The jumping in synchronous belt drives occurs on the driven pulley when the number of the driving and the driven pulley teeth is the same and the wrapping angle of the belt on both pulleys is π radian. However, when the pulley rotates at quite a low speed (2 rpm), overload is rapidly applied on the driven pulley which causes jumping on the driving pulley. Jumping over of the synchronous belt drives is caused by the belt teeth climbing on the pulley teeth in combination with elastic deformation of the belt and the supporting shafts and bearings. Belt teeth climbing starts from the slack side belt in both of the driving pulley jumping and the driven pulley jumping. The belt tooth climbing progresses from the slack side to the tight side belt. Theses facts can be conformed by the simulation of dynamic finite element analysis. In this study, "ABAQUS/Explicit" and "ABAQUS/Standard" were used for the simulation.

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In some printers and copy machines, one of the methods for reducing belt skew is using pulley with smaller diameter. But a smaller diameter causes the early crack on the surface of the belt. In this research, FE analyses are carried out for examining the influence of the belt tension on the belt skew. The results show that the tension distribution influences the skew only within a short period when the belt start moving. And it seems that the skew is only dominated by the geometrical parameters of the belt and pulley in the case without torque load.

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Euler's formula is well known as the fundamental of theory of flat belt transmission, which gives the tension distribution of a single belt winding on a pulley. In a sandwich-belt conveyor system, however, there is at least one pulley on which two belts wind, and the conventional Euler's formula can not be applied in so called twofold winding. In this paper, a theoretical analysis of twofold winding of belts is provided and verified by using FEM through examples.

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3-D contact area of hypoid gear simulation result must be transformed into a plane to compare it with experimental tooth contact pattern. However, tooth flank of generate face milled hypoid gear can not be transformed directly into a plane because of its complex tooth form. Conventional analysis employs projecting 3-D contact area into a plane, but it is not easy to compare its simulation result with experimental one. In this report, the method of transforming contact pattern is proposed, where 3-D contact area is projected into a circular cone approximate to tooth face.

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The gear sound was reduced by reducing the meshing transmission error to decrease the gear noise up to now. However, there is no research that considers even human aural characteristic yet. Therefore, we aim to investigate and propose the design method of the low noise gear, which considers even human aural characteristic. The proposed technique is a gear design according to controlling the frequency of the gear sound not heard on human aural. First of all, human aural characteristic was shown in a special acoustic environment in the car. In addition, the relation between the number of gear teeth and the sound pressure level of the gear sound was shown. Finally, it was clarified that this technique was effective to the design of an advantageous number of gear teeth on the aural characteristic.

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In order to develop an assisting device in standing up for aged persons, standing up motions were analyzed for both young and aged persons. A prototype device was attached onto the lower legs of a subject to estimate the required torque to assist the standing up motion. The device consists of an aluminum frame, fastening belts, and a geared motor which applies the auxiliary moment to the knee joint. The test results show that the maximum torque of the actuator decreases when the trunk declines forward. It is also effective to give small angle between upper and lower legs at the knee before the standing up motion to reduce the maximum torque of the actuator.

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This paper presents a study on reversible rotating spiral-grooved thrust bearings (SGB) named 'ribbon type bearing'. It is lubricated by a forced injection of liquid in order to reduce a bearing starting torque. Thus, compared with a conventional hydrodynamic SGB, the ribbon type bearing achieves higher load capacity and lower bearing loss by the assistance of hydrostatic action. The ribbon type bearing consists of radius grooves and inflow grooves. Effect of the groove depth is experimentally investigated in thin paper. By the experiment, it is shown that the groove depth of about 100μm is recommendable from the view point of low bearing temperature raising and high load capacity.

