Ionomeric polymers are a promising class of intelligent material which exhibit electromechanical coupling similar to that of piezoelectric bimorphs. Ionomeric polymers are much more compliant than piezoelectric ceramics or polymers and have been shown to produce actuation strain on the order of 5% at operating voltages between 1 V and 5 V. This performance indicates the potential for self-actuating devices manufactured from ionomeric polymers, such as deformable mirrors or low pressure pump diaphragms. This paper presents a variational approach to the dynamic modeling of ionic polymer plates in rectangular coordinates. A linear matrix equation, which relates displacement and charge to applied forces and voltage, is developed to determine the response of the structure to applied forces and applied potentials. The modeling method is based on the incorporation of empirically determined material properties, which have been shown to be highly frequency dependent. The matrices are calculated at discrete frequencies and solved frequency-by-frequency
to determine the response of the ionomeric plate structures. A model of a thin rectangular plate is developed and validated experimentally. Simulated frequency response functions are compared to experimental results for several locations on the plate. The response of the plate at certain frequencies is computed and compared to experimentally-determined response shapes. The results
demonstrate the validity of the modeling approach in predicting the dynamic response of the ionomeric plate structure. These spatial solutions are also compared to experimentally determined response shapes.
Ionomeric polymers are a promising class of intelligent material which exhibit electromechanical coupling similar to that of piezoelectric bimorphs. Ionomeric polymers are much more compliant than piezoelectric ceramics or polymers and have been shown to produce actuation strain on the order of 2% at operating voltages between 1 V and 3 V. Their high compliance is also advantageous in low force sensing configurations because ionic polymers have a very little impact on the dynamics of the measured system. This paper presents a variational approach to the dynamic modeling of ionic polymer actuators and sensors. The approach requires a priori knowledge of three empirically determined material properties: elastic modulus, dielectric permittivity, and effective strain coefficient. Previous work by Newbury and Leo has demonstrated that these three parameters are strongly frequency dependent in the range between less than 1 Hz to frequencies greater than 1 kHz. A model of a cantilever beam incorporating this frequency dependence has been developed. The variational method produces a second-order matrix representation of the structure. The frequency dependence of the material parameters is incorporated using a complex-property approach similar to the techniques for modeling viscoelastic materials. A transducer was manufactured and the method of material characterization is outlined. Additional experiments are performed on this transducer and both the material and structural model are validated. The modeling method is then used to simulate the performance of actuators and sensors in a cantilever configuration.