著者

森安 竜大 松森 唯益 永岡 真

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.854, pp.17-00144-17-00144, 2017 (Released:2017-10-25)

参考文献数

26

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A topology optimization method is proposed for the design of shallow-flow channels based on quasi-three-dimensional flow models of laminar and turbulent flows. The models for laminar flow and turbulent flow are derived from the Navier-Stokes equations and the Reynolds-Averaged Navier-Stokes (RANS) equations, respectively, by integrating along the direction of channel thickness. The thickness is employed as the design variable in the topology optimization. The design variables are updated using a time-dependent diffusion equation with a design sensitivity which is calculated by a discrete adjoint approach. Numerical examples for minimizing dissipation energy or variance of flow velocity magnitude using the topology optimization demonstrates that the proposed method is capable of finding optimal solutions that satisfy the KKT conditions. In the former example, the design domain was clearly divided into domains where the thickness was either near the upper limit or near the lower limit. However, in the latter example, the thickness was at an intermediate level in almost the whole the design domain. The distribution of the thickness varied depending on the Reynolds number in both examples.

著者

森安 竜大 若松 栄史 森永 英二 荒井 栄司 島田 茂樹 眞鍋 賢

出版者

一般社団法人 日本ロボット学会

雑誌

日本ロボット学会誌 (ISSN:02891824)

巻号頁・発行日

vol.30, no.8, pp.813-821, 2012 (Released:2012-11-15)

参考文献数

19

被引用文献数

1

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A modeling method to represent bending/torsional deformation of an electric wire is proposed based on the differential geometry. A twisted wire called a robot cable is used in a prismatic/rotational joint of an industrial robot to transmit signals or electric power. It is composed of a twisted bunch of several strands of many copper wires. The copper wire may be cracked by repeated bending/torsional deformation associated with the movement of a joint and such crack leads to wiring disconnection. To predict the life-cycle of the wires and to prevent such wiring disconnection, it is required to estimate deformation of not only the strands but also the copper wires when the wire is bent/twisted. In this paper, the deformed shape of a wire, which corresponds to a twisted bunch of n strands, is described by 3+2n independent variables and can be derived by minimizing the potential energy of each strand under various constraints. As the relationship between copper wires and their strand is similar with that between strands and their twisted bunch, the deformed shape of each copper wire can be also derived with the same method.