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This paper aims to present the methodology and results of the experimental characterization of three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) parts utilizing digital image correlation (DIC).

Tensile and shear characterizations of ABS and PC 3D-printed parts were performed to determine the extent of anisotropy present in 3D-printed materials. Specimens were printed with varying raster ([+45/−45], [+30/−60], [+15/−75] and [0/90]) and build orientations (flat, on-edge and up-right) to determine the directional properties of the materials. Tensile and Iosipescu shear specimens were printed and loaded in a universal testing machine utilizing two-dimensional (2D) DIC to measure strain. The Poisson’s ratio, Young’s modulus, offset yield strength, tensile strength at yield, elongation at break, tensile stress at break and strain energy density were gathered for each tensile orientation combination. Shear modulus, offset yield strength and shear strength at yield values were collected for each shear combination.

Results indicated that raster and build orientations had negligible effects on the Young’s modulus or Poisson’s ratio in ABS tensile specimens. Shear modulus and shear offset yield strength varied by up to 33 per cent in ABS specimens, signifying that tensile properties are not indicative of shear properties. Raster orientation in the flat build samples reveals anisotropic behavior in PC specimens as the moduli and strengths varied by up to 20 per cent. Similar variations were observed in shear for PC. Changing the build orientation of PC specimens appeared to reveal a similar magnitude of variation in material properties.

This article tests tensile and shear specimens utilizing DIC, which has not been employed previously with 3D-printed specimens. The extensive shear testing conducted in this paper has not been previously attempted, and the results indicate the need for shear testing to understand the 3D-printed material behavior fully.

The purpose of this paper is to focus on a morphing architecture, conceived to produce droop nose effect, thus preserving high lift performance and laminar flow.

A numerical approach was adopted. On the base of preliminary aerodynamic requirements, the main aspects of the actuation architecture were defined and then assessed through a genetic approach.

Two different working modalities of mentioned architecture were identified: the former implying the use of an actuator, the latter taking advantage of a tailored elastic element, able to actuate morphing under the action of aerodynamic loads, without the aid of actuators.

The research presented in this work refers to an optimisation process currently tailored on preliminary aerodynamic requirements (leading edge vertical displacement maximisation, leading edge radius increase).

The research shows the possibility of producing morphing on the leading edge zone, actuating droop nose effect on metallic (constant and pice wise thickness) and composite skins.

The purpose of the work is to provide a comprehensive review of the digital image correlation (DIC) technique for those who are interested in performing the DIC technique in the area of manufacturing.

No methodology was used because the paper is a review article.

no fundings.

Herein, the historical development, main strengths and measurement setup of DIC are introduced. Subsequently, the basic principles of the DIC technique are outlined in detail. The analysis of measurement accuracy associated with experimental factors and correlation algorithms is discussed and some useful recommendations for reducing measurement errors are also offered. Then, the utilization of DIC in different manufacturing fields (e.g. cutting, welding, forming and additive manufacturing) is summarized. Finally, the current challenges and prospects of DIC in intelligent manufacturing are discussed.

Additive manufacturing (AM) has emerged over the past years as a key technology in aircraft structural components’ manufacturing. This paper aims to describe the numerical analysis and experimental testing of five wing ribs with different 2D topologies manufactured with polylactic acid (PLA) using the fused deposition modeling technology. The main purpose is to determine the best wing rib topology in terms of strength, stiffness and mass.

Numerical analyses are performed using Ansys Workbench’s static structural analysis for two distinct loading cases. In the first loading, the chord-wise distributed load, resulting from wing lift, is replaced by two equivalent concentrated loads at the leading and trailing edges. This simplification allows the numerical results to be experimentally validated. The second loading has distributed loads applied on the upper and on the lower surfaces of the wing rib to produce a more realistic structural response. Experimental tests are performed with the first loading case to determine maximum displacement and failure loads of the wing ribs studied. SEM is used to analyze fracture surfaces.

From the five different PLA printed wing rib topologies studied, it is found that truss type configurations are the more structural efficient, that is, truss topologies exhibit better specific strength and specific stiffness. Additionally, the limiting factor in the design of these wing ribs is stiffness rather than strength.

The work identifies the kind of structural topologies that are best suited for 2D wing ribs obtained by AM and leads the way to more complex and more efficient structural layouts to be explored in the future using topology optimization coupled with simple Finite Element Analysis (FEA).