized. The method is validated by comparing frequency response functions obtained using laser excitation with FEM. Additionally, the frequency response function obtained in underwater conditions shows that the natural frequency decreases and the amplitude is attenuated by comparing with frequency response function in air conditions.

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Pad type compressive force sensor suitable for high speed impact force measurement is developed. A piezoelectric film is sandwiched by a pair of the thin metal sheets. The electric wire is connected to the metal sheets which are the electrode of piezoelectric film. The whole of the sensor is covered by thin resin sheet, and layer components inside the sensor are fixed together in one body. A sensor is about 1mm in thickness and it can be made in the various shape according to the purpose of use. Several pad sensors are made for trial purpose, and the performance are examined through experiments by applying fluctuating loads and impact loads. Finally, the pad sensor is applied to the impact force measurement of golf ball shot by setting up the sensor to No5 and No9 golf irons.

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Future robotic systems intended to be used for domestic housekeeping or elderly care should flexibly adapt to the environment which is uncertain and may fluctuate. However, the current robot systems for industrial domain can operate only in the limited environment (well arranged and very little uncertainty) and require the special knowledge such as teaching-pendant and robot programming of the robot motion instructors. Obviously such requirements are not appropriate for home-use robots. This paper proposes a new method for in-situ robot motion modification by Hand-Guiding instruction. With the proposed method, a human demonstrator can intuitively modify the robot motion during its operation to adapt to environmental changes. Some daily domestic tasks are actually tried by using a lightweight pneumatic robot arm and the experimental results show the effectiveness of the proposed method.

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There is an increasing demand on developing autonomous mobile robots for field survey activities to save working hours, work force and workers' health. We have chosen a commercially available ATV as the base of the autonomous vehicle and developed several devices for throttle control, brake control, and speed measurement. In this paper, a wire winding steering system is constructed and verified. The steering system consists of two wire winding devices. Each wire is attached to either side of the handlebar and provides a tension to rotate the handle toward one direction. The mechanism has a property of antagonism like the human muscle and skeleton structure. To control the steering angle and compliance properly and cooperatively, the measurement of the tension is necessary. In this paper, we also construct tension observer and verify the performance through experiments. As a result, we reached a conclusion that tension observer is able to estimate wire tension with a small error.

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This paper discusses the deformation of yellow spot of retina by applying a compulsory eye pressure increase through a probe with force gauge. By using the caribration data between the eye pressure and the force gauge, we impart the force corresponding to 50 [mmHg] of eye pressure to eyelid. Through OCT data before and after compulsory eye pressure increase, we analyze the deformation of yellow spot for three differnt layers. An interesting observation is that yellow spot suffered by glaucoma has thinner layer and smaller deformation than that of normal subjects, especially the characteristic is enhanced in both the surface and bottom layers, while it is not in the middle layer.

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Lumbago occurs when load causes malformation of the flexible intervertebral disks of the lumbar vertebrae. The conventional method of measuring load on the intervertebral disk is an invasive method in which the internal pressure of the intervertebral disk is measured by directly inserting an electrode. In this study, intervertebral disk load is derived indirectly by the noninvasive estimation method that uses three-dimensional motion analysis system and signal processing to estimate the shape of the lumbar vertebrae. Specific estimation method is shown as follows. First, vertebra is assumed to a rigid body. Next, lumbar vertebrae are approximated with an arc using 3-D positional coordinates. Finally, average of the intervertebral gap is estimated. Accordingly, because the proposed method only entails applying markers to the surface of the back and taking pictures with cameras, it is safe and does not require surgical procedures. Furthermore, this method allows estimation of intervertebral disk load in a moving subject. In this paper, the proposed method is described in detail. And an experiment in which intervertebral disk load is estimated from stationary postures is executed. Moreover the proposed method is compared with the conventional method. As a results, the experiment shows that the proposed method is effective in that the magnitude correlation tendencies of intervertebral disk load estimated with the proposed method are qualitatively consistent with the tendencies calculated from actual measurements of internal pressure.

