Review of Variable Camber Wings: Design, Enabling Technologies, and Challenges

Variable camber wings (VCWs) enable continuous adjustment of wing camber. This capability allows aircraft to maintain high aerodynamic efficiency and control performance across diverse flight regimes. As a result, VCWs have emerged as a critical research direction in morphing aircraft technologies. In recent years, advances in flexible composites, smart materials, novel morphing structures, and actuation technologies have significantly promoted the development of VCWs. Wing camber morphing has gradually evolved from traditional discrete deformation to smooth and continuous shape variation. This transition has led to substantial improvements in aerodynamic performance. This review systematically examines the technological evolution of VCWs, with particular emphasis on three key enabling technologies: flexible skins, morphing structures, and actuation systems. Representative studies are classified and comparatively evaluated in terms of their design principles, performance characteristics, and engineering applicability. Furthermore, the trade-offs among deformation capability, load-bearing capacity, geometric continuity, actuation requirements, system mass, energy consumption, and engineering complexity are analyzed. Beyond component-level technologies, this review addresses system integration challenges, including technology compatibility, multiphysics coupling and system-level trade-offs, shape sensing and control, engineering scaling, and lifecycle reliability. Potential pathways through which technologies such as mechanical metamaterials, artificial intelligence and machine learning, and digital twins may enable the future development of VCWs are also discussed. Overall, this review summarizes current VCW technologies and may provide a reference for their progression from concept validation to reliable, maintainable, and engineering-ready aircraft systems.