Synthesis and Motion Analysis of a Single-Loop 8R-Chain

In this paper two well known single-loop overconstrained 6 R-mechanisms are combined to synthesize a single-loop 8 R-mechanism. For the synthesized single-loop mechanism the arbitrary two degrees-of-freedom 8R motion modes are computed. As an example a 7 R sub-motion is shown as when one of the revolute joints is locked. Because of the construction of the new mechanism the motion of the initial six bars arise as one parametric sub-motions of the constructed one.