This paper dealt with the data-processing procedure for detecting justifiable asperity summits from surface topography data and proposed a quantitative assessment of their spatial distribution. The smoothing and differentiation technique was applied to seeking for one local summit within an assessment area. The assessment area was introduced by the use of autocorrelation function on the related surface. As an auxiliary assessment of surface topography, the smoothed slope in the three-dimensions was also defined on the assessment area. Little variation in the slope parameters was found in the case of more than five sampling points for one side of the assessment area. The spatial distribution of the detected summits was characterized both in the vertical and lateral directions. The summit height distribution was assessed by the bias and standard deviation. For the latter direction, a dispersion index composed of the areal density of summits and the mean nearest-distance among summits was presented.

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The parts feeder of a bowl type which has been widely utilized in the automatic assembly line of the factory is constituted by the bowl, the spring and driving mechanism. The usual feeder has the inclined leaf springs to give the bowl the vibration with the components of vertical and rotary directions. By using such a vibration. the parts can be conveyed along the passage provided on the bowl. In the new feeder stated in this paper, the FRR (fiber reinforced rubber) cylinder is used instead of the leaf springs. Because of the anisotropic elasticity of the FRB material, the bowl of the feeder vibrates in the same manner as that of the feeder with the leaf springs, and also has the parts feeding ability. Here, the experimental results obtaind in the new feeder of the howl type are described and the vibration of the feeder by the electromagnetic drive and conveying velocity are analyzed theoretically.

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The paper describes a new variable-attractive-force impact damper and its application to eliminate chatter vibrations in cutting process. The effectiveness of plain impact damper is somewhat limited due to non-linearity such as the damping effect depend upon vibration amplitude. For improving the effectiveness, the variable-attractive-force impact damper system is proposed and developed. The system is mainly composed of an electromagnet with a Hall-effect sensor, a vibration sensor, and feedback control amplifiers. This system is applied to eliminate chatter vibrations in face milling process for very-weak-workpieces. The cutting tests revealed that the system is very effective and versatile for stopping chatter vibrations.

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This paper describes a system that inspects the inner wall of plated through-holes in high-density printed circuit boards. These through-holes sometimes contain “void defects”, in which part of the copper plating is missing. These voids are detected by means of fluorescence emissions from the base material of the P.C.Bs. The paper describes an optical system for illuminating the inside of a through-holes, and for detecting fluorescence emitted from the void. This system can detect voids as small as φ 150 μm on the wall of a through-hole of diameter of 0.24 mm at depth of up to 3.5 mm.

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According to JIS (Japan Industrial Standard), definition of positioning accuracy about the robots is clearly described but the measurement method of the accuracy is not described concretely. In this study a measurement method of positioning accuracy using the reference plate with grid patterns and the image processing probe with CCD camera is proposed. This measurement procedure consists of two steps. In the first step, the positions of grids on the reference plate are measured by the probe mounted on the 3-D coordinate measuring machine. In the second step, the robot is commanded to move at each position of grids on the plate placed in the robot's working area and then positioning accuracy about the robot is measured by calculating the difference between commanded position and performed position. The detective accuracy for certain grid is within 0.6 μm in standard deviation and that for 9 grid patterns in the 400×360 mm area is within 3 μm. And this method is actually applied to a SCARA robot.

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This paper describes an in-pipe microrobot to which the motion of an earthworm is applied. A new locomotive unit for the robot is proposed, and the unit was made of two plates connected with an Flexible Micro Actuator (FMA) and four linkages as the legs. The static and dynamic characteristics of FMA were experimentally investigated, and the nonlinear stiffness and the viscous damping were identified. From the driving experiments with a prototype of the robot, which was composed of the three locomotive units, the maximum speed of 2.2mm/s and the maximum traction load of 0.22N were obtained in a pipe 21mm in diameter. The speed of the robot was also theoretically analyzed by taking account of the delay of shrinking of FMA, which was estimated with the identified characteristics, the theoretical speed agreed well with the measured speed.

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A piezoelectric cycloid motor, which was proposed in a previous paper, is composed of an internal and external gear pair and four drive units containing piezoelectric actuators. The motor has hence some merits which arise from gear drive: no slip motion, long life, and precise motion. It has moreover an excellent characteristics that it rotates steadily and keeps its rotational speed up to its maximum output torque at any rotational speed. The efficiency increases as the rotational speed and the load increase. The motor, however, is subject to a drawback in that it is very difficult to miniaturize because the motor requires four magnifying lever mechanisms to increase the very small displacement, l0μm, of a piezoelectric actuator. In this paper, an electromagnetic cycloid motor is proposed, which is directly driven by four electromagnetic linear actuators instead of the four drive units. The motor rotates based on the same principle as the piezoelectric cycloid motor, but is not subject to the drawback. The output characteristics are experimentally and theoretically investigated.

