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The time difference of arrival (TDOA) method has traditionally proven effective for locating acoustic emission (AE) sources and detecting structural defects. Nevertheless, its applicability is constrained when applied to anisotropic materials, particularly in the context of fiber-reinforced composite structures. In response, this paper introduces a novel COmposite LOcalization using Response Surface (COLORS) algorithm based on a two-step approach for precise AE source localization suitable for laminated composite structures. Leveraging a response surface developed from critical parameters, including AE velocity profiles, attenuation rates, distances, and orientations, the proposed method offers precise AE source predictions. The incorporation of updated velocity data into the algorithm yields superior localization accuracy compared to the conventional TDOA approach relying on the theoretical AE propagation velocity. The mean absolute error (MAE) for COLORS and TDOA were found to be 6.97 mm and 8.69 mm, respectively. Similarly, the root mean square error (RMSE) for COLORS and TODA methods were found to be 9.24 mm and 12.06 mm, respectively, indicating better performance of the COLORS algorithm in the context of source location accuracy. The finding underscores the significance of AE signal attenuation in minimizing AE wave velocity discrepancies and enhancing AE localization precision. The outcome of this investigation represents a substantial advancement in AE localization within laminated composite structures, holding potential implications for improved damage detection and structural health monitoring of composite structures.

Experimental demonstration and performance evaluation on a shape-adaptive carbon composite full-scale hydrofoil manufactured using automated fibre placement (AFP) are presented in this paper. The experimental responses of the hydrofoil are validated with the finite element analysis (FEA) tools. The static performance of the hydrofoil was investigated using quasi-static cantilever load, whereas the dynamic response was studied using experimental modal analysis (EMA) to assess the structural quality of the manufactured hydrofoil. The variation between predicted and experimental modal and bending stiffness was found to be within 20%. Structural strains were also monitored using a network of distributed fibre optic sensors on the surface as well as embedded in conjunction with a network of strain gauges. The outcomes from this work demonstrates a framework of numerical analysis and experimental validation techniques using multiple sensors, which will pave the way towards further demonstrating the structural adequacy and performance of such hydrofoil, made of automated techniques and embedded with optical fibre sensor systems.