On Singularity and Instability in a Planar Parallel Continuum Mechanism

Parallel Continuum Mechanisms are closed-loop mechanical systems formed by flexible rods connected to a rigid end-effector and actuated from the base attachments of such rods. It was shown in previous works that they have analogous kinematic features to rigid-link parallel mechanisms. Position analysis is a force equilibrium problem with a multiplicity of solutions. These correspond to distinct aspects of workspaces, delimited by singularity curves. Equilibrium poses need further analysis to verify their stability, i.e. if the stationary solution is a local minima of the potential energy of the device. This conference paper investigates singularity and instability issues to understand the behavior of the mechanism in such poses.