【摘要】 提出一种新型2-TPR/2-TPS空间4自由度并联机构。机构的运动平台通过两个相邻的TPR分支运动链和两个相邻的TPS分支运动链与固定平台相联接。每个TPR分支由一个胡克铰T、一个移动副P和一个转动副R组成,一端通过胡克铰T与固定平台相联,另一端通过转动副R与运动平台相联;每个TPS分支由一个胡克铰T、一个移动副P和一个球面副S组成,一端通过胡克铰T与固定平台相联,另一端通过球面副S与运动平台相联。运用约束螺旋理论,对机构的运动性质和奇异位形进行分析。机构运动平台具有沿两个TPR分支所在平面的二维移动自由度,和以两个TPR分支胡克铰二级转动副轴线所在平面内的任何直线作为转轴的二维转动自由度。选取4个分支运动链的移动副作为驱动副,发现了机构可能出现的四种奇异位形。更多还原

【Abstract】 A novel 2-TPR/2-TPS spatial 4-DOF parallel mechanism is proposed.The proposed mechanism is composed of a moving platform connected to a fixed platform by means of four actuated limbs.The two of the four limbs are adjacent TPS serial manipulators and the other two are adjacent TPS serial manipulators.Each TPR limb consists of a Hoke joint T connecting to the fixed platform,a prismatic pair P,and a revolute pair R connecting to the moving platform.Each TPS limb consists ofa Hoke joint T connecting to the fixed platform,a prismatic pair P,and a spherical pair S connecting to the moving platform.Moving character and singularity of this mechanism are analyzed by using the screw theory.The moving platform of this mechanism has 2 translational DOFs,and they are translational movings along the plane which passes through the two TPR limbs.The moving platform of this mechanism also has 2 rotational DOFs,and they are rotational movings that are rotated the lines in the plane which passes through the second rotational axes of each Hoke joint of the two TPR limbs.The prismatic pair of each limb can be actuated.Four possible types of singular configuration of this mechanism are achieved.更多还原