Sensor-integrated high-volume direct pellet continuous fiber-reinforced supportless robotic 3D printing

纤维增强塑料(FRP)由聚合物和增强相组成，如玻璃和碳纤维。虽然FRPS通常用于高成本应用，如航空航天和国防部门，但材料成本的显著降低使FRPS对汽车和建筑行业也具有吸引力。玻璃钢具有优异的硬度和强度重量比，以及高耐腐蚀性，使其成为金属合金的高性能替代品。然而，玻璃钢零件的制造，特别是对于像管和板这样的几何形状，仍然是一个复杂的过程，包括制造纤维预制件，如织物，然后将聚合物添加到预制件中，并使用专门的工具形成和固化零件。这个多步骤的过程是劳动密集型的、耗时的，并且由于需要人工干预而容易出现质量变化。FRPS的3D打印是一个新兴的领域，主要集中在热塑性聚合物上，主要是短纤维，导致复合材料部件的硬度和拉伸强度有限，因此几乎没有机会创造出性能更好的工业部件。本提案旨在通过研究和开发一种机器人直接挤出3D打印系统来克服这些限制，该系统能够3D打印连续纤维增强塑料，以生产具有工业相关性和性能的部件。该研究还将开发传感器和制造数据分析系统，通过识别和开发(I)检测和减轻部件变形的传感器，(2)监控部件中连续纤维形态的系统，以及(Iii)主动控制沉积层的高度，来确保印刷部件的在线质量控制。该项目还将创建特殊的计算机辅助制造策略，例如，为3D打印部件提供二维编织能力，并实现真正的五轴运动，以实现无支架部件打印。

Fiber-reinforced plastics (FRPs) are comprised of a polymer and a reinforcement phase such as glass and carbon fibers. While FRPs have commonly been used in high-cost applications such as in the aerospace and defense sectors, significant reductions in material costs have made FRPs attractive also to the automotive and construction industries. FRPs offer excellent stiffness- and strength-to-weight ratios, as well as high corrosion resistance, making them a high-performance alternative to metal alloys. However, the fabrication of FRP parts, especially for geometries that are not trivial like tubes and plates, remains a complex process comprising the manufacture of fiber preforms such as fabrics, followed by adding the polymer to the preform and forming and solidifying a part employing specialized tooling. This multi-step process is labor intensive, time-consuming, and prone to quality variations due to the need for human intervention. 3D printing of FRPs is an emerging field that has focused primarily on thermoplastic polymers with mostly chopped fibers, resulting in limited stiffness and tensile strength of composite parts, therefore providing little opportunity to create industrial components with enhanced performance. The present proposal aims to overcome these limitations by researching and developing a robotic direct extrusion 3D printing system capable of 3D printing continuous fiber-reinforced plastics to produce parts of industrial relevance and performance. The study will also develop sensors and manufacturing data analytics systems to ensure in line quality control of printed parts by identifying and developing (i) sensors to detect and mitigate part distortion, (2) systems to monitor the continuous fiber morphology in the part, and (iii) actively control the height of deposited layers. The project will also create special computer aided manufacturing strategies, for example, to provide two-dimensional weave capacity for 3D printed parts with true five axis movement for supportless part printing.