機械手指抓取之有限元素分析

Finite Element Analysis of Robot Finger Grasping

陳政瑋(Jheng-Wei Chen)

指導教授 ： 劉昭華

淡江大學/工學院/機械與機電工程學系碩士班/碩士(2013年)

https://doi.org/10.6846/TKU.2013.01153

摘要

本論文探討機械手指夾取圓柱的接觸問題，利用套裝軟體ANSYS從事有限元素接觸分析，本文先進行圓柱與平面以及圓球與平面的接觸分析，數值結果先與赫氏接觸之解析解比較，再進行機械手指夾取圓柱的接觸分析。
分析的情況包括兩個部分，第一部分是針對手指以平移方式夾緊圓柱，而二部分是機械手指用旋轉的方式夾取圓柱。在第一部分機械手指可以有傾斜角度，並以平移方式夾取圓柱，本文求出不同傾斜角度情況下夾緊位移與正向力之間的關係；以及機械手指夾取不同材料圓柱時夾緊位移與正向力之間的關係；並探討手指夾取鋁製圓柱的降伏問題。本文第二部分首先推導出模擬旋轉夾緊的位移邊界條件，利用此條件所求出的有限元素分析結果非常接近利用材料力學懸臂樑公式求出的估計值。

關鍵字

接觸分析 ； 有限元素法 ； 機械手指

並列摘要

Contact analysis in robot grasping is performed in this thesis. Commercial software ANSYS is used in finite element analysis. Two dimensional cylindrical contact analysis and axisymmetric spherical contact analysis are first performed, and the results are compared to Hertz solutions.
Then two situations are treated in this study: cases with linear tightening displacements and cases with rotational tightening displacements. In the first situation, translational tightening displacements may be imposed by inclined robot fingers. The relation between normal grasping force and linear tightening displacements are obtained for various inclination angles of the fingers, and for cylinders with various material properties. Also the critical linear displacement that causes yielding is obtained for an Aluminum cylinder. In the second situation, displacement boundary conditions to simulate rotational tightening are obtained. Results obtained by imposing these conditions agree well with estimated values found by using fixed-end beam formula.

並列關鍵字

Contact analysis ； Finite element analysis ； Robot fingers

參考文獻

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