Numerical study on dynamic characteristics of micromachined ionic polymer metal composite devices based on molecular-scale modeling

A molecular scale electro-chemo-mechanical model is newly presented to explain the dynamic characteristics of the developed micromachined ionic polymer metal composite (μIPMC) devices. Established from the Newton’s second law of motion, utilizing the Coulomb’s law, Stokes’ law, concentration gradient of particles to describe the associated forces, and accompanied by the application of mass conservation principle, the model is derived to elucidate the time-dependent charge transport of the moving cation concentration of μIPMC devices. A constitutive relation associating the concentration of moving cations with induced in-plane stress according to Coulomb’s law is also proposed. The numerical analysis results show good correlation with our previous experimental outcomes. More dynamic properties of the μIPMC transducer based on the derived model, including the concentration of moving cations, induced stress, generated moment and displacement under the influence of voltage amplitude, operating frequency, actuation time and driving waveform, are further discussed in this paper.