Insight into single-helix intelligent shape memory polymer cables: modeling and optimization under finite sliding contact

Abstract

Proposing shape memory polymer (SMP) materials for lifting and rigging equipment can foster unparalleled advancements and several potential applications in various industries. This pioneering study focuses on the thermomechanical properties of SMP wire ropes and their components during programming steps for small- and finite-sliding contact deformation. Employing existing experimental data and numerical results, we validate our finite element analysis (FEA) for both geometric modeling and non-linear material behavior. Owing to intricate geometry, as well as excessive wire interactions, the former is studied by simulating a 1×37 steel wire rope, and the thermomechanical property of an SMP rectangular bar under a uniaxial test is modeled to verify both constrained and unconstrained recovery behavior. After rigorous validation, two configurations of 1×7 and 1×27 SMP cables are modeled based on the thermo-visco-hyperelastic constitutive framework. Exerting an axial load on these wire ropes, the response of force and shape recovery, as well as the normal and shear stress distributions, are measured under constrained and unconstrained conditions. For a deeper physical understanding, we also conduct parametric studies to elucidate the influences of temperature rate, frictional coefficient, and multiple-shape programming on the performance of SMP cables. Furthermore, to propose a comprehensive discussion on these newly developed instruments, the specific energy of a 1×6 SMP cable is maximized using the design of experiments based on optimizing two cable factors of diameter and helix angle. This study tries to cast light on the remarkable features and possible potential of SMP cables in applications under different thermomechanical loadings.