Nonlinear Vibration of a One-Degree of Freedom Shape Memory Alloy Oscillator: A Numerical-experimental Investigation

Pseudoelastic Shape memory alloys (SMAs) are very attractive for passive vibration control due to their ability to sustain and retrieve large amounts of strain, dissipate high levels of energy and provide a restoring force to the system. They can be effectively used to attenuate vibrations of a primary system by introducing variable stiffness, and providing additional energy dissipation due to hysteresis. Motivated by these properties, this paper presents a dynamical investigation of a passive damping device, where the main elements are pseudoelastic SMA wires. The device, a mass connected to a frame by two SMA wires, was subjected to a series of continuous sinusoidal acceleration functions in the form of a sine sweep. Frequency responses and transmissibility of the device were analyzed for the case where the SMA wires were pre-strained at 4.0% of its original length. The temperatures of the wires throughout the dynamic tests were also recorded. In addition, numerical simulations of a single-degree of freedom SMA oscillator were conducted to corroborate experimental results. A thermodynamical constitutive model for SMAs was used to simulate constitutive pseudoelastic response of the SMA elements.