Abstract:

We proposed a dynamic model identification and design of an H-Infinity (i.e. H∞) controller using a Lightweight Piezo-Composite Actuator (LIPCA). A second-order dynamic model was obtained by using input and output data, and applying an identification algorithm. The identified model coincides well with the real LIPCA. To reduce the resonating mode that is typical of piezoelectric actuators, a notch filter was used. A feedback controller using the H∞ control scheme was designed based on the identified dynamic model; thus, the LIPCA can be easily used as an actuator for biomemetic applications such as artificial muscles or macro/micro positioning in bioengineering. The control algorithm was implemented using a microprocessor, analog filters, and power amplifying drivers. Our simulation and experimental results demonstrate that the proposed control algorithm works well in real environment, providing robust performance and stability with uncertain disturbances.

Key words: piezoelectric actuator, model identification, H-infinity controller, biomimetic artificial muscle, LIPCA