Concept and Electro-elastic Modeling of Shear Actuated Fiber Composite using Micro-mechanics Approach

Abstract

A Shear Actuated Fiber Composite (SAFC) concept is developed that may find application in structural actuation and health monitoring tasks. The fabrication aspects of SAFC are briefly discussed. A uniform field model is employed to study electro-elastic behavior of the SAFC. The composite actuator is modeled as a general laminate having seven layers, and the effective properties are evaluated further using shear deformation lamination theory. The geometric parameters such as fiber volume fraction, fiber thickness, and fiber orientation are considered, and their influence on the characteristics of SAFC is analyzed. It is observed that a higher fiber thickness may provide better shear actuation capability for the SAFC actuator; but conformability requirements bring a constraint on fiber thickness that needs to be optimized. A fiber volume content of 85—95% appears to provide a design envelope for the SAFC actuator. SAFC has shown a promising feature of simultaneously coupling both transverse shear strains, if the poled PZT fibers are oriented directionally. Therefore, SAFC can be used as a torsional actuator for developing electro-elastically tailored smart laminated or sandwich structures. It is also expected that the SAFC actuator may provide a better solution for active aeroelastic control applications, where torsion mode is critical.