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Automated Fiber Placement (AFP) plays a significant role in advanced manufacturing, particularly in the aerospace and automotive industries. AFP technology is of benefit as it enables us to generate layups, based on optimum designs by fiber steering. The primary benefit of AFP is the lower cost through scrap reduction and improved production cycle time as opposed to hand layup methods. However, just as hand layup, AFP also suffers from inherent unintended imperfections. These imperfections could be due to multiple reasons, often the layup imperfections such as gaps and overlaps are studied but enough emphasis is not provided on the defects due to consolidation/curing. Optimized cure cycles are utilized to minimize residual stresses developed during curing, which could affect the mechanical performance of the composites. A continuum-based damage model called the “smeared crack approach” is used to conduct a progressive damage analysis on AFP fabricated coupons where the layup imperfections and consolidation defects are considered simultaneously. 

Fabric draping, which is referred to as the process of forming of textile reinforcements over a 3D mold, is a critical stage in composites manufacturing since it determines the fiber orientation that affects subsequent infusion and curing processes and the resulting structural performance. The goal of this study is to predict the fabric deformation during the draping process and develop in-depth understanding of fabric deformation through an architecture-based discrete Finite Element Analysis (FEA). A new, efficient discrete fabric modeling approach is proposed by representing textile architecture using virtual fiber tows modeled as Timoshenko beams and connected by the springs and dashpots at the intersections of the interlaced tows. Both picture frame and cantilever beam bending tests were carried out to characterize input model parameters. The predictive capability of the proposed modeling approach is demonstrated by predicting the deformation and shear angles of a fabric subject to hemisphere draping. Key deformation modes, including bending and shearing, are successfully captured using the proposed model. The development of the virtual fiber tow model provides an efficient method to illustrate individual tow deformation during draping while achieving computational efficiency in large-scale fabric draping simulations. Discrete fabric architecture and the inter-tow interactions are considered in the proposed model, promoting a deep understanding of fiber tow deformation modes and their contribution to the overall fabric deformation responses.