Unified approach to the characterization of coupled composite laminates Hygro-thermally curvature-stable configurations

Purpose - The purpose of this paper is to demonstrate new design concepts for 24 classes of laminate, which have been derived as part of an ongoing study on the development of a unified approach to the characterization of coupled laminates. The paper presents a description of each class of coupled laminate. Design/methodology/approach - The paper gives an overview of the desired performance and requirements of a smart leading edge device, its aerodynamic design for the wind tunnel tests and the structural pre-designand sizing of the full-scale leadingedge sectionwhich will be tested in the wind tunnel. Findings - Coupled laminates have potential applications in the design of aero-elastic compliant rotor blades or aircraft wing structures, by introducing tailored extension- twist and/or shear-extension coupling at the laminate level; or in the design of thermally activated morphing structures, by exploiting more complex coupling behaviour. Practical implications - These laminates contain standard cross-ply and/or angle-ply combinations, although double angle-ply laminates are also considered, and correspond to any standard fibre/matrix system with a constant ply thickness throughout. Originality/value - The vast majority of the laminate described possess coupling behaviour not previously identified in the literature.