“Artificial muscle”: Electromechanical actuators using polyaniline films

Polyaniline films are found to expand and contract by electrochemical oxidation and reduction, respectively. Two polyaniline films are used as cathode and anode muscles. In this system, the proton transfer between the films are essential chemical reaction. Two types of actuators, viz., “Backbone-type” and “Shell-type” actuators have been fabricated. The “Backbone-type” actuator responded to the frequency of more than 44Hz. The “Shell-type” actuator can be operated in free space.