In this paper, a dynamic analysis on the balancing of the fluctuating input torque in a planar multi-link conveying machine is carried out, as a practical example of an automatic conveying machine which generates an L-path. Namely a planar 12-link conveying machine is proposed, which is made by joining a slider-crank mechanism to the input link of the 9-link mechanism, for the purpose of neglecting the influences of the inertia force in the links. Moreover, optimum distributed masses and moments of inertia of the plural oscillating links are determined so as to reduce the fluctuation of the torque affecting input link. Based on the above analytical results, the dynamic characteristics of the machine are investigated theoretically and experimentally. As a result, it has been obvious that the maximum magnitudes of the torque affecting the input link reduce up to approximately one third the level of that which was measured at a state of unbalance. At the same time, the positioning accuracy of the machine hand at the edge points of the path can be greatly improved.

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On the direct measurement of roundness of cylinder, the reading of the indicator generally includes the rotating error of the measuring system. However the measurement system of roundness using a vee block and indicator has no rotating errors in the readings. The most serious disadvantage of this arrangement lies in the difficulty of establishing the actual shape of the circular parts by the readings of the dial indicator, which will depend on the used angle of the vee block and on the number of lobes present on the circular part. But this disadvantage will be now improved by applying this arrangement procedure since the calculated or analyzed values of the readings will be able to establish the actual shape of the circular parts if the values will be selected suitably. The selected angles of the vee block are used 60°, 90°, .120°, .135° and 180° in this experiment. By this procedure the standard shape will be able not only to measure but also to know the rotating accuracy of the measuring system.

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A newly developed Cycloid Ball Reducer is introduced and analyzed. The fundamental element of the reducer consists of three components ; two surface-grooved discs and a train of balls. One of the discs has an epicycloidal-wave groove on one side of its surface, while the other disc has a hypocycloidal-wave groove. The two grooves face each other, and between them balls are arranged in a uniform angular pitch. The balls transmit torque between the two discs. A proper amount of thrust force is applied axially to eliminate backlash. This Cycloid Ball Reducer is suitable for application to servo mechanisms and robots. It is compact and easy to build in a unit, and has a large torque capacity. In this report, the principle of the reducer is analyzed using polar complex vectors. It is proved that the reducer has linear characteristics in principle. The reduction ratio can be chosen a wide range.

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This paper describes a new method of precise positioning using piezoelectric elements. The method utilizes the friction force between the object to be moved and the base plane, and the reaction of the inertial force caused by a rapid deformation of a piezoelectric element. The configuration of this positioning mechanism is simple : an element for inertial mass is connected to the object to be moved by a piezoelectric element. Through controlling the rapid deformation of the piezoelectric element, we can control the inertial force, which causes a controlled step-like movement of some nanometers up to some ten-micrometers. Repeating this stepping action, it is possible to move the positioner with a velocity of more than one millimeter per second. Applying a sensor feedback to the mechanism, almost the same resolution and accuracy as the sensor can be achieved in position control. This method of positioning also realizes a remarkably simple 3-axial precise positioning table.

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This paper introduces a design procedure of precise linear feed mechanism by an application of friction drive. The principle of this mechanism is that the rotational motion of drive shaft is converted into the linear motion of driven bar by the traction force at their contact point. This procedure consists of two parts of accuracy and strength analysis. Namely, the effect of drive shaft geometry and its motion on the positioning accuracy is analyzed first. Secondly the critical contact force, which is constrained by the yielding of member's material, is analyzed by the help of Hertzian contact theory. These analyses are summarized in the form of design parameter. Two prototypes with a line contact or a point contact, where the members were supported either by anti-friction rollers or aerostatic bearings, were made and tested, showing the results of up to 0.025 μm step feed.

