Nonlinear Dynamics of a SMA Large-Scale Space Structure

Large-scale structures are of special interest of aerospace applications, especially the ones involving smart materials. This paper deals with an archetypal system with two degrees of freedom that resembles the use of SMA elements as vibration isolation systems on a sparse aperture satellite array. The system has SMA elements in two perpendicular directions connected to a mass. Each SMA element is connected to a base structure. Imperfections are represented by establishing a comparison between two different systems: ideal and perturbed configuration system. The perturbed configuration is characterized by a situation where all SMA elements are in a stress-free state. The thermomechanical behavior of SMA elements is described by a constitutive model with internal constrains. Numerical tests of this system are of concern showing its general dynamical behavior. Periodic and chaotic motions are investigated showing the complex behaviors of this kind of system. The effect of imperfection in system dynamics is also discussed.