Theoretical analysis and design for a multilayered ionic polymer metal composite actuator

Abstract

Ionic polymer metal composites with a flexible large deformation have been used as biomimetic actuators and sensors in various fields. This work mainly focuses on the validation of the proposed theoretical prediction for various ionic polymer metal composite applications, such as a field needing a large resultant force, large tip deflection, or high response frequency. Such properties can be controlled by the number of layers and the thickness ratio of a multilayered ionic polymer metal composite actuator. Thus, we considered major design factors such as the number of layers and the thickness ratio in analysis of the proposed theoretical model and performed experiments to verify the static and dynamic electromechanical responses of multilayered (multimorph) ionic polymer metal composite structures acting as actuators. The relation between the polymer (Nafion) and electrode or substrate is represented by β. From this theoretical analysis, three properties were analyzed and predicted based on the Euler–Bernoulli beam theory, considering the dynamics of the ionic polymer metal composite, electrode, and bonding layers (substrate layers). The predicted results of a symmetric ionic polymer metal composite multimorph were compared with results of finite element analysis and experiments using ionic polymer metal composite multimorphs with one to five layers. Finally, this work examined how the number of layers and thickness affect the dynamic properties. This can contribute to predicting and optimally designing a multilayered ionic polymer metal composite actuator for satisfying a specific requirement.

Actuation and blocking force of stacked nanocarbon polymer actuators

“…As previously mentioned, several authors reported that multilayer of thin actuators was used for developing actuator showing both large displacement and force [12][13][14][15][16][17]. They also reported the multilayer actuator model.…”

“…Therefore, there are trade-off relations between the thickness of the actuator film (electrode and electrolyte) and bending displacement, speed, and force. In several studies, stacking several thin actuators has been used as a method of solving this issue of trade-off relations [12][13][14][15][16][17]. (Figure 1(b)) In this case, the most important issue is that the insulation layer between actuator electrodes prevents the contraction/elongation of each electrode layer, which decreases the motion of the stacked actuator.…”

Highly efficient structure design of bending stacking actuators based on IPMC with large output force

“…For single layer iEAPs, according to the electroactive performance, the energy density can be calculated ∼5 KJ m −3 , which has reach the same level of the biological muscles (8-40 KJ m −3 ) [31]; however, the thin membrane structure of iEAP actuators limits the further improvement of the output force. Current research on stacking structures primarily include serial stacking structure and parallel stacking structure, in which the driving actuators are directly attached together [32,33]. However, when directly sticking iEAP actuators together, the bending deformation coordination problem will occur that the stacking layer will generate a tangential force to restrain the bending deformation or output force performance of the structure and reduce the stacking efficiency.…”