Electroactive elastomeric actuators for biomedical and bioinspired systems

The family of ElectroActive Polymers for electromechanical transduction, better referred to as Electromechanically Active Polymers (EAPs), groups `smart´ materials that exhibit a mechanical response to an electrical stimulus, while offering, at the same time, light weight, mechanical compliance, compact size, simple structure, low power consumption, acoustically silent operation, and low cost. This paper deals with one of the most versatile and performing EAP technologies, known as dielectric elastomer actuators. The paper presents how combing dielectric elastomer actuation with fluid-based hydrostatic transmission is an effective means to conceive new devices that allow for biomedical and bioinspired systems impossible with other technologies. Three examples of applications under development in our lab are presented and discussed. The first is a wearable tactile display that provides users with tactile feedback during electronic navigation in virtual environments. The second deals with refreshable Braille displays as portable tactile readers for the blind people. The third example refers to electrically tunable optical lenses, inspired to the architecture of the crystalline lens and ciliary muscle of the human eye.