Strain transfer models for macrofiber-composite strain actuators

This article develops one-dimensional and two-dimensional strain transfer models for macrofiber composite (MFC) actuators under quasi-static excitation. The adhesive layer (epoxy) between the actuator and the structure is considered in the Bernoulli-Euler formulation, and the results for various models are compared with the uniform strain model which includes the shear lag effect due to the adhesive layer. The reduction in actuation as a result of strain distribution inside the MFC actuator is considered to improve the prediction ability of the existing models based on the Bernoulli-Euler formulation. Finite element simulation is also carried out to study the strain transfer for both quasi-static and near natural frequency excitations. The effects of the thickness and modulus of elasticity of the adhesive layer on strain transfer are discussed. Finally, an experimental test is conducted to evaluate the accuracy and limitations of the developed models. Results show that the models are in good agreement with the experimental test.