Validation of Resonant Frequency Model for Polypyrrole Trilayer Actuators

Conducting polymers are new materials that can be used as low-voltage actuators and active flexure joints, scaling down to the microscale; however, many devices based on these actuators are limited because they can only operate when submerged in an electrolyte. Conducting polymer trilayer actuators are laminated structures with a wide range of potential applications as they are capable of operating both in air and liquid environments, but their dynamic behavior is not yet fully understood. With the view to developing a comprehensive dynamic model of trilayer actuators, this paper presents the experimentally obtained frequency response of the actuator displacement, as measured using a laser displacement sensor. A model of the resonant frequency is also presented and then comprehensively validated using actuators of various geometry and loading. This model can be used to: 1) estimate properties of the trilayer actuator from experimental measurements; 2) quantify and optimize an actuator's dynamic behavior as a function of geometry; and 3) facilitate the use of these actuators as a component in practical applications, such as force and motion control systems.