A bio-inspired device to detect equilibrium variations using IPMCs and ferrofluids

This work describes a device designed and built to detect the inclination of a body, based on two emerging smart materials: ionic polymer–metal composites (IPMCs) and ferrofluids. The system is bio-inspired and simulates the behavior of the vestibular labyrinth, a biological component of living beings, situated in the inner ear and devoted to perception of the angular acceleration the head is subjected to. In the same way the proposed system is able to reveal its inclination by detecting the position of a ferrofluid mass inside a circular tube. The detection is performed by using the sensing properties of IPMCs, cut into opportunely sized strips, acting as ciliate cells in the tube. The system, details of which are given in the text, is totally new and combines two innovative technologies, IPMCs and ferrofluids, that allow good performance to be obtained at a low cost. The experimental setup is presented and several results are shown and discussed.