著者

關口 隆弘 村上 岩範 都丸 瞬 後藤 桂孝 吉澤 明訓

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2008, pp."653-1"-"653-6", 2008-09-02

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In this research, it proposes the development of High-Tc Superconducting Levitation flywheel. The permanent magnet magnetized in the thickness direction where the sectorial magnetic material plate is adsorbed creates the multipole field outside of the magnet. The levitation body achieved the stable rotation without the control by giving the driving force from the axial direction to the multipole field of the levitation body, and thus it succeeded in riding past the resonance. And, the voltage correction that considered the counter-electromotive force and impedance was executed so that this system might obtain the stable torque. As a result of measurement of electric power generation at the high-speed rotation region, it was confirmed that this system had about 84% conversion efficiencies. The result of the experiment and the theoretical value of the magnetic flux density, the torque, the frequency response, and the conversion efficiency of this system were compared. As a result, because measurements and the analytic value were corresponding well, it was confirmed that this analysis was useful.

著者

渡邉 尚彦 川口 健一

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2006, pp."662-1"-"662-6", 2006-08-06

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The "Origamic" approach gives us useful information and suggestion in the design of folding pattern of membrane, which can be applied to retractable membrane roof or foldable membrane structures. In the Origamic approach, membrane is assumed that it has perfect shear rigidity and its flexural deformation occurs only along the crease line. In the paper extraction of basic folding pattern from eigen modes of bending deformation is firstly proposed. Then the condition of foldability and its applications to the generation of foldable pattern in the finite displacement range are also proposed. Finally the patterns and conditions are examined by folding analysis.

著者

胡 亜波 趙 希禄 萩原 一郎

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2009, pp."531-1"-"531-5", 2009-08-03

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In recent years, the structures which used origami engineering attract much attention. It can be applied in many fields, such as automobile, building, medical care and so on. In this paper, it is focused on the reversed spiral cylindrical (RSC) origami structure, which is designed by Nojima. This structure is expected to use in side member and beverage containers. An automatic crashworthiness analysis system is developed to generalize different types of RSC origami structures which can transform RSC origami structures from polygon thin wall structures with a group of parameters automatically.

著者

西沢 祐介 田中 寛人 吉田 勝俊 佐藤 啓仁

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2006, pp."108-1"-"108-5", 2006-08-06

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非線形振動系とその複製に共通の不規則外乱を与えると,両者の応答が同期する現象が知られている.任意の初期値から同期状態へ到達するまでの収束時間は,パラメータ条件の選び方に大きく依存するが,未検討である.そこで本報では,このような収束時間のパラメータ依存性を,統計的等価線形化法によって定量評価してみる.具体例として,ランダム調和入力を受ける系(式(Al))と,狭帯域ランダム入力を受ける系(式(A2))を取り上げる.x+cx+kG(x_0+x;μ)=Q+P_<cos>(ωt)+sw(t) (A1) {x+cx+kG(X_0+x;μ)=Q+F(t) F+2ζω_nF+ω^2_nF=sw(t) (A2) G(x_0+x;μ)={x_0+x+μ (x_0+x&le;-μ) 0 (-μ<x_0+x<μ) x_0+x-μ (x_0+x&ge;μ)以下の数値例では,式(A1)に対してc=0.04, k=1,0, Q=0.3, P=0.2,μ=0.7, s=0.02とする.図A1は,式(A1)から求めた同期誤差の見本過程の一例を表わす.ω=1.07に対する図A1の(a)の結果では同期までの収束時間はT=195程度だが,ω=0.81に対する図A1の(b)では, T=18973程度を要する.このように,同期に至る収束時間にはパラメータ依存性がある.同期可能なパラメータを推定する常套手段として,式(A1)の系の最大リアプノフ指数を入力周波数ωの関数としてプロットしたのが図A2である.先ほどの条件ω=1.07,0.81に対する最大リアプノフ指数はそれぞれλ&ap;-0.102,-0.101となり,収束時間の変化は捉えられない.そこで,積率微分方程式を用いて式(A1)の分散応答を求めた結果を図A3の上段に示す.ω=0.77,0.92を跳躍点とする跳躍履歴現象が見られる.図A1の収束時間と比較すると,収束時間が短い条件ω=1.07は跳躍履歴現象の外部に位置し,収束時間が長い条件ω=0.81では内部に位置している.すなわち,積率微分方程式の跳躍履歴現象の有無によって,同期への収束時間を評価できる可能性が明らかになった.この仮説を確かめるため,図A3の下段に,サンプルiの初期値x_kに対する収束時間をT_i(x_k)とするときの平均収束時間〈T>= 1/(MN)Σ^M_<i=1>Σ^N_<k=1> T_i(x_k)を示す..M=100, N=5×5とした.収束時間が長い条件ω=0.81は,積率微分方程式の跳躍履歴現象の発生領域に含まれており,式(A1)の積率微分方程式の跳躍履歴現象は,同期の収束性が悪化するための十分条件を与えている.なお,式(A2)の場合には逆に必要条件を与える.

著者

今西 悦二郎 南條 孝夫 廣岡 栄子 井上 喜雄

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2004, pp."417-1"-"417-6", 2004-09-27

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Dynamic simulation of flexible multibody system with the hydraulic drive is presented for the digging operation of the hydraulic excavator. The energy saving technology is required on the construction machinery design from the present environmental point of view, and the dynamic simulation is useful for the energy saving evaluation. The digging operation of the hydraulic excavator involves the dynamics of linkage system and the hydraulic drive system that includes nonlinear characteristics such as the check valve and so on. New numerical analysis method is presented for the coupling system of the linkage system and the hydraulic system, which consists of the time increment prediction method on piecewise-linear characteristics and the bisection method in Newton method. It is shown that this method is useful for the dynamic simulation of the flexible multibody system with the hydraulic drive by appling to the simulation of digging operation on the hydraulic excavator.

著者

松本 興助 有井 士郎 田邉 博典 水本 洋

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2004, pp."418-1"-"418-5", 2004-09-27

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This paper deals with two types of trajectory planning method for three-link flexible arms. By using the desired trajectories obtained by the proposed methods, the flexible arms can rotate from each initial position to desired locations in given movement execution time without large troublesome vibrations. And additional feedback control devices besides the controller of existing actuators are not necessary. In order to confirm the effect of the desired trajectories on reducing the vibrations of the flexible arms, the responses of the three-link flexible arms were simulated numerically. It can be seen from the numerical results that the vibrations of the flexible arms were reduced enough by using the desired trajectories.

著者

中村 肇 金光 陽一 雉本 信哉 松田 浩一 河島 浩一

出版者

一般社団法人日本機械学会

雑誌

Dynamics & Design Conference

巻号頁・発行日

vol.2003, pp."150-1"-"150-6", 2003-09-16

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We are developing an electromagnetically levitated vibration isolationsystem for micro vibration isolation. It supports a floating isolationtable without any mechanical contact by using active magnetic bearings to reduce vibration from a floor. The system aims to regulate the microvibration in 6 degree of freedom. Two kinds of controller are designed and confirmed to levitate the table stably by experiments. A series of simulation show that the controllers have good effect on the vibration isolation.