Towards Hyper-Redundant and Super-Configurable Articulated Structures

In this paper, we describe preliminary analysis for a method of constructing homogeneous actuated electromechanical composite structures from many smaller electromechanical “active cells”. The preliminary cell design consists of a contractile shape memory alloy (SMA) elements (Nitinol) connecting two electrically conductive terminals. The composite structure is actuated by applying a gross electrical potential across the entire structure. This causes connected cells to activate through resistive heating. The material properties of the ensemble structure can be varied by changing the properties of the binding material, enabling a wide range of stiffness and damping properties. A structure made from these cells can be easily fabricated in a nearly arbitrary shape — simply by producing an appropriate mold — and would be highly redundant and robust to localized cell failures. The primary focus of this paper is to perform a static analysis of the connectivity of arrays of active cells and the associated power dissipation in the individual cells.