Carbon fiber is a light, strong, and stiff material, allowing it to serve as a structural material in applications that require a high strength and stiffness with as little weight as possible, such as the wings of a bird or a plane. Due to its piezoresistive properties, some details about the state of the fibers (stress, strain, fracture) can also be extracted through electrical measurements, allowing the carbon fibers to act as sensors. By leveraging CFC (continuous fiber coextrusion) 3D printing, the creation of complex, strong, lightweight, self-sensing structures is made possible.
This thesis characterizes the resistance response of carbon fiber based strain gauges by means of a three point bending test. Classical beam theory is used to model the beams, and an electrical model is used to predict the response of the strain gauges. The carbon fiber strain gauges show a high sensitivity and low noise, making this topic a promising area for future research.