Funded Projects

Smart materials and structures are relevant to multifunctional structures, sensing, robotics and energy. Instead of using embedded or attached devices, this project will achieve the smartness by exploiting the inherent dielectric behavior of structural materials without embedded or attached devices (such as sensors and batteries). This approach is advantageous in its low cost, high durability, large functional volume and not causing any material property loss. The functions will be sensing (i.e., structural self-sensing) and energy generation (i.e., structural self-powering). The sensing pertains to the detection of the stress/strain and damage, as needed for vibration control and structural health monitoring. The powering function is achieved by the short-circuited discharge of the electret inherent in the structural material without the need for poling. After the discharge, open-circuited self-charge occurs, because the charged state is thermodynamically stable. The sensing method will involve measuring the capacitance and its tomography. The structural materials will be selected mainly from metals (e.g., steel) and carbon fiber composites, which are electrical conductors, but their dielectric and electret behavior has been only recently discovered by Chung. The composites are important for lightweight structures, e.g., airframe and satellites. Steel is important for construction, automobile, pipelines, etc. The three team members provide complementary expertise. Chung is the international leader in this field, having established the abovementioned abilities and opened the emerging field of conductive dielectrics. Bird is an expert in the electrical behavior of materials and will address the new physics behind conductive dielectrics and electrets. Bayandor is an expert in structures and damage assessment and will extend the work from the material level to the structure level, as needed for technology implementation.