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Recently, in high technology industry, gas bearings have been used in high speed spindles owing to low friction, and in ultra precision cutting machines by the use of clean air. The pocketed orifices are adapted to their requirements, and it is known that the bearing performances are defined as stiffness and damping, and that the shaft movement is predicted by damping factor (ξ) of the bearing system. But it is not clear how the shaft movement is affected by their values. In this paper, journal center locus is measured when an impact force acts on the shaft, and theoretical calculations and experimental results are compared. Following conclusions are obtained : (1) A shaft movement behavior is affected by supply pressure, but when the bearing clearance is set to the optimum value (10 μm), damping factor gets to greater than 0.4 at any supply pressure. (2) When a disturbance force acts on the shaft at every rotational cycle time interval, if damping factor gets to greater than 0.2-0.3, the shaft comes to the steady state condition within 1-2 periods of rotational cycle time.

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Mechanism and control design of magnetically suspended multiple degree-of-freedom (D.O.F.) positioners are described. One of the most important problems of the mechanism is optimal location of electromagnets and sensors. The general condition of mechanical decoupling is derived using a general electromagnet location matrix determined by the geometric positions and attitudes of the electromagnets. An electromagnet locating method robust to magnetic parameter change is proposed using singular value decomposition representation. A controller that has an arbitrary bandwidth and damping coefficient with respect to each. D.O.F. and minimal energy loss through the electromagnets is proposed using a generalized inverse of the electromagnet location matrix. As an example, a 5 D.O.F. model with 6 electromagnets was designed and experimental results supporting the design were obtained.

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The present research aims at developing a method for measuring particle sizes of order of nanometer (nm) on the raw Si wafer using a light-scattering method with Ar+ laser. According to the analysis for Mie and Rayleigh scattering theories, the measuring system is developed to detect the particle of nm order sizes with the ellipsoidal reflector collecting extremely weak light, the detected processing system, and the several optical instruments. Furthermore, a melting problem of the particle irradiated by the laser is clarified by analyzing the heat conduction to a particle theoretically. Consequently, it was verified theoretically that the measuring method developed in this study is applicable for detecting the nm order sizes nondestructively.

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In order to obtain the single crystal diamond tools which have clear crystallographical orientation of the tool faces, the lapping method with identifying technique by the X-ray diffraction is studied. The lapping temperature is measured as well as the lapping forces and the total lapping depth to consider a lapping mechanism of the diamond tool. The addition of oscillation to the lapping operation lowers all the tangential lapping force, the lapping temperature and the total lapping depth, which have more effect on so called card to lap <110> direction on {110} plane than on easy to lap <100> direction on {110} plane. It is also found that the lapping temperature increases with the normal force to the lap, but the lapping force ratio (tangential force/normal force) decreases, and that the lapping surface roughness of diamond by the oscillatory lapping is superior to one by the non-oscillatory lapping.

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This paper describes a behaviour of the orthogonal cutting strain in the aluminum workpiece. The cutting strain is measured with a fixed quantity by a photoelastic coating method. The components of an instantaneous cutting strain and a residual one are separated from the observation. The results obtained through this study are as follows : (1) The comportment of the cutting strain in the ductile material is disclosed using the photoelastic coating method. (2) The behaviour of the cutting strain in the strain hardening material is similar to that of the elastic material.

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This paper deals with a high speed drilling of alumina green sheet with a fine focused electron beam. Some experiments to drill many holes in a 16 × 16 mm² area by means of single pulse beam scanning with beam deflection were performed and the following results were obtained. (1) The diameter increase is observed during machining when the time interval of beam pulses is short. This diameter increase is due to upward focal movement of an electron beam focused on the workpiece surface by the influence of the gas which is generated by the thermal degradation of organic binding material in the green sheet. (2) The increment in diameter decreases logarithmicly according to the increase in time interval of beam pulses and also decreases somewhat according to the increase in distance between holes. (3) The diameter increase can be compensated by a dynamic focus control which cancels the actual focal movement in a machining.

