<title>Design and modeling of a novel spring-loaded ionic polymeric gel actuator</title>

Abstract

A novel design for a helical spring-loaded ionic polymeric gel actuator is presented, specifically an encapsulated hermetically sealed, helical compression spring-loaded cylindrical linear actuator containing a counterionic solution or electrolyte such as water + acetone, a cylindrical helical compression spring and a collection of polymeric gel fibers. The proposed design is such that the helical spring not only acts as a compression spring between the two hermetically sealed circular end caps but contains snugly the polymeric gel fiber bundle and also acts as the cathode (anode) electrode while the two actuator caps act as the anode (cathode) electrodes. Electrical control of the expansion and the contraction of the linear actuator is possible. A mathematical model is presented for the dynamic response of contractile fiber bundles embedded in or around elastic springs that are either linear helical compression springs or hyperelastic springs such as rubber-like materials. The proposed model considers the electrically or pH-induced contraction of the fibers for the computer-controlled dynamic performance of the actuator.