Hellmuth Stachel
Vienna University of Technology, Wien
The spherical image of Bricard’s flexible octahedron of type 3 has first been studied 1912 by Bennett. It contains eight links and twelve revolute joints and collapses in aligned poses. During the flexion of this overconstrained spherical linkage eight points — one on each link — remain aligned. This is the basis for a symmetric placement of the self-motion and for extensions of the linkage. Moreover, it has consequences for the dualized version of Bennett’s 8-bar which is the composition of eight Bennett isograms.