A new accurate simulation method for mass evacuation using precise human joint models has been developed. To realize more accurate as well as realistic evacuation simulation, first, an adequate parallel programming platform using multi-agent concept has been developed. Second, a precise human body model representing real evacuator has been introduced to improve the accuracy of the evacuation simulation. Then, several significant motion primitives such as go-down stairs motion, strictly necessary for the evacuation, have been derived. Finally, comparing the developed simulation results with real evacuation drill result, the effectiveness of the proposed method for mass evacuation simulation has been clarified.

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This paper deals with investigation to determine optimum seat belt characteristics in order to reduce occupant injuries for frontal impact of vehicle at the primary design phase. The first purpose of this investigation is to calculate occupant chest deceleration under one degree of freedom spring and mass model which includes seat belt slack and preload when subjected to half-sine frontal crash pulse. Next we conducted half-sine vehicle acceleration curve sled test for frontal impact under the Hybrid III dummy restrained by the various type of seat belt. In all six comparative test cases, maximum chest deceleration between calculated value and tested value have relatively good compatibility. This paper indicates that the present method can be estimated the maximum effects of a pretensioner as for the relative comparison of occupant chest deceleration when the T.T.F. (Time to Fire) of seat belt pretensioner or force of preload changes.

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Rolling stock has generally been inspected and maintained on the basis of preventive maintenance. However, the reliability of sensors and information technology have drastically improved and, with this background, the objective of this research is to develop a condition monitoring system for the bogies of Shinkansen cars. This paper describes two algorithms for detecting faults in some parts of bogies. These algorithms are based on the statistical analysis of vibration acceleration. One algorithm compares the vibration states between the front and rear bogies in the same car when one bogie has faulty parts. The other algorithm detects the signs of faults by examining the amplitude and duration of the peaks of measured vibration acceleration. Through the experiments simulating some faults in bogie parts and analysis, we can demonstrate the reliability of the schemes developed in this study for monitoring the conditions of Shinkansen bogies.

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The water jet dismantling method without damaging of the Light Gauge Steel (LGS) was proposed to remove the ceiling plaster board instead of the conventional manual method. The water jet from the nozzle that is installed to the manipulator tool cuts the plaster board. The plaster board is cut under the center of the LGS including the screw bolt attaching the board to the LGS. After cutting, the plaster board can be removed easily when it is pulled on with a little amount of force. This paper shows cutting conditions and development of high-speed dismantlement methods for reusing or processing based on some experiments for the ceiling plasterboard. The 4 axis manipulator with water hydraulic actuator and robotic system were also proposed and evaluated the effectiveness of the target and task needs.

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For demand-synchronized production, it is essential to secure manufacturing lines and facility to be required and keep required components on a steady basis. To achieve this, predicting the peak of future order is the key. Proposed on this paper is a method to predict future production volumes from the results of analysis of the past order data and determination of their similarity by Fourier analysis. When we examined a production forecast using the actual data, the peak-to-valley match rates, which indicate agreement with order peaks, were raised to a significant level. As a result, we can say it is possible to predict required production volumes in several days advance with sufficient accuracy. Wasted inventories could be decreased by better component arrangement. Furthermore, manufacturing facility could be arranged earlier and production load could be effectively adjusted with other manufacturing lines. Efficiency of the manufacturing facility in the entire factory would be largely increased.

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PTFE (Polytetrafluoroethylene) gasket is recently widely used as a substitute of compressed asbestos sheet gasket. Even though the PTFE gasket has excellent seal performance, heat resistance, and chemical resistance, a large reduction of axial bolt force under high temperature condition is a serious problem for a bolted connection with PTFE gasket. What is a dominant factor for bolt force reduction in the connection is not clear because of complex high temperature performance of such soft gasket. In this study, finite element simulations to investigate axial bolt force reduction of single bolt connection with soft gasket are performed under some temperature conditions, where temperature and time dependent gasket material properties, such as stress-strain relation, thermal expansion factor and creep performance, are measured and employed. As a result, we can confirm the validity of the finite element simulation by comparing numerical and experimental results of time changes of axial bolt force. Furthermore, to specify the dominant factor of gasket performance for bolt force reduction, the finite element simulations are conducted. It is concluded that temperature dependent stress-strain relationship and creep performance of gasket are the most dominant factors for bolt force reduction at unsteady and steady state conditions, respectively.

