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The continuous resistance welding (CRW) process consists of an end-effector which moves along the length of a weld seam, heating a conductive implant while compacting the joint locally throughout the melt and solidification stages of the thermoplastic material. The performance of the joint has been shown to be highly dependent on the process temperature at the weld interface; however, this cannot be measured directly during the process in a non-invasive manner. Other parameters such as boundary conditions, substructure properties, or part geometry may vary along the length of the weld. As such, a physics-based simulation is developed founded upon an "MSTEP" framework which defines how the materials (M), shape (S), tooling (T), and equipment (E) interact to determine the process (P). Detailed finite element (FE) models are developed for thermal analysis based on the weld geometry, boundary conditions, and previously developed and validated melt/crystallization models for the thermoplastic matrix. Experimental CRW tests are presented to validate simulations and calibrate suitable control variables. [ABSTRACT FROM AUTHOR]

Comparing manufactured parts to their engineering specifications is the basis for Quality Control. Traditionally, Geometric Dimensioning and Tolerancing (GD&T) standards define how engineering tolerances are used for generating fabrication specifications. Due to the complexities inherent to the composite layup process, Automated Fiber Placement (AFP) machines require a new paradigm of quality control. In addition to the traditional finished part dimension and quality reports, the AFP process requires a ply-by-ply inspection of the as-built laminate to ensure that each laydown remains within the manufacturing allowable specifications. To address this problem, Fives and the National Research Council Canada have proposed an In-Process Inspection system based on Optical Coherence Tomography (OCT) technology capable of performing highresolution surface profilometry and automatic alignment of the as-manufactured measurements to the asdesigned engineering model. With both an accurate surface profile and positioning of the measurement data in the CAD design reference, the differences can be analyzed to detect manufacturing anomalies and minimize process variability. Later on, this information has the fidelity required for an exact digital transformation of the process. This paper will review a few aspects of the Measurement System Analysis performed to validate the sensor's reliability as well as review the high level methodology undertaken to establish the relationship between the IPI system's sensor and the machine tool center point during fabrication. Finally, examples will be used to demonstrate the approach to obtain course, ply, and laminate level aggregations. [ABSTRACT FROM AUTHOR]