Investigation and evaluation of effect of dehydration on vibration characteristics of silver-electroded ionic polymer–metal composite actuator

Abstract

Theoretical and experimental investigation of dehydration loss of ionic polymer–metal composite actuator is important to evaluate the stability, accuracy, and effectiveness of actuation. An ionic polymer–metal composite actuator of silver electrode has been analyzed to demonstrate the effect of dehydration on vibration characteristics during actuation. Experiment is conducted in cantilever configuration under direct current potential, and the bending and vibration characteristics are measured by Laser Vibrometer. As dehydration occurs during the actuation process, these experimental data are used to establish empirical model for loss-factor in terms of input voltage and time using Cobb–Douglas production method. A correlation is also developed for tip deflection with applied voltage. For theoretical investigation, multimode approximation has been taken into consideration and extended Hamilton’s principle is applied for developing the governing equation of motion of the actuator. Few modes are taken into consideration, and the equations are solved numerically to obtain the transient and steady-state responses of the actuator. Theoretical steady-state results are compared and validated with the experimental results. Both theoretical and experimental results show the gradual reduction of tip displacement due to dehydration.