Fluidic Flexible Matrix Composites for Autonomous Structural Tailoring

In previous research, a high-mechanical- advantage actuator system inspired by the fibrillar networks in plant cell walls was developed. One of the basic elements in the actuator system is a composite tube consisting of a flexible matrix and multiple layers of oriented, high-performance fibers such as carbon. By tailoring the properties of the fibers and matrix of the flexible matrix composite (FMC) tube, one can create a material that is flexible in certain directions, yet compliant in others. For example, the ratio of Young's moduli in the directions parallel and transverse to the fibers can range from 102 to 104. Strands of such FMC material can be wound into a tube at selected angles relative to the winding axis (a process called filament winding) such that the tube can contract or elongate axially via internal pressurization. It was previously shown that large strain and large force can be achieved with individual, pressurized FMC tubes, and that parallel arrays of tubular elements can be integrated to form 2D adaptive structures (e.g., skins and plates with multiple tubes).