Integrated static and dynamic modeling of an ionic polymer–metal composite actuator

Abstract

Ionic polymer-metal composites have been widely used as actuators for robotic systems. In this article, we investigate and verify the characteristics of ionic polymer-metal composite actuators experimentally and theoretically. Two analytical models are utilized to analyze the performance of ionic polymer-metal composites: a linear irreversible electrodynamical model and a dynamic model. We find that the first model accurately predicts the static characteristics of the ionic polymer-metal composite according to the Onsager equations, while the second model is able to reveal the back relaxation characteristics of the ionic polymer-metal composite. We combine the static and dynamic models of the ionic polymer-metal composite and derive the transfer function for the ionic polymer-metal composite's mechanical response to an electrical signal. A driving signal with a smooth slope and a low frequency is beneficial for the power efficiency.

MXene artificial muscles based on ionically cross-linked Ti 3 C 2 T x electrode for kinetic soft robotics

“…A large amount of PP not only reduced capacitance but also hindered the charge path, as well as reducing the ion adsorption via low porosity and surface roughness, causing slow response time. Besides this, back-relaxation behavior was noticed to a minimal extent only in the neat PP and T1PP4 AWIS actuators during the DC test under 0.5 V for 1100 s. The back-relaxation was expected to be due to the diffusion effect of water molecules (absorbed from the open air) in the outer layer because of the hygroscopic nature of PP (45). However, in the case of T1PP2, there might not be free PP molecules due to the availability of an appropriate amount of MXene to make ionic bonds.…”

Electrochemical and Electromechanical Study of Carbon-Electrode-Based Ionic Soft Actuators

“…Through this chemical process, metal nanoparticles form a dense layer at the top surface of the membrane and they also penetrate into the subsurface of the membrane and form a dendritic metallic structure at these regions. This process may be repeated many times to improve the electrode surface structure and surface conductivity. , In general, the actuation mechanism of IPMCs is described considering the strong impact of hydraulic and electrostatic effects. − Therefore, the hydration level, ionic content, the surface conductivity, and the flexibility of the electrode layers of IPMCs play key roles in the intensity of their response …”

Experimental study on strain distribution of ionic polymer–metal composite actuator using digital image correlation

“…The deformation of the IPMC actuator under DC excitation voltage was unstable due to back relaxation, which occurred after reaching the maximum deflection. This phenomenon may be prevented by applying a current excitation signal [28,29].…”