Electrostrictive actuators are a relatively new development in the field of smart material actuators. However, a major deficiency of electrostrictive actuators is their limitation of motion accuracy due to inherent non-linearity and hysteresis. This paper presents a new iterative learning control approach to improve the positioning/tracking accuracy of electrostrictive actuators. In this scheme, the iterative gain is not fixed but variable according to previous trial result and the nominal input/output relationship of the electrostrictive actuator. The convergence to the desired position/trajectory is theoretically proved. The effectiveness ofthis control scheme is experimentally demonstrated through actual positioning and tracking control ofa stacked electrostrictive actuator. The results show that using this variable gain iterative learning control scheme, not only can the stability of precision positioning be obviously improved, but also precise and non-delay tracking can be achieved.

Date Published: 21 March 2001
PDF: 7 pages
Proc. SPIE 4235, Smart Structures and Devices, (21 March 2001); doi: 10.1117/12.420873

Published in SPIE Proceedings Vol. 4235:
Smart Structures and Devices
Dinesh K. Sood; Ronald Albert Lawes; Vasundara V. Varadan, Editor(s)