Neural Network Approach to Modelling the Behaviour of Ionic Polymer-Metal Composites in Dry Environments

Abstract

Ionic polymer-metal composites (IPMCs) are especially interesting electroactive polymers because they show large a deformation in the presence of a very low driving voltage (around 1 - 2 V) and several applications have recently been proposed. Normally a humid environment is required for the best operation, although some IPMCs can operate in a dry environment, after proper encapsulation or if a solid electrolyte is used in the manufacturing process. However, such solutions usually lead to increasing mechanical stiffness and to a reduction of actuation capabilities. In this study we focus on the behaviour of non-encapsulated IPMCs as actuators in dry environments, in order to obtain relevant information for design tasks linked to the development of active devices based on this kind of smart material. The non-linear response obtained in the characterisation tests is especially well-suited to modelling these actuators with the help of artificial neural networks (ANNs). Once trained with the help of characterisation data, such neural networks prove to be a precise simulation tool for describing IPMC response in dry environments

Adaptive observer-based control for an IPMC actuator under varying humidity conditions

“…In [26], a mixture theory framework for mechanical modeling of IPMC was presented. The model proposed in [27] is an attempt to use a black-box-based modeling approach to characterize the influence of environmental humidity on IPMC behavior. In [28], a multi-physics model of IPMC actuators analyzes the relationship between the environmental relative humidity and the device transduction capabilities.…”

A multiphysics model of IPMC actuators dependence on relative humidity

“…Nevertheless, black-box models have been more recently proposed in the literature. More specifically in [6] the time varying nature of IPMC actuator performances, using water as the solvent, when working in dry environment was modeled by using artificial neural networks. The model proposed in [6] is actually an attempt to use a black-box modeling approach to model the influence of the environmental humidity on IPMC behavior.…”

“…The objective of this paper is the introduction of a new IPMC actuator model that takes into account the effect of humidity [6] [14] [15] [16].…”

“…More specifically in [6][15] [16] the modeling of the dependence of IPMC behavior on environmental humidity is obtained by using a black-box approach, while in [14] some of the authors proposed the modeling and characterization of IPMC actuators with respect to humidity, obtained by using a grey-box approach.…”