Determine whether multiple contracting rods improve three-dimensional stiffness

Determine whether contracting multiple rods can improve the three-dimensional stiffness of the rod-driven continuum mechanism and mitigate the stiffness anisotropy observed in the planar mechanism.

Background

The demonstrated mechanism uses two rods and is limited to planar bending, with force locking producing anisotropic stiffness. The authors note that additional transmission elements could contract a larger section of the backbone, potentially enabling three-dimensional curvature and changing the stiffness distribution. Whether multiple contracting rods provide the anticipated stiffness improvement and anisotropy reduction remains unresolved.