Training, Control and Application of SMA-Based Actuators with Two-Way Shape Memory Effect

Abstract

Shape memory alloys (SMAs) are widely used in aerospace, automobile, and other fields because of their excellent properties, such as large driving force and large deformation. A training method with a bidirectional memory effect is proposed for SMA actuators. The trained SMA units can be heated and cooled to change their shape (shorten and extend). The trained SMA is used as an actuator to drive the deformation of a structure. Due to the obvious hysteresis characteristics of SMA, a temperature-displacement hysteresis model based on the Preisach model is proposed in order to reduce the influence of hysteresis in the process of structural deformation. The F function method (FFM) is used for Preisach numerical implementation, and a PID control method is used for the precise control of structural deformation. Compared with the PID control method without hysteresis model, this method is superior to the PID control method in response speed and control accuracy. The maximum relative error of three target points in the experiment is 5.45%, which is better than the PID control method without this model. The hysteresis model can be applied to the displacement control of a SMA-based actuator.

Design, Modeling, and Experimental Validation of an Active Microcatheter Driven by Shape Memory Effects

“…In this study, a combination of two different materials is proposed for the design of active microcatheters. Shape memory alloys are widely used in different situations due to their remarkable shape memory effects, as well as their biocompatibility [19][20][21]. Once being heated beyond its austenite finish temperature, proper annealed SMA would regain its memorized shape at a much higher annealing temperature, eliminating its macroscopic deformation occurring in the martensitic phase.…”

Design and Control of a Shape Memory Alloy-Based Idle Air Control Actuator for a Mid-Size Passenger Vehicle Application

“…Plate-based shape memory alloys are used in aerospace actuators for the vibration and stiffness control of flexible structures [21]. In the automotive industry, they are applied in adaptive shock control actuators [22,23]. The actuators with improved stroke and fast actuation responses use spring-based shape memory alloys [13,24].…”