For smart materials that are useful in wide variety of applications such as microelectromechanical systems (MEMS), machine components, and artificial muscle, the nonlinear phenomena of hysteresis and creep are essential consideration. We investigated movement of an electroactive fiber composed of single-wall carbon nanotubes (SWNTs) and polyaniline (PANi)  and developed an integrated model that can be used for simulating and predicting the hysteresis (fig. 1) and the creep (fig. 2) during actuation. The Preisach operator , one of the most popular phenomenological models of hysteresis, was used in the modeling of hysteresis observed in the actuator. An inverse hysteresis model, which compensates the effects of hysteresis, was also presented and tested. And the creep effect, which is the drift of displacement for a constant electric potential, is depicted by the system identification technique . Understanding the behaviors of the creep effect is especially important in open-loop control of the actuator. In this paper, we showed mathematical description for the model as well as extraction of parameters. The model proposes an effective way to precisely controlling the fiber actuator in potential applications.
Journal: TechConnect Briefs
Volume: 3, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 3
Published: May 20, 2007
Pages: 185 - 188
Industry sector: Sensors, MEMS, Electronics
Topic: Sensors - Chemical, Physical & Bio