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In escalators that drive the handrail with driving rollers, small diameter rollers push against the handrail surface for extended periods of time when the escalator is not in operation. As a result, indentations remain on the handrail surface and the handrail surface is easily covered with dirt. Since the holding force or driving force, per roller is limited, it is necessary to increase the number of handrail drive devices in proportion to the height of the escalator. This results in increased costs. A handrail drive device that has a variable holding force can resolve these issues. This type of handrail drive device drives the handrail with driving rollers, but the holding force changes in proportion to the running resistance of the handrail, and the holding force is very small when the handrail is stopped. Accordingly, there will be less dirt accumulation and indentations on the handrail, and the number of handrail drive devices need not be increased for a high escalator. Handrail drive devices with variable holding force are already commercially available and the basic operating principles are known. However, apparently there is no written report covering the detailed operating principles, and experimental verification of the performance of these handrail drive devices. In this paper, first the operating principles are reviewed. Next, the relation between the running resistance of the handrail and the holding force is examined when the inclination of three driving rollers are and are not compensated to maintain horizontal alignment. In addition, a handrail drive device and a pilot machine were built to evaluate performance and to verify the operating principles.

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A vibration reduction method that involves installing two flexible joints in series has been found to be useful for countermeasures against structure-borne sound in pump piping system. However, it has the practical difficulty that the pipe's vibration mode must be measured many times for determining the optimum location of flexible joints. Therefore, we newly propose the technique using two flexible joints and a rigid disk in order to improve the practicality of the previous method. In the present method, two flexible joints are first installed anywhere on the piping near the pump, and a rigid disk is then mounted on the piping between the pump and the flexible joint. Then, the pipe vibration can be easily reduced by just adjusting the location of the rigid disk without measuring the pipe's vibration mode. In this paper, the influence of underwater sound is neglected for simplify and the effectiveness of the present method in reducing vibration in straight-line piping is investigated analytically and experimentally. The results of the numerical analyses and experiments confirm that the present method is excellent in terms of usefulness and can achieve the vibration reduction effect comparable to the previous method.

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This paper deals with active noise control based upon a virtual sensing, which does not require a reference signal of a primary sound source, hence termed non-reference virtual sensing ANC. There is thus no need to place an error sensor and a reference sensor at a control point and a primary sound source, respectively. Firstly, the principle of a virtual sensing is presented, followed by that of the estimation of a primary sound source frequency. For the purpose of enhancing the virtual sensing estimate, four sound sensors are employed, two of which are used for estimating the targeted sound amplitude and the others for minimizing the estimate error. Using the four sound sensors, the phase estimate of a virtual sensor output is also conducted, the algorithm for further improving the phase estimate being proposed. Finally, an experiment is carried out, verifying the validity of the non-reference virtual sensing ANC.

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In this paper, we propose a design method of a static anti-windup compensator in order to improve tracking performance. A new L_2 gain performance index that includes not only plant state but also controller state is introduced, and a design procedure based on linear matrix inequality is developed. It is demonstrated by the angular control of a belt-drive system that a good tracking performance is attained by tuning the weights on the states of the performance index.

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A new flywheel Uninterruptible Power Supply (UPS) capable of providing 200kW electric power within 20 seconds have been produced using small homo-polar magnetic bearings with zeropower control which is essentially the same control as previously reported. This flywheel rotated in a vacuum chamber is made of Carbon Fiber Reinforced Plastics (CFRP). It is important to maintain eddy current loss at low level, because rotor temperature rise causes deterioration of strength of CFRP. In this study relationship between rotor temperature and calorific value by the eddy current loss has been predicted and it has had a good agreement with the experimental results. Further the vibration characteristics of the flywheel UPS has been investigated by analysis and experiment. Consequently a loss as low as 16W at a speed of 13000min^<-1> has been achieved. Operation for as long as 1000 hours is possible with no significant rise in temperature.

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This paper describes comparison between the emergent design system and the topology optimization method to aim at showing a guideline for application of the emergent design system in a structural design problem. The emergent design system is a design system based on concept of emergence, and can derive diverse solutions under few design conditions. In the present study, a comparison of derived solutions by the emergent design system and the topology optimization method was carried out in two-dimensional cantilever beam design problem which is a basic structural design problem. As a result, including solutions, which is better than a derived solution by the topology optimization method in the stiffness and strength, in derived diverse solutions by the emergent design system, and a guideline for application of the emergent design system in a structural design problem were shown.

