Adaptive inverse modeling of a shape memory alloy wire actuator and tracking control with the model

摘要

It is well known that the Preisach model is useful to approximate the effect ofhysteresis behavior in smart materials, such as piezoactuators and Shape MemoryAlloy(SMA) wire actuators. For tracking control, many researchers estimate a Preisachmodel and then compute its inverse model for hysteresis compensation. However, theinverse of its hysteresis behavior also shows hysteresis behavior. From this idea, theinverse model with Kransnoselskii-Pokrovskii(KP) model, a developed version ofPreisach model, can be used directly for SMA position control and avoid the inverseoperation. Also, we propose another method for the tracking control by approximatingthe inverse model using an orthogonal polynomial network. To estimate and update theweight parameters in both inverse models, a gradient-based learning algorithm is used.Finally, for the SMA position control, PID controller, adaptive controllers with KPmodel and adaptive nonlinear inverse model controller are compared experimentally.