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Using a rotating friction tester of ball-on-disk type, influence of surface temperature on the boundary lubrication characteristics of mineral lubricating oils was examined. The tester consists of a ball and a disk installed an electric heater to control its surface temperature. The sliding speed was slowed down to minimize the frictional heating as well as hydrodynamic pressure generation between the ball and disk. In this paper, the critical temperature yielding the growth of friction coefficient was examined for paraffinic-naphthenic base oils with and without fatty acid oiliness agents. The results can be summarized as follows; 1) the critical temperature of paraffinic-naphthenic base oils exhibits viscosity-dependence; 2) so-called chain-matching between base oil and oiliness agent has some effect on the critical temperature besides molecular weight of the agent.

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Recently, the spread of the micro gas turbine is hoped for an effective use of energy. Air-lubricated foil bearings that can be adaptable to a high temperature environment and high-speed rotation are applied to such a micro gas turbine. To make use of the foil bearings to the micro gas turbine expected as a distributed energy source and a movable power supply, there is a problem of scarceness of the damping performance. In this study, the authors propose a new bearing structure in which the glass wool was given to improve the damping characteristics and examined its performance experimentally.

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This paper describes an experimental study on the effect of texturing on tribological characteristics of metal surfaces in lubricated sliding contacts. The experiments were performed on a slider-disc test machine. Slider specimens made of brass have micro grooves parallel to the sliding direction. They are pressed on a cast iron rotating disc by stepwise loading. The width ratio of groove to land, and the depth of groove were fixed at given values, and the pitch and the widths of grooves were varied. The result shows that, if the grooves exist, the severe wear happens but scuffing does not happen at once after specimens contact the disc.

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Heavily loaded sliding pairs in mechanical systems are always exposed to risks of seizure. To minimize such risks, certain extreme pressure additives and/or solid lubricants are added to the lubricating oil. As an alternative or an additional means, the authors propose to provide one of mating surfaces with numerous micro-holes without any macroscopic changes in the hydrodynamic oil film. When such a macroscopic oil film breaks down, frictional heating makes the absorbed boundary films to be easily scraped off. Frictional heating, however, extrudes the oil contained in the micro-holes to retrieve the scraped boundary films. In the present study, using a test machine which models a circular thrust bearing for a screw press spindle, seizure prevention ability of such micro-holes on a bearing surface is examined experimentally.

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To improve surface fatigue strength is very important in machine elements in rolling-sliding contact, such as gears. Although the surface roughness is considered to cause detrimental effects, the directivity of the texture has the effects of promoting an oil film formation and of improving the pitting durability. Also, the directivity of the periodic structures, which were generated on the surface by linear polarized femtosecond laser, influences the lubricating characteristics in sliding contact. In this report, the authors examined the effects of such periodic structures on pitting durability in rolling-sliding contact. As a result, we found a great pit and heavy scar on the follower of ground-ground roller pair, by contrast a few pits of much smaller size were merely found on follower of ground-periodically structured roller pair. The results demonstrate the great effect of such periodic structures on the pitting durability in rolling sliding contact.

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Air-lubricated foil bearings are applicable to a bearing system for a micro gas turbin in a distributed energy source. To develop such bearings of simple structure which can adjust to severe conditions of high temperature and high-speed rotation, in this study, a tension type foil bearings of new structure is proposed, and its performance is examined experimentally.

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It is a proposition for manufacturing to shorten the time of the product development, and to send off the product suitable for consumer needs promptly. Then, processing information at the time of cutting RP is acquired, and the development by the delivery of processing information to the real processing is aimed at. The current of the spindle motor was acquired as processing information, and the analysis was tried.

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In cell production system, corresponding to the variety and variate production, the small and process consolidated machine tool is needed. In this study, a desktop size multifunctional machine tool is developed. And first, basic moving performance of the development machine was measured. In addition, power consumption and thermal deformation of this mini machine tool were measured.

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It is important how to use the engineer's knowledge and experience for the manufacturing system. And "Accumulation of the improvement" based on them is indispensable. The purpose of this research is to discover the new ideas of a suitable manufacturing process for the manufacturing system of the engineer by introducing the data mining technology into the site, and to achieve the environment that can support "Accumulation of the improvement". We paid attention to tool selection that first became important in manufacturing it this time.