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Cast iron bonded diamond (FC-D) grinding wheel is now used for ceramics grinding due to its high performance. The grinding mechanism is investigated experimentally by the measurement of grinding force in rather slow wheel speed and the observation of wear behaviours of abrasives. Main results are : (1) The grinding mechanism of the cast iron bonded grinding wheels resembles that of the metal bonded diamond wheel but the wheel deformation is small and drops of abrasives are not so often in FC-D wheel even under the heavy duty grinding, because the wheel stiffness and holding strength of abrasive are both very high. (2) It is possible to use the FC-D grinding wheel under the condition of flat topped abrasives. In this case, though the grinding force becomes higher, the roughness of ground surface is improved and the grinding ratio is high. (3) When the protrusion amount of abrasives from bonding surface is not enough, the sparking phenomena occurs by the direct contact between bond material and ceramics in heavy grinding and this leads to dressing effect.

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In this paper the fundamental investigations are performed to extend the probability of application of Caustics experimental method to various stress analytical problems in new studying fields. Under simplified two dimensional condition, the object of study is a half plane with discontinuously distributing oblique load divided 2 or 3 parts over loading region. Specimens are made of acrylate resin plate of about 3 mm thickness. The Caustics patterns formed by reflected lights from the both surfaces of plate are observed and those characteristics with loading conditions are investigated in detail. On the other hand the computational patterns based on optical theory are plotted. These two patterns are coincided accurately enough.

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In the magnetic abrasive finishing process utilizing a magnetic field, a new surface finishing apparatus is developed in which the N and S magnetic poles are vibrated and a workpiece is rotated only, in stead of the conventional surface finishing apparatus in which the magnetic poles are steady state and a workpiece is rotated and vibrated simultaneously. This paper describes the newly developed unit system finishing apparatus and its finishing performance examined experimentally. From the experimental results, it is found that the vibration effects of magnetic poles on the finishing characteristics are large in cylindrical and internal finishing respectively.

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Based on the fact that friction test between a grinding wheel face and a P. T. F. E. piece is a very simple and practical method for evaluation of the grinding wheel sharpness, this paper presents an application of this method to the in-process sharpness measurement of a rotating grinding wheel under wet condition. The coefficient of friction measured by this method tells us the wheel sharpness and is found to have intimate relation to the tangential and normal grinding forces. Measuring procedure of this method can be automated by a micro processor and is expected to be a useful setup for unmanned grinding systems.

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In sheet metal part manufacturing, bending is most commonly used in order to obtain rigidity and to obtain a part of desired shape to perform a certain function. The importance of process planning automation is well understood, and recently some experimental CAPP systems for bending operations have been constructed. However, current CAPP systems lack the ability of simulating the sheet metal bending modification, so many kinds of process planning constraints are difficult to utilize. To solve this problem, a bending operation simulator is developed and incorporated in our new process planning system AMPS. This simulator manipulates the modification of the sheet metal part as the transformation of thin plate solid models which represent the geometrical shape of the sheet metal part. By using the simulation result effectively for evaluating the constraints, process planning of complicated sheet metal part is computerized.

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This paper considers a possibility of decision whether the robot hand is having a correct work or not by using the analysis of the mechanical vibration of robot that is doing an operation. The dynamics of robot is changed by the various works that the robot hand has or the incorrect movements of robot, and this change of robot dynamics can be analyzed by the residual vibration of robot. Here, this study showed that the state of operation of robot could be recognized on-line operation of robot by using a vibration analysis of robot that is the AR (Autoregressive) Model method.

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This paper describes the global-conception of the knowledge-based consulting system for the finite element structural analysis and partially implemented a consulting system called MESHELP for the finite element mesh generation. The know-how and expert's knowledge about mesh generation in the finite element structural analysis are defined clearly as mesh generation rules. This mesh generation rules are stored in knowledge data base. By using these rules, any beginner in structural analysis is able to judge the right or wrong of mesh, and moreover, to master mesh generation techniques for himself. In MESHELP system, user only answer a series of question putted from MESHELP system. Then, MESHELP system inferentially decide the right or wrong of mesh by using mesh generation rules in knowledge data base. In order to help user answer the question, a lot of figures for additional explanation are stored in knowledge data base.

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