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Recently, biped robots are flourished all over the world. Japan, as a leading country of biped robots, plans to send them into the moon. The project is greatly magnificent, but there are lots of problems to operate biped robots on lunar surface. One of the biggest problems is the difference of gravity between the moon and the earth. Therefore, it is necessary to develop control methods concerning the reduced gravity. This paper proposes a novel control method to generate gait under variable gravity. Previous study shows a method to generate gait based on passive dynamic walking. Proposed method expands the previous study and enables to control robots' step length and velocity on any slope angle under variable gravity. The concept of the proposed method is to generate gait based on natural relativities of passive dynamic walking: the step length depends on the slope angle and the velocity depends on the gravity. To generate control inputs, we derive the passive dynamic walking that corresponds to the desired gait in terms of step length and velocity. Then we apply this referential passive dynamic walking to previous method and we obtain control inputs. With proposed method, it is shown that simulation results under variable gravity conform to the desired gait.

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In this paper, a novel nonlinear observer for caster wheel odometers is proposed which estimates the translational and the rotational velocities of the mobile robots. The proposed method is shown to be applicable to generic mechanism of caster wheel odometers. In addition, for the extended linearized system with respect to the estimation error, exponential convergence of the estimation error is proved, which guarantees that the proposed observer is robust against measurement noise and unmodeled dynamics. The advantage over the conventional approximated differentiator is shown in numerical simulation, which indicates that the estimation error is much smaller and less sensitive to both the external disturbance and the motion of the vehicle. Finally, an experiment on velocity tracking control is conducted for a leg / wheel omnidirectional mobile robot to show that the tracking performance can be obviously improved by the proposed nonlinear observer.

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In this study, we design an average facial color image avatar called FaceAvatar, and develop the system for the analysis by synthesis of affect display by dynamic facial color and expression. More specifically, FaceAvatar is designed by applying texture mapping to the average facial color image in a 3D wire-frame model that estimates various feature points on the facial surface of the average facial color image. The developed system enables laughing operation of FaceAvatar through the use of a computer keyboard. Further, the proposed dynamic model of facial color and expression under laughing emotion are analyzed synthetically by using the system. The effectiveness of the system for the analysis by synthesis is demonstrated by sensory evaluation.

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For the clarification of the overturning behavior of railway vehicle exposed to strong cross wind, several experiments were done to study the effect of wind velocity and wind direction on the wheel unloading ratio. In this paper, the results of the experiment at a line in the Kanto region are described. In this line, strong wind is often observed, and various types of train are operated. To get useful knowledge about the improvement of the critical wind speed of vehicle overturning, data were analyzed in terms of the vehicle cross-sectional shape. Results of the experiment show that vehicle specifications, such as a car weight, or a bogie suspension are little effective for overturning, if there are no difference about the cross-sectional shape. Analyzed results of the experiment also show that depending on the cross-sectional shape, the behavior of wheel unloading ratio by strong wind is different. These results suggest the possibility of the superiority of round shape roof for improving the performance against overturning.

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In this paper, a new mapping method with Data Envelopment Analysis (DEA) is proposed. The objective of the mapping with DEA is to grasp the similarities among the Decision Making Units (DMUs). In order to grasp the similarities among the DMUs, a critical line should be determined. The critical line is automatically generated by the proposed method. In the proposed method, the Extended CCR model is employed at first. Each DMU is mapped onto the efficient frontier generated. As the efficient frontier by the Extended CCR model is different from each DMU, non-smooth critical line can be obtained. To obtain a smooth critical line, an objective function of the Lagrange multipliers is minimized. All DMUs are mapped onto this smooth critical line, and the similarities can be evaluated. DEA can handle multiple inputs/outputs, however it is difficult to grasp the similarities among the DMUs. To grasp the similarities, Principal Component Analysis (PCA) is applied for the visualization. When time series data is used, it is also possible to grasp both the similarities and the technical trends. In order to show the effectiveness of the proposed method, automobile data from 1995, 1999 and 2002 are used. It is easy to grasp both the similarities and the technical trends from the results.

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This paper proposes a novel approach to profile design of constant-diameter cam with a translating follower. The approach has some favorable features such as simple design calculation and easy programming, no requirement to numerically solve nonlinear equations, and thus can determine the cam profile together with the detailed data of radius of curvature and pressure angle precisely and conveniently. Moreover, two constraints for the design are also clarified in the paper. The first is that an opposite offset layout is necessary for both rollers if the centers of the rollers do not move along the same straight line. As the second constraint, the follower only can perform the period of displacement motion odd number times while one revolution of the cam and the motion in each period must be the same as well as the period range. The effectiveness and efficiency of the approach are sufficiently illustrated through two design examples of constant-diameter cam.

