多相低自由度空間機構之合成與探討

CCUR > College of Natural Science and Engineering > College of Engineering > Department of Mechanical Engineering > project > Item 987654321/30517

Please use this identifier to cite or link to this item: https://irlib.pccu.edu.tw/handle/987654321/30517

Title:	多相低自由度空間機構之合成與探討 The Synthesis and Investigation of Multi-Phase Low-Degrees-Of-Freedom Spatial Mechanisms
Authors:	鐘文遠
Contributors:	機械工程學系
Keywords:	多相機構低自由度複合式平台物體導引路徑演生構形分支缺陷次序缺陷
Date:	2015-08
Issue Date:	2015-09-08 13:17:51 (UTC+8)
Abstract:	本計畫針對具單一個自由度的三維機構進行探討，使其藉由桿長或固定樞點的調整，可演生兩相不同的路徑。機構主要由固定底座、移動平台及數組支撐腿所組成。其自由度取決於支撐腿的數目和支撐腿兩端接頭的類型；經評估篩選後，選擇UR-2SS來執行雙向路徑演生。UR-2SS機構的主要特徵為給定U接頭的第一軸角度後，該機構可類比於Assur五連桿組，有利於構形及分支的分析。對分支缺陷提出兩種必要條件，以利棄除不當的設計。當固定樞點可調整且桿長維持不變時，兩相的精確點指定總數最大值為10。本計畫成功演生兩組各含四個精確點的路徑、各含五個及四個精確點的路徑、以及演生皆含五個精確點的路徑。若僅藉由桿長的調整而固定樞點維持不變，兩相的精確點指定總數最大值為8。除了成功演生分別經過四個與三個精確點的路徑，亦完成各含四個精確點的路徑，以及各含五個與三個精確點的路徑。對於各類精確點的指定，本報告揭示其合成的程序、分支缺陷的評估與目標函數的規劃，並有數值例題加以說明。本研究的成果，可讓低自由度三維機構能符合較多精確點的指定，使其功能及效用能進一步充分發揮及提昇。對於本報告所敘述的各類例題，其程式皆已用Matlab開發完妥。使用者只要輸入精確點的座標，可得知路徑是否須調整，或者尋得適當的機構以演生指定的路徑，並選用3D設計軟體加以模擬。適合供產業界參考使用。 In this project, three-dimension mechanism with one degree of freedom is investigated in order to generate two paths by means of adjusting link lengths or the positions of fixed pivots. The mechanism consists of fixed base, moving platform and several supporting legs. The degree of freedom depends on the number of supporting legs and the types of joints on both ends of each leg. The UR-2SS is selected to execute two-phase path generation. A special feature is that this mechanism can be analogous to a planar Assur kinematic chain for any given input angle, and the configurations can thus be analyzed successfully. Two necessary conditions are proposed to get rid of any branch-defect mechanisms. If the lengths of supporting legs remain the same and the positions of fixed pivots are adjustable, the maximum number of precision points that can be assigned is 10. Three cases of different assignments are discussed. The numbers of precision points for both paths are 4 and 4, 5 and 4, and 5 and 5. If only the lengths of supporting legs are adjustable, at most 8 precision points can be assigned. The numbers of precision points of discussed cases are 4 and 3, 4 and 4, and 5 and 3. The process of synthesis, planning of objective functions, evaluation of branch defect, and performance of the mechanism are all illustrated in numerical examples. The achievement of this project significantly increases the number of precision points that can be assigned. The function of this proposed mechanism is thus promoted and its utility can be enhanced. The programs are developed by using Matlab for all cases. After assigning the precision points, the program can search any suitable mechanisms. The paths have to be adjusted if no mechanisms can be found. The synthesized mechanisms can also be animated with 3D design software to validate its performance and clarify the problem of branch-defect. The results and programs developed in the project are thus suitable to be used or referred by industry.
Appears in Collections:	[Department of Mechanical Engineering ] project

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	392	View/Open

View Licence

Loading...