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Today, the correspondence system is requested to variety and amount in the manufacturing system. On the other hand a traffic engineering is considered as the representative concerning the flow in a different region of research. As one example of mimetic solution then, especially, the delivery problem of paying attention to the movement characteristic of the taxi was considered of the system corresponding to variety and amount and catching, and the adjustment to the manufacturing system in the paper.

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In this study, laser soldering of lead-free solder, which has promoted for environmental protection, was investigated. Laser soldering has been commonly performed by scanning of a laser beam on solder areas. However, it has problems with tomb stoning and jointed chip components with a lean. Here we propose the multi-spot simultaneous laser soldering by use of Holographic Optical Element (HOE). For that purpose, the HOE was designed and fabricated. And samples which were soldered two-spot simultaneously were compared with samples which were soldered in the scanning method. Additionally, the solder joints of Sn-Ag-Cu solder were equal to eutectic Sn-Pb solder. But the solder joints of Sn-Zn-Bi solder were low in comparison with the one of Sn-Pb and Sn-Ag-Cu because of poor wettability. Hence, we investigated about the improvement of wettability by preheating. The mechanical reliability of soldering was evaluated by joint strength test.

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In a bag-packing problem, several items having different weights are picked out so that the sum weight should be closest to the given desired weight. In some cases, a solution that satisfies all the constraints cannot be obtained. When the solution cannot be obtained, such function is introduced that input materials are added to one scale hopper in order to renew a problem. For the renewed problem, a searching algorithm is executed again. But the problem is how many input materials are added so that the total number of eliminated items can be decreased. In this paper, the limit weight of input materials in addition is examined.

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This paper describes a insertion model by using a fixture with the passive elasticity function on the side to be inserted. Previously, the skilful function as RCC for complex assembly has been prepared for on the insertion side like a hand manipulator, not on the side to be inserted like a fixture. Therefore the feature of a fixture with the passive elasticity function in the insertion work is elucidated. The insertion work model with this fixture is composed of vertical (x-z) plane. And this feature is investigated by the quasi-static analysis, which was proposed by Whitney. As the result of the analysis, behavior of insertion process and power to act on elastic center, transition of contact condition including jamming has been clarified.

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This paper presents a methodology to calibrate kinematic parameters in a Hexapod-type parallel kinematic machine tool. In general, the calibration error of kinematic parameters and the deformation of struts due to the gravity are two major causes of motion errors of a parallel kinematic machine tool. In other words, in order to accurately calibrate kinematic parameters from measured contouring error profiles, it is important to separate the effect of the gravity from them. We propose a calibration method under the cancellation of gravity-induced errors. Experimental comparison shows circularity errors measured in conditions where gravity effect is large are significantly improved by using the proposed calibration method.

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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, and also with the unscheduled disruptions. They are so called autonomous manufacturing systems like random manufacturing systems, biological manufacturing systems, and holonic manufacturing systems. The purpose of the present research is to develop an integrated process planning and scheduling system, which is applicable to the holonic manufacturing systems. A systematic method is proposed to determine both the machining sequence of the individual products and the production schedules for the multi-products i.e. schedule of the individual machining equipment. A stepwise method of GA (Genetic Algorithm) and load balancing is proposed first for the loading planning of entire products, then a method based on GA and DP (Dynamic Programming) is proposed for the process planning of each product, and finally a method of GA and Dispatching Rule is developed for the production scheduling of the entire products.

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A reactive scheduling method based on GA (Genetic Algorithm) was proposed in the previous research. The method can improve the delayed production schedules by unscheduled changes, without interrupting the progress of the manufacturing process. This research improves the reactive scheduling method for multi-objective problems by using multi-objective GA.

