Detailed Info (Full-length paper: N. Ma, G. Song, and H-J Lee, "Position control of shape memory alloy actuators with internal electrical resistance feedback using neural networks." Smart Materials and Structures, vol. 12, pp. 223-231, 2000.) Position control of shape memory alloy actuators with internal electrical resistance feedback using neural networks
Abstract
The development of a position control system for a shape memory alloy (SMA) wire actuator using an electrical resistance feedback is presented in this paper. A novel control scheme is implemented to eliminate the need for a position sensor to achieve stable and accurate positioning by utilizing the actuator’s electrical resistance feedback. Experiments are conducted to investigate the relationship between electrical resistance and displacement using a SMA wire test setup. Due to the highly nonlinear behavior of the SMA actuator, a neural network is employed to model the relationship and to predict the position of the actuator using only the electrical resistance. Feedback control of the SMA is achieved by using a Proportional-Derivative (PD) controller. Experimental results demonstrate that the proposed position control system achieves good control performance without using a position sensor.