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A high expectation is placed on the introduction of Clean Energy Vehicle (CEV) to reduce CO2 emissions and energy consumption in the automotive sector. However, each CEV has its pros and cons. Therefore, the type and the number of CEV need to be considered before considering the way of introducing CEV. Many studies have been done on this topic, but their portfolios leave trucks and buses out of consideration. Also, past studies took energy security and infrastructure cost out of consideration. This study presents new optimization model which obtains optimal CEV portfolio of passenger car, truck, and bus in Japan, considering economy, CO2 emissions, and energy security. Simulation indicates that HEV, NGV, EV in passenger car and NGV, DHV in truck should be introduced, and especially NGV in truck is required in order to achieve the oil dependency rate designed by the government.

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The aim of this study was to examine the effect of job enrichment system in terms of brain activation by measuring EEG. Ten male students participated in both a assembly work of Lego blocks without any feedback information (No-feedback task) and a job enrichment which receives feedback information for the work progress and the faults in the assembly work (Feedback task). We measured EEG, ECG, Jikaku-sho Shirabe, NASA-TLX, and morale survey. The results were as follows: (1) In Feedback task, productivity was significantly boosted by increasing worker morale such as fun, enthusiasm, and sense of fulfillment and accomplishment. (2) Subjective ratings of dullness, boredom, frustration was significantly lower in Feedback task than in No-feedback task. (3) Heart rate significantly increased in Feedback task compared with in No-feedback task. (4) Alpha1 (8-10Hz) and alpha 2 (10-13Hz) waves related with sense of fun, fulfillment, and accomplishment in frontal and central areas increased in Feedback task compared with in No-feedback task. The results suggest that the job enrichment with feedback information had a positive effect on workers, and the effectiveness of job enrichment system was demonstrated by measuring of psychological parameters including EEG.

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An ultrasonic technique was applied for the measurement of bearing load of deep groove ball bearing operating under low rotational speed without the influence of temperature rise and vibration. Ultrasonic wave pulse entered from an angle probe attached to the outside of housing is partially reflected from the interface between housing and outer ring of the bearing. Reflection echo can be used for a measurement of the bearing load, because the intensity of echo depends on the local pressure related to the ball load. In this study, ultrasonic transmittance decided with the reflection echo height was employed as an index for the measurement of bearing load, and measurement was carried out with using the relationship between load and transmittance calibrated under extremely low rotational speed. As a result, it became clear that required calibration curve was obtained by the measurement of transmittance for two normal loads having a difference moderately, even though a direction of load was changed. The potential of in-situ observation of bearing load using ultrasonic technique was confirmed, since the bearing load, its direction and vertical / horizontal component (which were estimated from echo height and calibration curve) agreed with the actual value of them which were applied to the bearing.

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Reciprocating tests were performed to clarify effects of frequency and stroke on friction in boundary and mixed lubrication. With increase in stroke under constant frequency in boundary lubrication, coefficient of friction was observed to increase, which, however, turned to decrease with promotion of oxidation. Specific wear rate varied in accordance with changes in friction. In the next stage, to specify respective effects of frequency and stroke on friction, reciprocating tests were continued by changing frequency and stroke under a constant sliding velocity in boundary and mixed lubrication. There were two regimes of changes in friction in boundary lubrication, depending on whether oxidation was promoted or not. In severe sliding conditions where little oxidation was observed, a combination of higher frequency and smaller stroke produced rougher surfaces, resulting in higher friction. With improved lubricating conditions, however, higher frequency promoted oxidation, lowering friction, whereas in mixed lubrication, a combination of lower frequency and larger stroke contributed to oil film formation, which showed lower friction than that at a combination of higher frequency and smaller stroke.

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The electric sliding contacts are widely used in electrical components such as for automobiles. The purpose of the present study is to improve the performance characteristics of the electric sliding contacts and to extend their lifetime by applying the porous materials used for conventional sintered metal bearings to the surface materials of the sliding contacts. The effects of the permeability of porous materials on the frictional characteristics and the electrical conductivity have been investigated theoretically and experimentally. The sliding contacts used in the present study consist of a nonporous rider (stator) having spherical surface and a rotating porous disk (slider). The experimental analysis is conducted with a pin-on-disk friction tester to measure the frictional force and the contact voltage between the sliding contacts. The oil-film force and the frictional force between the rider and the rotating disk are also calculated by simultaneously solving the modified Reynolds equation and the Laplace equation derived from Darcy's law. The numerical results qualitatively agree with the experimental results. These results show that an increase in the permeability of the porous materials extends the operating conditions under the continuous metal contact to a higher value of the bearing characteristic number S defined by ηU₀L(B/L)/W (η: oil viscosity, U₀: sliding speed, L: length of rider in direction of motion, B: width of rider, W: applied load), and it also decreases the frictional force at the maximum S at which the rider could contact with the disk surface. This suggests that the porous materials yield a lower frictional loss and thereby show a possibility for a longer lifetime.

