Development and modelling of textile based actuatorsThursday (24.09.2020) 09:15 - 09:30 Z: Special Symposia II Part of:
Due to their ability to change their physical or chemical properties (e.g. shape, volume, stiffness, color or internal temperature) on demand, smart materials have generated increasing interest within the industry over the past ten years. Compared to a traditional rigid design, smart materials offer considerable advantages, such as faster systems, more responsive and reliable processes or improved operating characteristics. The Research Training Group “Interactive Fiber-Rubber Composites” (I-FRC) is focused on the development of a new class of composite materials, which are able to modify their shape when electrical, magnetical or thermal stimulation is applied, thus eliminating the need of additional components (e.g. engines, sophisticated kinematic steering etc.). This presentation focusses on two main subjects:
In the first approach, textile actuators based on shape memory alloys (SMA) are integrated into fiber-reinforced elastomeric composites. By connecting the SMA-based actuators to an electrical voltage, they rapidly heat up above their specific transition temperature, leading to a significant material deformation, a process that subsequently induces a deflection of the composite. Thus, it is possible to actively achieve and control large deformations of the structures up to 180° of bending angle. In order to describe the inherent mechanisms and to minimize the experimental effort needed for creating optimized topologies, FEM-based modeling of the structural components and their properties and effects is utilized.
The second approach encompasses the development of electrically conductive, elastic yarns. Electrically conductive fibers, like copper wires, carbon rovings or metallized filament yarns, are required for several fields of application in modern textile technology, like smart textiles and composites with textile-based sensor and actuator systems. The commonly used materials offer very good electrical conductivity but possess low mechanical elongation capabilities. Therefore, for applications that require a high flexibility of the textile structure, as in the case of wearable smart textiles and I-FRC, the development of electrically conductive, elastic yarns is highly beneficial. Therefore highly stretchable TPU was compounded with electrically conductive carbon nanotubes (CNT) and melt spun.