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Three-dimensional internal structure microscope (3D-ism) using a microslicer has been developed.The 3D-ism consists of the microslicer, optical microscope, CCD camera, video recorder, PC for controlling the machine, and image processing workstation. The 3D-ism is the system that mechanically cross-sections a sample by microslicer, and observes the surface of the sample by reflecting optical microscope one by one, even in conventional way the sliced thin samples are observed by transmission optical microscope. The system reconstructs a 3D image from the obtained 2D image data. This paper describes the motivation for 3D-ism in such various fields as education of biology and cell inspections, and describes the construction of the system. This paper also presents ring-lighting to observe the colors of the sample, and an image-processing method to observe the top section data. Finally some of example 3D images of the samples are presented, such as liver and kidney of mouse, a dog tick, and a bud of broccoli.

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A laser beam delivery control system has been designed to align a laser beam axis and monitor its beam properties such as beam position, beam diameter, power, peak power and 3-D profile. A laser machining system for long term operation will make this system necessary because those beam qualities will be changed. The developed system is composed of two beam sensors, two angle control bending mirrors with actuators, and a host controller. A rotating wire method was applied for this sensor. In this system, the accuracy of the beam diameter was ±0.5 mm compared with the measurement from a burn pattern of acrylic resin. A far-field laser beam position of 17 m away from an oscillator could have been measured and controlled automatically within an accuracy of ±1 mm under on-line conditions. Thus this developed system is very promising for evaluating beam qualities.

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Recently, the microactuators that utilized electrostatic motor, piezoelectric device and shape memory alloy were developed. However, these microactuators are limited to plane constitution when the constitution is a micro machine. Accordingly, it is difficult to power transmission to arbitrary direction by using this system. In this paper, the pressure transmission system that used magnetic fluid is proposed. This system has the possibility of power transmission in arbitrary direction. Namely, this system enables spatial power transmission by opening a hole and linking it. Magnetic fluid driven by the external magnetic field was used as the new hydraulic microactuator. When the external magnetic field is applied to a magnetic fluid, magnetic pressure occurs. The generated magnetic pressure was studied. Conclusions are summarized as follows : (1) The magnetic pressure becomes higher, as the diameter of capillary tube becomes smaller. (2) The diameter of the capillary tube influences to the relation between magnetic pressure and the duty of the pulse. (3) AC is preferable for electric power, since the obtained magnetic pressures were 50%-80% of DC. At present, if a size of solenoid is not millimeter order, practical things is difficult. However, can drive fluid directly is a big advantage. Therefore, it is conceivable that the research of a micro solenoid is important for this magnetic fluid system.

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Although three dimensional photofabrication is one of the new technologies that can make three dimensional parts using a simple process, improving, parts accuracy is one of the demands for industrial use. The knowledge of the mechanism of a solidified resin's unit shape will lead to the improvement of parts accuracy. This paper shows the measured and the analytical results of the solidified unit shapes where the laser-focal position is changed to the uncured resin surface. The results showed that solidified shape had a constricted profile at the mid point of slopes rather than a parabola profile where uncured resin surface was offset from the focal position. The analysis of the results clarified that these unit shapes should he estimated from the energy distribution irradiated on the uncured resin surface rather than the Gaussian energy distribution based on conventional assumption.

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Grinding center has been developed to built up an automatic grinding system. The grinding center can grind various kinds of surfaces simply by changing the grinding wheel accordingly. However there are some problems when using a cup wheel for face grinding. Specifically there is the problem of grinding seizure, which must be rectified immediately as this sometimes causes wheel fracture and grinding burn. This paper discusses the newly developed grinding wheel base, and the results of truing the bottom surface of the cup wheel at a small angle for use in face grinding. The function of this base is to draw coolant in and supply to the grinding point in order to prevent the seizure. It becomes clear that this newly developed wheel base and the slant truing on cup wheel surface are very effective for face grinding. As a result prospects are bright for the fabrication of automatic grinding systems by the grinding center.

