The number of people who are in need of nursing care due to difficulties they experience with performing various activities of daily living is increasing. In particular, the action of standing up is performed frequently in daily life, and this action starts to induce pain in joints as people age. In this research, we develop a device whose seat plate follows the movement of the thigh in the action of standing up for the purpose of relieving the burden from the joints and reducing the effort associated with nursing care. The device is designed by using a planar five-link mechanism and a gear train, and only a single input is needed to drive the device. The respective lengths of the links are determined by comparing the movement of the seat plate of the device with the movement of the human thigh in the action of standing up. In addition, this device is expected to be useful for assisting users in standing up in a natural manner, including in the case when the body remains supported by the seat plate, as well as for guiding the individual movements of users in the action of standing up.

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We presented a spatial parallel manipulator with redundant actuators for gross and fine motions to achieve fine positioning together with gross motion in three dimensional space. Four types of parallel mechanisms with redundancy for such a manipulator were proposed and their infinitesimal displacement characteristics were investigated. Of the four mechanisms, a mechanism was chosen, and a kinematic synthesis was carried out. A prototype parallel manipulator was designed and built based on the synthesis result. A control system to achieve a fine motion together with a gross motion and a procedure to determine desired input of gross and fine motion drive systems for a specified pose of the output link were presented. We showed experimental results of fine positioning achieved by our prototype manipulator. A high ratio greater than 10⁶ of total stroke of gross motion to positioning resolution and repeatability was achieved by our prototype manipulator.

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Trends of globalization and advances in Information Technology (IT) have created opportunity in collaborative manufacturing across national borders. A dynamic supply chain utilizes these advances to enable more flexibility in business cooperation. This research proposes a concurrent decision making framework for a three echelons dynamic supply chain model. The dynamic supply chain is formed by autonomous negotiation among agents based on multi agents approach. Instead of generating negotiation aspects (such as amount, price and due date) arbitrary, this framework proposes to utilize the information available at operational level of an organization in order to generate realistic negotiation aspect. The effectiveness of the proposed model is demonstrated by various case studies.

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Recently, several problems owing to electrical pitting have been observed to be extremely common in small bearings. Many researchers reported on the electrical pitting of bearings used for railcars. This paper deals with a fundamental experiment for electrical pitting in a small bearing (608). Experiments lasting 500 hours with conducting direct current between balls and raceways made it clear that the electrical pitting occurred at an electrical current density of about 0.04A/mm². This electrical current density was very small compared with that considered in conventional research.

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This paper deals with an experimental evaluation of bending fatigue strengths for hobbed, forged, sintered and austempered ductile iron (ADI) spur gears. The module is 2.5 and the number of teeth is 26 in the test gears. The materials of the test gears are SCr420H for hobbed and forged gears, prealloyed powder metal with 1.5 wt.% Mo for sintered gears, and FCAD 1100-15 for ADI gears. All gears except ADI gears were carburized. The pulsator bending fatigue tests were carried out for the test gears. Then the relationship between the strength and the manufacturing cost is obtained. The forged gear has the high strength of 3% and low cost compared with the hobbed gear. It is the best among the four gears. The sintered and ADI gears have approximately half the strength and cost of the hobbed gear. These gears are effective when cost is a high priority. In the progress of the fatigue tests, comparisons of strength among gears having different tooth-root forms were needed. The nominal stress obtained from actual measured profile data using a noncontact-type measuring machine is suitable for comparing the fatigue strength in gears having different root forms.

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A robust measurement method for measuring the vertex position of a small polyhedron using 3D image processing is proposed. The shape from focus method is applied for obtaining 3D positions of surfaces of the polyhedron. The in-focus function is usually averaged for reducing noise, but the resultant function lacks sharp edge information of the target. The position of the vertex is indirectly calculated from 3D data using the geometrical model of the polyhedron. In this study, relationships between measurement noise and (a) the appropriate number of data values required for averaging of focal measurement and (b) the area of data fitted by the Gaussian function are investigated. Then, error propagation analysis is applied to the equations of the indirect measurement of the vertex position. By using the geometrical characteristics of the polyhedron, the vertex position measurement is made robust against measurement errors. The effectiveness of the proposed method is confirmed by numerical simulations and experiments.

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The module structured production systems that aim for the demand-synchronized production has a function and composition for high-variety low-volume production. However, an efficient dispatching to manufacturing lines is a problem to be solved. Two requirements are necessary for the dispatching order system to solve this problem. The first requirement is that production order must be decided with parameters of evaluation values that affect efficiency. For quick response to actual orders and variable conditions of manufacturing lines, deciding a production order with short processing time would be essential. And the second requirement is to decide a production order in short time by grasping condition changes of actual orders and variable conditions of manufacturing lines in real time. In this paper, we propose a configuration and operation systems that efficiently dispatch orders by grasping actual conditions of manufacturing lines in real time for meeting customers' various demands. Effectiveness of the system is verified with examples.

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In this paper the knowledge discovery technique is used to build an effective and transparent mathematic thermal error model for machine tools. Our proposed thermal error modeling methodology (called KRL) integrates the schemes of K-means theory (KM), rough-set theory (RS), and linear regression model (LR). First, to explore the machine tool's thermal behavior, an integrated system is designed to simultaneously measure the temperature ascents at selected characteristic points and the thermal deformations at spindle nose under suitable real machining conditions. Second, the obtained data are classified by the KM method, further reduced by the RS scheme, and a linear thermal error model is established by the LR technique. To evaluate the performance of our proposed model, an adaptive neural fuzzy inference system (ANFIS) thermal error model is introduced for comparison. Finally, a verification experiment is carried out and results reveal that the proposed KRL model is effective in predicting thermal behavior in machine tools. Our proposed KRL model is transparent, easily understood by users, and can be easily programmed or modified for different machining conditions.

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Recently, sustainable materials have attracted attention because of the need to alleviate environmental problems. Bamboo, in particular, has attracted attention as a sustainable material because it has the fastest natural growth rate among various natural materials. A self-bonding fiberboard using high quality bamboo fiber extracted with a machining center has been enabled to be fabricated by hot press forming. Therefore, we propose a sustainable manufacturing system that focuses on bamboo. An environmental impact of our system was evaluated by life cycle assessment (LCA), comparing with a glass fiber reinforced plastic production. Additionally, based on the LCA result, higher efficient fiber extraction process was proposed by an application of in-situ measurement of uninformed bamboo shape with irregularity.

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This study focuses on single point micro incremental forming (SPMIF) applied to the forming of miniature shell products in meso-scale. For this study, a desk-top type of CNC forming machine was newly constructed as an experimental apparatus. A thin aluminum foil with a thickness of 12 µm and a thin round-tip bar with a radius of 100 µm were utilized as a blank and a forming tool, respectively. Some fundamental and complex shell structures were formed for investigating the characteristics of the SPMIF process without using any die and backing plate. The analysis of contact region in forming polygonal pyramids confirmed that fracture on an edge of a polygonal pyramid, which determined the forming limit of SPMIF, was strongly affected by the size of re-contact area. Through the SPMIF process established in this study, complex shell structures were accomplished with elaborate tool paths.

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