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The conical involute gears have been applied to automotive parts such as FR-4WD transfer. To apply for automobile, high capacity and higher quietness are required. However the tooth contact of conical gear pair is point contact, so the large ease off happens even though each tooth surface has no manufacture error. Also the tooth depth and thickness of conical involute gears change along the lead direction. These characteristics have to be considered for the tooth mesh analysis. This paper proposes a simulation method for calculating the relative tooth surface form that is called ease-off. It also describes an improved method of estimating the tooth mesh compliance that takes into account the change of tooth shape. With these methods, we can accurately analyze the transmission error of a conical gear pair as well as a cylindrical gear pair.

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Brake pads are phenolic resin composites which contain many ingredients such as metal fibers, inorganic fillers, organic fillers, and so on. As a basic study for the improvement of brake pad wear, the influence of fine metal oxide powder on pad wear characteristics was investigated, using pad samples with simplified formulation containing different types of metal oxide. These test samples were rubbed against the cast iron using twin-ring tribometer. Wear test results showed the pad wear varied with the type of metal oxides. Low wear was shown with the addition of metal oxides which were hardly reduced. In other words, pad wear was related to the degree of difficulty in reduction of metal oxide. This indicates the reductive atmosphere was formed at friction interface which was brought by the decomposition of the phenolic resin. Therefore, pad wear depended on the difficulty in reduction of metal oxide in the phenolic resin composites.

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In the 21^st century, as it is important to produce products with care for protecting the earth, a producer must be careful to conserve energy, save resources and reduce waste which pollutes environment. On the other hand, in case of a machine tool, much lubricating oil was used for smooth drive and positioning with high accuracy on the slide of most machine tools. The oil is wasted and scrapped in the natural world. This is large problem for protecting the earth. Therefore the grease lubrication with maintenance free for long term on the slide of a machine tool is developed and evaluated. The polymer (=Polyisobutylene PIB) was firstly added for high following property in the grease, then the optimum composition was decided for permanent lubrication. Then the W-rollers was developed for attracting the grease round the slider of the machine tool till the machine life. Lubrication property on the small machine tool using the W-rollers and the grease was evaluated in experiment. It is concluded from the results that; (1) Coefficient of friction regarding the grease with 3 % PIB was very small (<0.1) and its following property was very large, (2) W-rollers were very effective to attract the grease round the slider of the machine tool, (3) The slider using the permanet lubrication is moving with nice condition without maintenance, (4) The permanent lubrication was economical and eco-friendly.

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In the 21^st century, various kinds of materials are being used for high quality, and high confidence in various purposes. The establishments of optimum cutting condition for those materials are also being demanded for high productivity. On the other side, there exist many resonance frequencies for a machine tool. When a compulsory vibration of a machine tool congregates to the resonance frequency, extremely high vibration occurs on the machine tool structure and the geometrical accuracy of the work-piece also becomes lowered. For this condition, other cutting condition must be selected outside the range of the resonance frequency. Therefore, the technique for controlling resonance frequency on a machine tool was developed for establishment of optimum cutting condition. Resonance frequency can be controlled by changing stiffness and appearance density of a machine tool. In particularly, resonance frequency under 100Hz has very large influence on the vibration of the machine and thus for the accuracy of the product. Therefore, simple and rational reinforced structure for high stiffness, and lightweight structure for low density were considered for controlling of resonance frequencies less than 100Hz. Injection of water was used for creating high density in a machine tool structure. Moreover, the positions of supports under the machine tool were also changed for controlling vibration. The experiments were done using the techniques mentioned above. Form the results, it is concluded that, (1) The technique for controlling resonance frequency on a machine tool was effective for cutting with optimum machining condition, (2) Reinforced structure, lightweight structure, injection of water and changing position of supports were very effective for controlling resonance frequency.