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In this report in order to make clear the form generation mechanism in the internal plunge grinding process, the thermal deformations of wheel and workpiece are measured with both workpiece width and grinding time. Main conclusions obtained are as follows: (1) In the internal plunge grinding, by contrast to the surface or external grinding, the workpiece surface expands with the thermal deformation in the opposite direction of wheel surface. (2) The ground workpiece profile becomes an extremely concave profile, because the wheel surface expands just like a barrel shape due to the thermal deformation of wheel. (3) In contraction process of the thermal deformation of workpiece the concavity decreases but after grinding the concavity is left as an error of surface profile.

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6-Axis control machining with a non-rotational cutting tool can show the potential of new machining technology. The study deals with the development of a software system for asymmetrical grooving on a sculptured surface by use of a non-rotational cutting tool. The shape of the tool is the same as the cross section of the groove. Asymmetrical grooving, which is impossible to machine with 3-to 5-axis control, is one of the characteristic features of 6-axis control machining. The system cosists of two stages: the first is to define a groove path and a groove shape with an asymmetrical cross section, the second is to paste the groove path together on the workpiece surface and to generate CL data corresponding to the groove shape, taking account of overcutting and collisions. Generated CL data are then converted to NC data for a 6-axis control machining center by the postprocessor. This software system shows the validity of 6-axis asymmetrical grooving.

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In laser surface modification with a molten state, cracks are generated on the laser irradiated surfaces under unsuitable conditions. This phenomenon is one of the main problems regarding industrial use. In this study, it is considered that the generation of cracks will be caused by a tensile stress based on the phase change of material. Thus, an analysis of thermal stress including the phase changed process is suggested. The thermal stress distribution is calculated using FEM with consideration of the complicated boundary conditions due to the phase change. And, the laser beam was practically irradiated on the surface of cemented carbide. The forms of generated cracks were examined, and the following results were obtained. Tensile stress above 1200 MPa arises in the solidified region of material, whose value exceeds the tensile strength of material used. The behaviour of generated cracks could be obviously explained with consideration of both the change with time and spatial distribution of the thermal stress.

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The indenter tip of a scratch tester used for measuring adhesion of hard films is conventionally made of singlecrystal natural diamond. However, it has the problem of a short lifetime due to its tendency to cleave, leading to our attempt to replace it with CVD polycrystalline diamond. This paper deals with the results of an evaluation test in which two kinds of indenter tips were subjected to repeated scratch operations using an actual tester; one tip was made of single-crystal natural diamond and the other was made of 0.7mm-thick CVD wlycrystalline diamond. The following results were obtained; (1) The tip made of polycrystalline CVD diamond has a lifetime two or three times longer than that made of single-crystal natural diamond. (2) Single-crystal diamond indenter shows strong dependency on the relationship between crystal direction, scratch direction and loading direction as to the measured critical load value even when used for the same film sample, thus leading to a necessity to control the crystal on loading directions in order to obtain a well defined critical load value. (3) Polycrystalline diamond is free from a necessity to control crystal orientation in manufacturing good quality scratch indenters in terms of the said scatter.

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This paper deals with a new truing technique for grinding wheels in which cutting edges on the grinding wheel are machined and lapped in a newly designed ultra-precision grinding machine. The newly developed grinding machine has a measuring device for cutting edge height and rotating spindles for a grinding wheel and a workpiece. Each spindle stiffness is 1 kN/μm. After applying the newly developed truing process to a #1500 diamond grinding wheel on the grinding machine, the number of accumulative cutting edges below 0.5 μm depth from the outmost wheel surface were increased by more than 32 times compared to conventional truing process. In-feed grinding achieved a surface roughness of 7 nmR_max in ductile mode on optical glass BK 7 by a #1500 diamond grinding wheel with cutting edges of unified height.

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In grinding ceramic materials, the strength of ceramics is affected by the workpiece surface roughness and the cracks on subsurface formed during grinding operation. The truing speed-ratio S (the ratio of truer peripheral speed to wheel peripheral speed) can be varied to modify the wheel topography, with resulting changes in the grinding forces and the workpiece surface roughness. In this study, influence of the truing speed-ratio S and bond marterials on the strength of ground ceramics was investigated experimentally and the relation between the wheel topography and the strength of ground ceramics was also discussed. The experimental results indicate that there exists suitable truing speed-ratio to obtain the highest strength for grinding ceramics. The strength of ground ceramics declines when the diamond wheel is extremely sharp as well as extremely dull. It is suggestive that selecting truing speed-ratio is very important for grinding ceramics in order to guarantee the strength of ceramics. It is also pointed out that the strength is affected by elastic modulus of bond materials remarkably. The strength deterioration will be lower when ceramics was ground by wheels with low elastic modulus such as resin-bonded wheels than that by wheels with high elastic modulus.

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