Maintaining Multistability in Cured Shapes of Series-Connected Unsymmetrical Laminates with Clamped Edges
P. R. MANU, B. N. RAO, P. M. ANILKUMAR
Abstract. Adaptive structures are designed to undergo controlled shape changes in response to varying functional requirements, making them highly versatile for advanced engineering applications such as aerospace and space structures. Within this domain, unsymmetrical laminates have gained considerable attention due to bistability arising from residual thermal stresses generated during the curing process. However, the practical applications of the cured shapes of unsymmetrical laminates are often restricted due to the possibility of only two room-temperature equilibrium states. By connecting multiple bistable laminates in series, it becomes possible to realize surfaces with a high degree of multistability. The degree of multistability of such connected laminates is strongly influenced by boundary conditions, which play a critical role in shaping the stability landscape. While most theoretical models in the literature assume simplified center-fixed boundary conditions, such idealized constraints are rarely representative of real-world applications. This study aims to bridge this gap by investigating the influence of boundary constraints on the multistability of series-connected composite laminates. Specifically, a one-end-fixed boundary configuration is analyzed, in which one end of the laminate is clamped. The study shows that the clamped edge imposes significant mechanical constraints that limit bending parallel to the clamped edge. A solution to retain multistability could be the use of a transition region, ensuring that a laminate can recover its original multistable state even when one edge is clamped. Such a transition region helps preserve the multistability of the connected laminate. The results offer new insights into how fixed boundary conditions affect the design space, thereby deepening the understanding of multistable laminates and advancing their application potential in morphing systems.
Keywords
Finite Elements, Boundary Conditions, Morphing, Multistability
Published online 7/20/2026, 5 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: P. R. MANU, B. N. RAO, P. M. ANILKUMAR, Maintaining Multistability in Cured Shapes of Series-Connected Unsymmetrical Laminates with Clamped Edges, Materials Research Proceedings, Vol. 69, pp 1331-1335, 2026
DOI: https://doi.org/10.21741/9781644904251-231
The article was published as article 231 of the book CEAS – AIDAA Conference 2025
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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