本研究將HEXA並聯式機械手臂修改為6RUS並聯式機械手臂，使得正向位置分析的閉合解可以求出。本論文並從事此6RUS機構之工作空間、正向奇異位置以及剛性分析。在正向位置分析過程中，首先將6RUS機構簡化為等效3RS結構，利用活動平台之球窩接頭間的距離為已知長度，推導出三個多項式方程式，再使用席維斯透析消去法(Sylvester dialytic elimination method)求得正向位置之解。本論文利用逆向位置分析技巧求出此機構的定向工作空間與方向工作空間。 本研究使用螺旋理論，求出螺旋Jacobian矩陣，同時亦求出HEXA並聯式機械手臂螺旋Jacobian矩陣，利用此矩陣可得到6RUS與HEXA並聯式機械手臂的正向奇異位置與中心結構時的剛性。 In this dissertation, the structure of the 6 degree-of-freedom parallel manipulator HEXA is modified to take a 6RUS form so that closed-form solutions for direct kinematic analysis can be found. In addition, workspace analysis, direct singular position analysis, and stiffness analysis on this 6RUS manipulator are also performed. In direct kinematic analysis, the manipulator is first transformed into an equivalent 3RS structure, and then three polynomial equations are obtained by using the property of constant length between three spherical joints on the moving platform. Sylvester dialytic elimination method is used to obtain direct kinematic solutions. Constant orientation workspace and orientation workspace are found by performing inverse position analysis. Jacobian matrices of HEXA and the 6RUS manipulator are obtained by using screw theory. Certain direct singular positions of the two manipulators are found from these matrices. Also determined from the Jacobian matrices is the stiffness of central configuration of the two manipulators.