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In order to understand the mechanism of toner scattering in multi-transfer process of electrophotography, an observation and a simulation of toner behavior in the transfer process between parallel plates are carried out. It is clarified that toner particles are scattered from a transferred toner layer in the separating process of the parallel plates. Since the calculated toner behavior corresponds to the observed toner behavior, the calculation model of toner scattering is validated. The model experiment and the simulation with some combination of transfer parameters are carried out and the quantitative relationship between the number of toner scatterings and the transfer parameters is obtained.

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The objective of this study was to propose the mechanically optimal walking form in water for muscle training. First, the evaluation index for the muscle training and the penalty index for the joint load were defined, according to the definition of the optimal walking form. Second, ten walking forms were analyzed by our developed simulation model for walking in water. From the analysis, two forms accompanying the large joint motions of the hip and knee were selected as the optimal forms by comparing the evaluation and penalty indices. Since these forms are suitable for both the hip flexor and knee extensor in forward walking, and are suitable for both the hip extensor and knee flexor in backward walking, it is especially effective for balanced muscle strengthening to walk both forward and backward.

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In recent years, many caregivers adopt the concept of Body Mechanics as the one of nursing care technique, for example Kinaestetik, Nursing Biomechanics, and so on. The concept is defined as the support of Patients' natural movement. We take Body Mechanics as the ergonomic method, and propose the method for quantitative analysis of both a patient and a caregiver. In this article, we proposed the transfer assist equipment based on Body Mechanics and demonstrated the effectiveness of the equipment.

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In order to make space missions successful reliably and safely, numerical dynamics simulation is important. In the simulation, identifying the contact force model and parameters is a key issue. In general, the identification experiment of space systems on the ground is difficult because of the gravity. This paper describes a strategy for identifying the contact parameters using a hybrid simulator. The hybrid simulator includes fatal control time delay which varies the contact force. However, the contact parameter can be identified by comparing the results of the hybrid simulation and pure numerical simulations including a time delay model. In this method, that the control time delay has little influence on the determination of contact parameters. In this paper, the dynamics model, including the time delay that exists in a hybrid simulator, is studied in detail. For verification of this method, the determined contact parameters are compared with the result of the contact experiments with a real floating object.

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In this study, we pay attention to braking action in the emergency case and measure the driver's action characteristics in various conditions of pedal placement. Experimental results suggested that 1) in back condition Movement time and Moving time get shorter and the maximum displacement to peak value of the joint angle decreases, 2) in front condition Releasing time get shorter and the maximum displacement to peak value of the joint angle increases. Based on experimental results, we recommend that the most suitable horizontal placement of brake pedal may set between 50mm and 100mm to accelerator pedal. In addition, the depth placement of brake pedal may set between 0mm and 100mm to accelerator pedal.

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The estimation of steering characteristics such as steering feel by using only computer simulation technology is extremely difficult. To solve this problem, a steering simulator referred to as "Hard-in-the Loop" has been developed by researchers, in which the steering reaction force on the tie rod is produced by an AC servo motor and a ball screw, assuming mathematical models of the vehicle and tires are known. The purpose of this study is to develop a more simplified steering simulator, in which the electric motor in the EPS produces steering reaction torque and conventional assist torque. In this paper, emphasis is placed on the validity of this proposed means of generating steering reaction torque. The usefulness of this steering simulator was ascertained by comparing the test results of the simulator with the results obtained from computer simulation and actual vehicle testing.

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This research discusses an optimal design problem for product family deployment under a wider perspective throughout commonalization, customization and lineup arrangement. In the discussion, commonalization is viewed as the operation that restricts the feasible region by fixing a set of design variables related to commonalized components or modules, customization is viewed as the operation that adjusts another set of design variables related to reserved freedom, and lineup arrangement toward individual customer's needs is possible within ones that are feasible under commonalization and customization. This paper defines the mathematical fundamentals of the design problem throughout these aspects under the viewpoint of optimal design paradigm. That is, the mathematical formulation is generally defined, its mathematical structure is revealed with a concept of active set strategy, and the modes of the optimal solution are explored toward developing any computational approach for effectively solving such complex design problems. Finally, a case study is demonstrated with a design problem of product family deployment of centrifugal compressors for illustrating the optimality in the throughout design.

