著者

高橋 辰伍 板野 健太郎 中本 圭一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.856, pp.17-00249-17-00249, 2017 (Released:2017-12-25)

参考文献数

13

被引用文献数

1

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Agile manufacturing that can rapidly machine advanced materials or creative shapes is expected as an important key to realize mass customization of industrial products. Most of high-value-added workpieces have three dimensional and complex shapes. Thus, the workpiece shape and stiffness vary greatly according to cutting procedure during a rough machining operation. The induced displacement of workpiece strongly affects machining accuracy and tool life. However, it is difficult to automatically determine the process planning in commercial CAM system because of a large number of combinations. Therefore, the process planning has been designed by skillful experts to achieve complex parts machining. In order to realize future high efficient machining, it is necessary to obtain these tacit knowledges and to formulate the implicit machining know-how owned by skillful experts. As the first step, a method is proposed to decide workpiece shapes during a rough machining operation to ensure the workpiece stiffness based on topology optimization in this study. Topology optimization that is known as one of the highly flexible structure optimization methods enables to deal with the target configuration and shape. By introducing changeable fixed design domain and discretized characteristic function, an optimization problem can be converted to a problem of material distribution. In this study, the topology optimization is applied to decide workpiece shapes during a rough machining operation. As a purpose of minimizing their mean compliance, the optimized workpiece shape is calculated depending on applied loads at each machining step. By using the calculated workpiece shapes, a case study of complex parts machining is conducted. From the result, it is confirmed that a rough machining operation of complex parts can be achieved according to the decided workpiece shapes.

著者

井上 友貴 中本 圭一

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.83, no.850, pp.16-00574-16-00574, 2017 (Released:2017-06-25)

参考文献数

7

被引用文献数

10

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Manufacturing industry tends toward high-mix low-volume production in recent years. Therefore, in the field of machining, the ratio of preparation in the lead-time becomes higher because the preparation takes a great deal of time and labor to decide suitable machining method, allocate target parts, select cutting tools and generate tool paths. As a result, it is strongly required to develop a computer aided process planning (CAPP) system to shorten the preparation time and to generate NC program. Feature recognition has been considered as a key technology to develop a CAPP system, and a lot of researches have been tackling the technology for a long time. In authors' previous study, novel machining features for multi-tasking machine tools have been proposed. The machining features can correspond to several alternative machining methods. However, complex target shapes of practical mechanical parts have not been considered. In order to solve this problem, special shapes such as chamfer part and freeform surface are firstly approximated and machining features are recognized by simplifying machining primitives such as complicated groove or taper shape. The machining primitives are finally restored to original complex shapes for CAM system in this study. From the results of conducted case study, it is recognized that the proposed feature recognition method has a potential to deal with complex target shapes of practical mechanical parts.