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Since consumer's needs dynamically change, manufacturing systems are required for changing manufacturing performance, such as manufacturing volume and cycle time, continuously. A new flexible manufacturing system called cellular manufacturing systems are proposed in order to satisfy this requirement. Cellular manufacturing systems need a suitable control method to change the manufacturing performance in case of unforeseen changes, such as delays of manufacturing processes. This research proposes a dynamic reallocation method of workers in cellular manufacturing systems. This method dynamically provides an allocation of workers in order to minimize the tardiness of jobs. A prototype of reallocation support system was developed to evaluate the effectiveness of the proposed method.

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An incidence of motion sickness caused by cars and trains arises from complicated interaction related to human body, characteristics of vehicle, irregularity of road and speed of vehicle. This paper presents an evaluation method of motion sickness incidence taking account of running condition of vehicle. A computer program was developed for analysis of Motion Sickness Dose Value by using frequency weighted curve of ISO2631-1. The effect of encounter period to road pattern on motion sickness incident was discussed. Some analytical examples are shown for acceleration records measured at the loops in a mountain road.

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Phasic stress may be estimated by using the Respiratory Sinus Arrhythmia (RSA), which is variation of heart rate mediated by parasympathetic nerve. However, the RSA amplitude is also accompanied with respiration, such as tidal volume and breathing frequency. This paper addresses expiratory-time-based normalization of RSA amplitude, and estimation method of the trend of normalized RSA amplitude.

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Four legs animals automatically choose the most efficient gait pattern according to the walking speed. This paper describes the mechanism of this automatic selection of gait, from the view point of the natural vibration mode. Then rigid body link model was made and analyzed, by simply modeling quadruped walk. The results have shown that the mode shapes of this model are the same gait as animals walk.

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This paper addressed the motion of passive dynamic walking mechanism on a flat floor. We made a simple linkage machine which omits ankle joints, knee joints and an upper body. In our previous works, we have proposed the consistency of natural frequencies in swing and rocking motion is important for energy-effective passive walking. In this paper, we discussed on the unexpected waist motion. Then, we showed the sub-system which moves like an upper body is effective for avoiding the unexpected waist motion. Sub-system on the waist makes the motion of swing and waist in-phase. Therefore, the steps of test machine may be increased.

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The analysis of coupled vibration of the arm, the tennis racket and the ball is important to understand the performance of the racket and to prevent of sports diseases when people play tennis. The arm is modeled as musculo-skeletal model includiing activity level, and the ball and the racket are modeled by masses, rigid links, respectively, which are connected by springs and dampers. By coupling the dynamics of the ball, the racket, and the arm, the coupled equation of motion is derived. The feedback error learning system is introduced to obtain the activity level of muscle. And we calculate the holding moment between hand and racket from feedback error learning system. Finally this proposed analysis method is compared with the former analysis and experimental results.

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The DLT method is often used to analyze the golf swing motion. This paper proposes the correction method of the measured error which is occurred in the image. As a human body is modeled by links, link length is constant and the measured angle between links become smooth curves in time series so to satisfy the condition the measurement point is corrected iteratively. To investigate the effect of this method, Monte Carlo simulation is used. Then it is known that this method is greatly improved the accuracy of measured point and the joint torque which is obtained by Newton Euler method.

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The object of this paper is to develop a dynamic design technique for the surf casting rod in order to maximize the flying distance of a sinker. The surf casting rod is modeled by link model and formulated by Nonlinear Multibody Dynamics method. The model is verified by the calculus of the resonance frequency and the modal forms of the fishing rod. Next, the model is checked under the throwing-in operation mode, by using Multibody Dynamics of the surf casting rod and the fishing line. Then, the model is used to examine how the flying distance of a sinker is influenced when the release location of fishing line links from reel or the characteristics of the surf casting rod are changed. Finally, one proves that such analysis is applicable as a dynamic design technique for the surf casting rod under the restriction of maximizing the flying distance of a sinker.

