While the monitoring techniques employed are well established in other fields, their application to the novel processes of ultrasonic and resistance welding of composites is innovative. This study details the adaptation of these techniques to monitor the essential parameters that influence the quality of welds in composite materials within the context of the MFFD (Multi-Functional Fuselage Demonstrator) during the WELDER project. This article presents findings from the application of a sophisticated monitoring system to new welding processes for composites, demonstrating significant enhancements in process control, quality assurance, and operational safety. In ultrasonic welding, temperature, speed, power, amplitude, and displacement were monitored, whereas in resistance welding, voltage, load, and temperature were tracked. This comprehensive data collection is crucial due to the sensitivity of composite materials to welding parameters, which directly affect the integrity and performance of the final product. The data transmission utilized the OPC UA protocol, ensuring secure, reliable real-time data flow to visualization interfaces in safe environments. The integration of real-time monitoring and advanced data analysis helps in identifying potential defects during the welding process, thereby enhancing both the reliability and efficiency of composite welding. The results underscore the potential of these technologies to advance the manufacturing practices for high-performance composite materials in the aeronautics field.

Out-of-Autoclave technologies are emerging as cost-effective alternatives to autoclave cure prepreg. However, their implementation in aerospace industry is still presenting many challenges. A common problem is the shape distortions that results in geometry mismatches with the tool. A way to avoid this and ensure a good final quality part is identifying the mechanisms that induce these deformations and optimize the manufacturing process of each component with the aim of reducing the production of faulty parts. The main objective of ELADINE project is to provide a method for shape distortions prediction on composite integral structures using an experimental-numerical approach. Different manufacturing parameters were monitored using Fiber Bragg Grating (FBG) sensors and DC-dielectric (DC) sensors and the resulting part geometry was examined by means of 3D coordinate analysis. The study performed for LRI (Liquid Resin Infusion) manufactured parts and the scenarios considered for the calibration of a Finite Element Method (FEM) based simulation tool are presented in the article. The resulting model will be implemented in a sub-scale demonstrator and, eventually, in a full 7-meter composite wing-box.

ELADINE project is aiming to implement a numerical tool that can reduce reoccurring costs of low-volume production in composite manufacturing of primary structural elements and thus reducing overall manufacturing effort and carbon emissions. A primary goal of this project is to eliminate tolerance non-compliancy in the manufactured structures caused by natural and unavoidable post-manufacturing distortions, typical for composite materials. These distortions might render otherwise qualitative components unusable due to their final geometry. Objectives of the Numerical model validation are: To understand the dominant factors which affects the spring-in phenomenon. To provide the simulation tool with the required values of the properties that influence on spring-in. To verify the simulation tool ability to predict spring-in for a variety of conditions. To develop a procedure of adapting and embedding sensors (dielectric and fiber optic) to obtain proper, useful and accurate signals of the manufacturing parameters (T, degree of cure, strain). To develop interpretation procedures of the signal/curves of sensors to obtain on-line process monitoring information. To obtain the data to feed and develop the numerical tool able to estimate the component distortions after its manufacturing, a combination of Fiber Optic Sensors (FOS) based on Fiber Bragg Grating (FBG) technology, Dielectric Curing sensors (DC) and 3D scanning were used to monitor the composite coupon manufacturing and the distortions the days after being demoulded. During the manufacturing process embedded FBGs and DC sensors were used to monitor the coupon temperature and strain distribution and resin curing evolution. After the manufacturing and the demolding, the distortions evolution were monitored by the embedded FBGs and by 3D CMM measurements. In the ELADINE project, the distortion monitoring was made to two Out-of-Autoclave manufacturing technologies: liquid resin infusion (LRI) and oven cured pre-preg. For both material systems, slightly curved coupons and C-shaped coupons were the geometries selected as representative for the Skin and spars of the wing box. The Skin coupon was curved panel with a 1475 mm radius (with edge rise of 7,65 mm) that was thought to best replicate the wing profile geometry. The C-spar coupon geometry selected for the study was a non-tapered spar section with two different angle with radius of curvature of 5mm and 12mm. This geometry was chosen to simplify measuring and comparisons with wing demo. Furthermore, three different thickness are studied for the Skin coupons and two for the C-spar coupons which were selected from different zones along the wing. Moreover, a C-spar coupon with variable thickness was studied, as a simulation of the transition between zones with different thickness in the wing. In this dataset, the data from the FBGs, DCs and 3D CMM meassurements for the LRI manufacturing process and spring_in distortions monitoring is included.

ELADINE project is aiming to implement a numerical tool that can reduce reoccurring costs of low-volume production in composite manufacturing of primary structural elements and thus reducing overall manufacturing effort and carbon emissions. A primary goal of this project is to eliminate tolerance non-compliancy in the manufactured structures caused by natural and unavoidable post-manufacturing distortions, typical for composite materials. These distortions might render otherwise qualitative components unusable due to their final geometry. Objectives of the Numerical model validation are: To understand the dominant factors which affects the spring-in phenomenon. To provide the simulation tool with the required values of the properties that influence on spring-in. To verify the simulation tool ability to predict spring-in for a variety of conditions. To develop a procedure of adapting and embedding sensors (dielectric and fiber optic) to obtain proper, useful and accurate signals of the manufacturing parameters (T, degree of cure, strain). To develop interpretation procedures of the signal/curves of sensors to obtain on-line process monitoring information. To obtain the data to feed and develop the numerical tool able to estimate the component distortions after its manufacturing, a combination of Fiber Optic Sensors (FOS) based on Fiber Bragg Grating (FBG) technology, Dielectric Curing sensors (DC) and 3D scanning were used to monitor the composite coupon manufacturing and the distortions the days after being demoulded. During the manufacturing process embedded FBGs and DC sensors were used to monitor the coupon temperature and strain distribution and resin curing evolution. After the manufacturing and the demolding, the distortions evolution were monitored by the embedded FBGs and by 3D CMM measurements. In the ELADINE project, the distortion monitoring was made to two Out-of-Autoclave manufacturing technologies: liquid resin infusion (LRI) and oven cured pre-preg. For both material systems, slightly curved coupons and C-shaped coupons were the geometries selected as representative for the Skin and spars of the wing box. The Skin coupon was curved panel with a 1475 mm radius (with edge rise of 7,65 mm) that was thought to best replicate the wing profile geometry. The C-spar coupon geometry selected for the study was a non-tapered spar section with two different angle with radius of curvature of 5mm and 12mm. This geometry was chosen to simplify measuring and comparisons with wing demo. Furthermore, three different thickness are studied for the Skin coupons and two for the C-spar coupons which were selected from different zones along the wing. Moreover, a C-spar coupon with variable thickness was studied, as a simulation of the transition between zones with different thickness in the wing. In this dataset, the data from the FBGs, DCs and 3D CMM meassurements for the LRI manufacturing process and spring_in distortions monitoring is included.

The additive manufacturing of high-performance thermoplastics, including high-temperature materials and continuous fiber reinforcement, are extensively being developed worldwide. In this work, we combined laser-assisted in situ consolidation tape laying and fused filament fabrication to manufacture a 100% thermoplastic stiffened panel in three stages with innovative designs using LMPAEK-PEKK carbon fiber-reinforced polymers. The overprinting of gyroid structures on top of ATL laminates assisted by lasers have shown very good adhesion. Mechanical characterization by flatwise and four-point bending tests have shown tensile strength in the range of 10 MPa (flatwise) and 889 MPa (four-point bending). Tomography analysis shows the optimization roadmap to enhance mechanical properties by improving temperature management during manufacturing.