A linear actuator from a single ionic polymer-metal composite (IPMC) strip

We present a novel linear actuator made from a single Ionic Polymer-Metal Composite (IPMC) strip. In its simplest form the device activates into the shape of a double-clamped buckled beam. This structure was chosen following observation of the buckle failure modes of axially compressed beams. The practical realization of this device is made possible by the development of new manufacturing techniques also described. The benefit of this buckled beam structure is that bending moments in the two halves of the beam cancel each other out. As a result, only one bending actuator is needed to form a single linear actuator and there is no need for mechanical joining of separate actuators - a disadvantage of previous linear actuator designs. The non-rotating nature of the end fixing in the double-clamped buckled beam also means that joining multiple elements to increase displacement or force is trivial. We present initial experimental results of a single linear actuator and a balanced, pair-connected linear actuator.