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Recently, mirror-like surface on a mold and a die was required for adding high quality on the most products. Particularly, as the processing of the mirror-like surface on the mold or the die with small and complex shape is difficult, the processing is performed a very long time by polishing of the skilled worker. Automatic polishing for the products is very difficult. Therefore the polishing on a small mold or a die with complex shape was developed and evaluated. The small polishing tool was firstly developed for the experiment. A small ball head of epoxy resin is bonded on the tip of a thin pipe and diamond grain is included in the ball. Diameter of the ball is less than 1.0 mm. The process for making the head, the polishing method and the optimum polishing condition are investigated in several experiments. The polishing tool is installed in the spindle of the CNC milling machine. This system was evaluated for processing the mirror-like surface on the small parts with complex shape. It is concluded from the results that the tool and the polishing system developed was effective for processing the mirror-like on the surface of the small parts with complex shape, and optimum polishing condition was also cleared.

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This paper describes the testing method for five-axis machining centers using three-dimensional circular interpolation movement equivalent to the cone-frustum cutting. It is assumed in the simulation that a ball bar system is used as a measuring device that can freely moves in 3D space. The ratio of a measurement value by the ball bar and a real error of each axis is defined as a sensitivity coefficient of axis. The sensitivity coefficient of each axis was calculated changing the apex angle and the center location of virtual cone-frustum. The 3D circular movements are simulated, and the effect of the pitch errors of the axes of rotation was investigated by changing the sensitive direction of the ball bar. From the view point of sensitivity coefficient, it is pointed out that if the measurement is conducted by the ball bar which is parallel to the bottom of a cone-frustum whose center is set away from the center line of the axis of rotation, it is possible to measure the movement errors of five axes.

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This paper describes the effect of the run-out on the tool wear and the cutting force in micro ball end milling. The cutting tests were carried out with the micro ball end mill that has a geometry consisting of two flutes and the radius of 200 μm. The run-out was generated by inserting the micro ball end mill and the shim in the collet. The spindle speed was fixed at a constant value of 15000 min^-1 minimized the repeatable run-out and the non-repeatable run-out. When the thickness of shim was varied in 0.01, 0.03, and 0.05 mm, the run-out was 6, 20, and 38 μm respectively. As a result, the difference of maximum flank wear in two flutes increased with an increase in the run-out. The difference of the maximum flank wear in two flutes increased near the center of the micro ball end mill. The average cutting force was not dependent on the run-out, however, the difference of the cutting force acting on two flutes increased with an increase in the run-out.

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Multi-tasking machine tool has a variety of machining functions, which may lead to the reduction in machining time and the machining with high quality, and they have the growing availability. On the other hand, the use of multi-tasking machine tool causes the long process planning due to the functional complexity. There are some CAM systems for multi-tasking machine tool, however they need long working time caused by the mannual allocation of parts to generate tool paths. Therefore, the study proposes the rationalization of the process planning by extracting the machining feature in consideratinf with turning and milling from targeted shape to be machined and by selecting suitable machining method and scheduling machining order automatically. As a result, it is expected to reduce the working time on CAM system, using output data by proposed system. Applying the system to several product shapes containig both turning feature and milling feature, it is confirmmed that NC data can be obtained for each shape without any problem.

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In glass polishing process, cerium oxide (CeO₂) abrasives are widely used because both high removal rate and high-quality surface finish can be easily obtained. The metal component cerium (Ce), however, is one of the rare earth elements. Recently, because of the problems of the skyrocketing price increase and the supply risk of the CeO₂, the development on alternative materials/technologies and reducing consumption of cerium oxide abrasives have been strongly requested. In response to the requests, the authors have proposed the zirconium oxide (ZrO₂) abrasive as the alternative abrasive of the cerium oxide. Even under the low slurry supply rate, a larger number of effective abrasives between the work and pad can realize the better polishing characteristics. Two methods have been proposed to increase the number of effective abrasives on the polishing pad. The first method is to use the cohesive abrasives during polishing and the second is increasing stagnation of the abrasives during processing. Based on these results, it has been confirmed that the zirconium oxide abrasives have the possibility as alternative abrasive of the cerium oxide for glass polishing. This paper describes that the results of the series of tests proved high polishing characteristics in terms of the surface roughness and removal rate for soda-lime glass.

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