Analysis and Design of Highly Flexible Morphing Structures

Advancements in the aviation sector have consistently aimed to maximize efficiency through a multi-disciplinary approach, focusing on optimizing both structural and aerodynamic performance. Although modern aerospace structures are engineering marvels, they often lack or limit the flexibility observed in nature—such as the flexible, flapping wings of birds. This contrast underscores a significant opportunity to enhance structural performance without compromising safety. A paradigm shift towards more flexible or morphing structures could open up a new realm of lightweight, adaptive solutions. Rather than resisting sudden, extreme loads, flexible structures adapt by deforming and altering their stiffness characteristics, thereby maintaining safety. Multistable composite laminates are promising candidates for morphing applications, owing to their ability to switch between multiple stable states. By applying external energy, these structures can transition, or “snap through,” from one stable shape to another, a phenomenon extensively explored in aerospace research.

To advance this field, this study proposes the computational analysis and design of small-scale morphing structures. The study introduces a novel morphing component based on multistable fiber-reinforced composites, generated through thermally induced residual stresses. Surface-bonded piezoelectric composite actuators are employed to trigger the snap-through. The study presents refined semi-analytical and finite element techniques, and the findings are validated by manufacturing and testing small-scale morphing elements. Results demonstrate that, compared to conventional morphing structures, the proposed design can reduce energy consumption significantly (more than 60% for the presented design). Looking ahead, the focus has to shift toward extending these concepts for real applications, with the goal of preventing failures while enabling large deformations under extreme loading conditions. Achieving this balance demands a novel approach, integrating state-of-the-art computational and manufacturing technologies. Future efforts will aim to explore the structural design space of flexible stiffness switching structures (S³), unlocking the full potential of adaptive, intelligent, next-generation systems of the future.

Dr. Anilkumar P. M. is a research group leader (postdoctoral researcher) in composite structures at the Institute of Structural Analysis, Leibniz University Hannover, Germany (since April 2023). He completed his PhD at IIT Madras (January 2023) in morphing structures, supported by the PMRF and the DAAD binational PhD program with collaboration in Hannover, along with exchange visits to the Bernal Composite Group, University of Limerick. He holds an M.Tech. from IIT Madras and a B.Tech. from NIT Calicut. He has published extensively in morphing structures, stability of composite structures, and related areas. His research interests include composite materials and structures, smart morphing structures, and buckling/postbuckling analysis.