An actuator model of ICPF for robotic applications on the basis of physicochemical hypotheses

Abstract

The ICPF (Ionic Conducting Polymer gel Film) actuator is a new high polymer gel actuator by which revolutionary robotic mechanisms are expected. Actuator models for CAE are essential to the robotic design. However, present black/gray-box models of ICPF cannot express its nonlinear characteristics with enough accuracy, In this paper, a white-box actuator model is proposed on the basis of physicochemical hypotheses on the motion principle which are supported at present. In this model, travel of sodium ions and water molecules in the actuator membrane is modeled. Internal stress is generated by swell and contraction of the gel by water content change, electrostatic force of jixed sulfonic acid groups, and momentum conservation effect. Simulation results show higher accuracy on transient response and nonlinear characteristics in comparison with conventional models.

Study of the Influence of the Hydration Level on the Electromechanical Behavior of Nafion Based Ionomeric Polymer-metal Composites Actuators

“…Several electromechanical models have been proposed to explain the mechanisms responsible to the movement of the IPMC. These models are based on several assumptions, including solvent/ionic diffusion 1,10,11 , electrical interactions between ionic species [12][13][14] and the viscoelastic properties of the polymer phase 15 . [12][13][14] associated the bending movements to the electrical interactions resulted from the redistribution of the mobile cations without significant water molecules migration.…”

Finite Element Modeling of Electrochemical-Poroelastic Behaviors of Conducting Polymer Films

“…Moving ions in the electrolyte bath are subjected to the forces due to viscous resistance, diffusion and electricity, the balance of which leads to the following differential equation with respect to the total electric charge ) , ( t x Q (6) :…”

“…Assuming that the electrodes in the polymer film and the electrolyte are located respectively at 0 = x and d x = , the initial and boundary conditions are as follows (6) :…”

“…(1)-(3) based on Biot's poroelasticity theory (9) is extended to the formulation for the active, electrochemical-poroelastic behavior according to Onsager's law (10) , which is combined with the one-dimensional ionic transportation equation given by Tadokoro et al (6) to construct the system of governing equations. The governing equations are discretized by the finite element method.…”

Computational Modeling of Electrochemical-Poroelastic Bending Behaviors of Conducting Polymer (PPy) Membranes

“…The computational modeling combining the one-dimensional ionic transportation equation given by Tadokoro et al (9) and the formulation for the active electrochemical-poroelastic behavior of PPys given by Della Santa et al (10), (11) and the authors (12) is established for the PPy bending actuators acting in the electrolyte liquid and the electrolyte gel. The linear poroelastic model is extended to the poroelastic model considering the geometrical nonlinearity by the total Lagrangian approach in order to take account of the large deformation of PPy membranes.…”