A Novel S-C-U Dual Four-Bar Linkage

Abstract

This paper presents the kinematic architecture, analysis, and simulation of the S-C-U Dual Four-Bar Linkage (Larochelle and Du, Dual four-bar linkage mechanism, 2015, [4]). The S-C-U Dual Four-Bar Linkage, or SCUD Linkage, is a biologically inspired design for articulating the leg in a mechanical walking machine. The SCUD Linkage consists of dual planar four-bar mechanisms used to support and generate the desired motion of a rod in three-dimensional space. The rod is supported by two joints; each of these binary joints connecting the rod to a coupler point on a planar four-bar mechanism. At one end of the rod a universal joint connects it to a coupler point. At the rod’s midpoint, a combination of a cylindrical joint and a spherical joint are used to connect it to the other supporting coupler point. The result is a two degree of freedom closed kinematic chain with two parallel sub chains. The end-effector or workpiece of the SCUD Linkage is affixed to the free end of the rod. Here, the concept of the SCUD Linkage as well as its kinematic analysis and simulation are presented. The analysis of an example SCUD Linkage is included.