| Summary: | 碩士 === 國立成功大學 === 機械工程學系碩博士班 === 100 === This thesis takes advantage of theories in planar kinematics and extends them to their counterparts in spatial kinematics. It is known that the pole in planar synthesis theory is the degeneration of the screw in spatial kinematics. This thesis seeks to find the spatial generalizations of curves arising in the motion of a planar double-slider linkage, such as the circles of moving/fixed centrodes, the circles of rotation curves, and the circles for three-position synthesis of sliders and inverted sliders.
For Spatial mechanisms, we use screw to describe the motion of rigid bodies. A screw used in instantaneous situation is called instantaneous screw. The locus of all instantaneous screws of a single degree-of-freedom motion is an instantaneous screw surface. A screw used in finite displacement is called rotation screw. The locus of all rotation screws is a rotation screw surface. For three-position synthesis of the spatial double-slider linkage, we obtain a double infinity of screw axes.
We investigate the motion of a special RCCC linkage. For the RC and CC dyad, joint axes of each dyad intersect perpendicularly. Various screw surfaces have been reported in this thesis. We observe that the screw surfaces associated with the special RCCC linkage are analogous to the curves associated with the planar double-slider linkage. In addition, the loci of the handle of the three-position synthesis problem are categorized into three types, and two of them resemble the shape of a hyperboloid.
|
|---|