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The purpose of this research is to examine the technique to be able to transmit the skill to the nonskilled person from the feature of the swing of a skilled person. In this research, the upper limbs are imitated by the rigid link model, and the torque in each joint is calculated by using the Newton-Euler method. Next, the reproducibility of the swing and the motion of upper limbs when swinging are analyzed from coordinate data by using the singular value decomposition. The result shows the problem of the nonskilled person's swing is low reproducibility and the occurrence of needless torque. Then, the follows were found that the gap of the swing can be improved by obtaining a singular value axially each. A needless torque is suppressed by greatly moving the left arm. It was confirmed that the skill can be transmitted from the two techniques.

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This paper describes the technique for detecting an abnormal vibration of the rolling bearing of a practical rotating machinery. The rolling bearing is diagnosed from time domain vibration data measured by an accelerometer, and spectrum data obtained by the frequency analysis. Two diagnostic methods are proposed. One is the case that vibration data can be obtained from the normal rolling bearing. The other is the case that vibration data cannot be obtained from the normal rolling bearing. Then, the effectiveness of the diagnosis system was verified for the rolling bearing with defective ball, outer race and inner race.

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Recently, in order to increase the performances of rotating machinery, the radial clearance between the rotating shaft and casing became smaller and smaller. As a result, if the rotor contact with casing, severe self excited vibration frequently occurred in the rotating machinery systems, so called "Dry-Whip". Especially, self excited vibration with change of rotating speed (Contact type backward whirling) is able to occur under very small clearance condition such as practical rotating machinery. This work presents a theoretical and experimental study of such self excited vibration due to the rubbing which occurs on rotor and casing system with finite driving torque. As a result, it is shown that the rotor shows two deferent vibration behavior due to the natural frequency of casing. Those behavior shows deferent vibration phase of rotor and casing, zero or 180 degrees. And, it is shown that effect of physical condition of system for this phenomenon.

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The dynamic stability of gas-lubricated journal bearing with Herring-bone groove are investigated. The pressure distribution which is generated in compressible fluid at the gap in the bearing is caluculated. The equation of motion is derived using the fluid force and fluid moment acting on journal which is caluculated from the pressure distribution. On the basis of the derived equation, the numerical simulation of the dynamic behavior of the journal is performed. The vibrational mode and the stability of the behavior of the journal are investigated. Finally parameter studies are discussed.

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The field balancing is carried out after component-wise balancing in assembly rotor balancing process. However, in case there exist aged deterioration and running environment change, the field balancing is not enough. In this paper, a balancing method with component phase optimization based on influence coefficients method is studied. First, we show the robustness property on the rotor balancing. Then, the component phase optimization method and influence coefficient evaluation method is studied. The developed GUI based software for phase optimization for a specific assembly rotor is also introduced.

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It is important to assemble the turbine disks for minimum runout for realizing small vibration of the turbine. However the conventional disks phase assembly method to minimize runout depends on the worker's experience. So we paid attention to slight geometrical face error which exists in curvic couplings of the disks, and by modeling the turbine into the oblique swivel mechanism we enabled to presume runout of assembled rotor for any phase combination. And we established the calculation method of optimum runout considering dynamic balance.

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In this study, we develop a moving device with autonomy for handicapped persons so that they may use their own chair being accustomed to sit and can move without aid of helper in a Japanese-style room. The moving device can be controlled easily with a joystick and can mount an arbitrary seating system. Moreover, it has a function of the automatic operation for persons who don't have enough motor function to move and pass a narrow space such as doors.

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A self-propelled type of wheelchair with hand-rims has both advantages and disadvantages of operators. The former is to offer the convenience of mobility and the later is operator's fatigue. As a solution of this problem, wheelchairs, which are equipped with a power assist control system, are needed. In this research, the model based on the quantitative human-wheelchair system was proposed. In this paper, we considered about the coasting ability of this system and the braking performance with the use of hand-rims. The subject participated in a brake test in order to reduce braking distance by using the test machine that can provide an adjustment of inertia. The human characteristics in braking a wheelchair were described the influence of inertia to the braking performance.

