以向量式有限元素法分析具間隙撓性連桿機構

Dynamic Analysis of Flexible Mechanisms with Clearance Using Vector Form Intrinsic Finite Element Method

李昆晃(Kun-Huang Lee)

指導教授 ： 李志中

共同指導教授 ： 吳東岳

國立臺灣大學/工學院/機械工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.01309

摘要

機構中所使用的接頭因為加工誤差或熱膨脹等因素產生間隙，間隙會導致接頭在運動的過程中產生分離，衝擊等現象，造成機台壽命降低、振動增加與輸出誤差。本文主旨在於應用向量式有限元素法及彈簧阻尼法(Spring Dashpot Approach)模擬具間隙撓性桿件機構，並探討具間隙撓性連桿機構之動態特性。具間隙撓性連桿在運動的過程中，有穿透，撞擊等現象，而向量式有限元素之優點正在於可以處理桿件運動過程經歷大的幾何變形，如破裂，穿透，撞擊，或非線性的材料性質，因此我們選用向量式有限元素來模擬具間隙之撓性連桿。

關鍵字

向量式有限元素法 ； 撓性 ； 連桿機構 ； 間隙

並列摘要

Most of the time, inaccurate machining and heat expansion will cause clearance to exist in the joint. The existence of the clearance increases the impact force that the joint has to sustain due to the phenomenon like separation and impact happen in the kinematical process. Those effects will shorten the joint’s life and increase the vibration of the machine, which then causes the error on machine’s output. In this thesis, the dynamic analysis of flexible mechanisms with clearance using vector form intrinsic finite element (VFIFE) method and Spring Dashpot Approach is performed.
We choose VFIFE to analyse flexible machine with clearance because VFIFE is good for handle large deformation.

並列關鍵字

VFIFE ； Clearance ； Flexible link ； Joint

參考文獻

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