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In order to examine the effects of the D-value and the hardness on the pitting fatigue life and the surface durability synthetically, data from 38 series of roller tests and 2 series of gear tests which were conducted under a sliding-rolling contact condition with various lubricating oils using various specimens with different hardness of HV170 to HV540 finished by various methods are considered in this paper. It is consequently clarified that the surface durability is proportional to the hardness and this tendency is changed by the surface roughness and the D-value, the relationship between the D-value and the pitting fatigue life N is not absolute with some dispersion even under the same hardness condition, the D-value at endurance limit, i.e., D_<lim> tends to increase as the hardness and the surface roughness increase, and as to an equation of σ_<Hlim>=aD_<lim>^<3.85> between the Hertzian stress at endurance limit σ_<Hlim> and the D_<lim> introduced by the defined equations of the Hertzian stress and the D-value, value of a tends to decrease as the hardness and the surface roughness increase.

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A miniature mechanical seal with the cooling water circulating system have been developed as a solution of the shaft seal problems in rotary blood pumps. The present paper describes the effect of the surface roughness in the sealing gap on the shaft seal problems under blood sealing. The sealing surface roughness of tested three seat rings were designed to be Ra=0.009μm, Ra=0.088μm and Ra=0.170μm. The frictional loss torque in the sealing gap and the leakage of the blood and the cooling water were measured in this work. Results show that the maximum frictional loss torque measured in the seat ring of Ra=0.009μm, and the frictional loss torque decreased as the surface roughness increased. The leakage rate of the cooling water is larger than that of the blood in all seat rings, even though the blood chamber has higher pressure. The sealing characteristics between under blood and water sealing were different. Moreover, the best surface roughness in the torque and the leakage characteristics were also different. Thus, it is important to study under blood sealing in the design of the surface roughness of the mechanical seals for rotary blood pumps.

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We have been developing a new tissue engineering technique for cartilage repair using a scaffold-free tissue engineered construct (TEC) bio-synthesized from synovium-derived mesenchymal stem cells. A round-chondral defect of 8.5mm in diameter and 1.5mm in depth created on the medial condyle of 12 month-old mature porcine femur was filled with the TEC. Six months after surgery, a cylindrically shaped specimen of 4mm in diameter and 4-5mm in depth was extracted. Micro-indentation test was performed on the specimen using an AFM after the surface image of the specimen was obtained. Macro-scale compression test was, then, performed for the specimen using a custom made micro compression tester. As compared with many bump-like elevated portions of approximately 1-2μm in height observed in the surface of normal cartilage, rougher surface was observed in the TEC-treated and TEC-untreated tissues. The surface stiffness of the TEC-treated tissue was significantly lower than that of the normal cartilage, and slightly lower than that of the TEC-untreated tissue with no significant difference. In the quasi-static compression test, the tangent modulus of the TEC-treated tissue indicated no significant difference against the normal cartilage. In contrast, the tangent modulus of the TEC-untreated tissue was lower than those of the normal cartilage and the TEC-treated tissue, with a significant difference against the normal cartilage. It is suggested that the surface stiffness was independent of treatment of TEC, while the bulk modulus recovered well in the TEC-treated cartilage-like tissues as compared with the TEC-untreated cartilage-like tissues.

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Servo control is one of foundamental control techniques for control problems of many mechanical structures. Various kinds of control methods such as PID, LQ and H-infinity controls have been applied to active servo control designs. However, it is very important to guarantee against safety in the control problems of man-machine systems. Especially, driving recklessly due to software or hardware errors in active control systems must be avoided in some devices, e.g., nursing care or medical devices. Therefore, an intrinsically safe control system is required for the devices. This note discusses the use of an intrinsically safe servo control system consisting of passive elements instead of active actuators. For such a control system, semi-active control to vary passive parameters such as viscous damping is important. Therefore, a novel servo control method based on the bilinear optimal control theory is proposed for the system in this note. The effectiveness of the method is verified by simulations.

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In this study, to obtain the high joint strength in riveting of dissimilar sheet metals, the riveting process with a washer was applied to joining. First, both the rivet joints between aluminum and steel with a washer and without it were produced. Next, tensile tests of the joints were carried out and fracture aspects of the joints were investigated in detail, and their joint strength was examined. From the obtained results, it was clarified that fracture aspects of the joints were influenced by the existence of a washer and the joint strength with a washer is higher. It is also confirmed that the riveting process with the washer was effective for joining of dissimilar sheet metals.

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