Parametric Design of a Spherical Eight-Bar Linkage Based on a Spherical Parallel Manipulator

This paper presents a procedure that determines the dimensions of two constraining links to be added to a three degree-of freedom spherical parallel manipulator so that it becomes a one degree- of-freedom spherical (8, 10) eight-bar linkage that guides its endeffector through five task poses. The dimensions of the spherical parallel manipulator are unconstrained, which provides the freedom to specify arbitrary base attachment points as well as the opportunity to shape the overall movement of the linkage. Inverse kinematics analysis of the spherical parallel manipulator provides a set of relative poses between all of the links, which are used to formulate the synthesis equations for spherical RR chains connecting any two of these links. The analysis of the resulting spherical eight-bar linkage verifies the movement of the system.

[1]  Zhen Huang,et al.  The Establishment of the Canonical Perimeter Topological Graph of Kinematic Chains and Isomorphism Identification , 2007 .

[2]  C. H. Chiang,et al.  Kinematics of Spherical Mechanisms , 1988 .

[3]  Joseph Duffy,et al.  A forward and reverse displacement analysis of an in-parallel spherical manipulator , 1994 .

[4]  Jorge Angeles,et al.  The Design of a Chain of Spherical Stephenson Mechanisms for a Gearless Robotic Pitch-Roll Wrist , 2006 .

[5]  L Burmester,et al.  Lehrbuch der Kinematik , 1888 .

[6]  J. McCarthy.  Planar and Spatial Rigid Motion as Special Cases of Spherical and 3-Spherical Motion , 1983 .

[7]  C. Gosselin,et al.  Singularity Loci of a Special Class of Spherical 3-DOF Parallel Mechanisms With Prismatic Actuators , 2004 .

[8]  Jorge Angeles,et al.  On the workspace determination of spherical serial and platform mechanisms , 1999 .

[9]  C. H. Suh,et al.  Kinematics and mechanisms design , 1978 .

[10]  C. Gosselin,et al.  Type Synthesis of 3-DOF Spherical Parallel Manipulators Based on Screw Theory , 2004 .

[11]  Pierre M. Larochelle,et al.  Computer-aided manufacturing of spherical mechanisms , 2007 .

[12]  J. Michael McCarthy,et al.  Introduction to theoretical kinematics , 1990 .

[13]  Hong-Sen Yan,et al.  Identifying and Counting the Number of Mechanisms From Kinematic Chains Subject to Design Constraints , 2006 .

[14]  McCarthy,et al.  Geometric Design of Linkages , 2000 .

[15]  Tarcisio A. Hess-Coelho.  A Redundant Parallel Spherical Mechanism for Robotic Wrist Applications , 2007 .

[16]  Bernard Roth,et al.  Design Equations for the Finitely and Infinitesimally Separated Position Synthesis of Binary Links and Combined Link Chains , 1969 .

[17]  José M. Rico,et al.  A family of spherical parallel manipulators with two legs , 2008 .

[18]  Rasim Alizade,et al.  Analytical synthesis of function generating spherical four-bar mechanism for the five precision points , 2005 .

[19]  Charles W. Wampler.  Displacement Analysis of Spherical Mechanisms Having Three or Fewer Loops , 2004 .