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We propose the guidance control method to let a wheelchair follow an assistance dog by detecting relative velocity and angle between a wheelchair and an assistance dog. In this guidance control method, electric wheelchair employs the guidance unit that is composed of a long lead and a winder on the tip of left armrest. The tip of the lead is connected with the harness worn to an assistance dog. The length and the direction angle of the lead are detected by two potentiometers in the guidance unit Both translational signal and rotational signals to control the electric wheelchair are generated by these two detected information. In this report, we described an opinion about an adjustment of the control system, and the improving method of the rotational mobility of electric wheelchair by reducing translational velocity as the direction angle increase.

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The purpose of this study is to develop a wearable power assisting orthosis for nursing care. This orthosis targets at hold support within various nursing care. During hold support, care person uses both hands. That's why it's necessary for us to develop the hands-free control system In this paper, first, we analyzed hold support to realize the hands-free control system which use the electromyogram and the joint angle as control signal. From the result of analysis, we selected the electromyogram on supraspinatus muscle as a suitable control signal which applied a actuator. At the same time, selected the angle on elbow joint as a suitable control signal which stopped a actuator. By using these two signals, we realized the hands-free control system. At last, we ran the evaluation experiment to verify the effectiveness of the orthosis for hold support. From this result, it was confirmed.

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This paper deals with the support of sit-to-stand motion for supporting independence of the people with muscle weakness. Contrivance of rising motion which reduces physical work load is mentioned kinematically. First, kinematic conditions for rising are clarified by the experimental observation of sit-to-stand motion. Then the effectiveness of self-assistance in rising and care of rising is verified.

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The load of attendant's stopping operation on wheelchairs is very large because it is need that attendants must stop the wheelchair as soon as possible preventing from several danger situations. Our purpose is to develop the mechanical stopping assist for attendants, so we investigate the operation of attendant's stopping wheelchairs using motorized treadmill having feedback system to realize the load of wheelchairs. We carried out the stopping experiments with virtual wheelchair's mass from 20kg to 200kg on the treadmill and with the real wheelchair (100kg) on the ground. From the results, we found that the attendant's stopping distance becomes long, and the attendant's postures don't change for the mass.

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In this paper, We have developed the first robot which has 6-DOF and which provides effective rehabilitation program for upper limbs including wrists. This robot "SERAFY" is driven by ER actuators which has high performance in force display and ensures safety mechanically and quantitatively.

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We propose a rehabilitation by using efficient and safety rehabilitation robots in declining birthrate and an aging population. Three-dimensional six-degree of freedom rehabilitation robot for upper limbs and wrists together which we developed is world first. In this article we introduce the control system and application.

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This study investigates the optimal control of a marine propulsion system consisting of the engine, the propeller and the ship parts. First, each part of the system is analytically examined and the system is mathematically modeled. Then, dynamic characteristics of each subsystem are analyzed. Second, the performance criterion to characterize the system performance is defined so as to achieve the fast ship speed velocity under the constraint of engine torque limit and the procedure of optimal trajectory formation is developed. Third, a new control scheme is proposed in which the optimal trajectories are applied for actual control systems. Finally, advantages of the proposed control scheme have been discussed according to the simulation result.

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For second-order linear time-invariant systems which are not stabilizable via a single static output feedback, we consider a hybrid stabilization strategy. More precisely, we design two controllers and a conic switching law between the controllers so that the entire closed-loop system is asymptotically stable. We demonstrate the design method with various examples, and show that in some cases the stabilizability depends on the region of the initial state.

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This paper presents an improved identification scheme of AMB rotor system. First, this paper discusses the necessity of the closed-identification of AMB rotor system. Second, we propose a closed-loop identification method for MIMO system by combining the coprime factorization-based description. The most attractive feature is that it enables us to convert a closed-loop identification problem to an open-loop identification problem. Third, the numerical example demonstrates the effectiveness of the proposed method. Finally, we evaluate its effectiveness via identification experiments of AMB rotor system.

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