## 4 Summary and Conclusions
The inherent trade-off between softness and durability also presents limitations, as highly deformable materials may experience fatigue, hysteresis, or slower dynamic responses. For example, repeated folding or stretching in pneumatic or origami-based systems can degrade long-term performance, and certain active mechanisms demand high energy inputs that are not always feasible in real-world settings. Future progress will likely rely on innovations across multiple disciplines. Developments in materials science--such as the creation of fast-responding elastomers with improved fatigue resistance--alongside advanced fabrication techniques like 3D or 4 Dprinting, and integration strategies from soft robotics and flexible electronics, are expected to be critical. Enhanced computational tools will also aid in the predictive design and optimization of complex acoustic structures. At the same time, it is essential to acknowledge the underlying trade-offs between traditional and soft acoustic metamaterials. Although structural compliance affords exceptional tunability and adaptability, it invariably entails heightened fabrication complexity, diminished mechanical integrity, and reduced energy efficiency--challenges whose resolution will be instrumental in realizing versatile, high-performance acoustic systems. To translate these multidisciplinary advances into practical devices, researchers are actively working on modeling and tuning methods. Recent studies have begun to reflect such interdisciplinary advances, particularly in how SAMs are designed, modeled, and tuned for functional performance. For example, [PERSON] et al. introduced a magnetically tunable membrane-type metasurface, employing geometric nonlinearity to achieve broadband control over reflection-based acoustic wave manipulation [37]. [PERSON] et al. proposed a thermally reconfigurable soft-stiff hybrid metamaterial and conducted finite element analysis using a coupled piezoelectric-circuit-structural-acoustic model, with all materials modeled as linear and isotropic [99]. [PERSON] et al. developed a reconfigurable acoustic waveguide based on origami-inspired rigid structures and analyzed directional sound propagation through simplified acoustic simulations, assuming rigid boundaries and linear wave behavior [104]. While each study incorporated specific elements such as boundary-applied magnetic forces or geometric nonlinearity, most adopted linear elastic material models and frequency-domain analyses. Despite differences in actuation mechanisms and structural designs, all three approaches shared common modeling simplifications, including static deformation assumptions, linear elasticity, and limited multiphysics coupling. In particular, material and structural softness in SAMs leads to modeling challenges that involve both geometric nonlinearity and stimulus responsiveness. To address this complexity, the reviewed studies adopted simplified strategies, such as analyzing static deformation states or omitting time-dependent responses. Nevertheless, they sought to capture the essential system behavior by incorporating structure-acoustic interactions. For future work, enhanced modeling frameworks that integrate nonlinear, time-dependent behavior and full structure-acoustic coupling will be crucial for more accurate and predictive simulations of soft and reconfigurable metamaterials. J-HL and H.K. Conceptualization, methodology, investigation, writing--original draft preparation, writing--reviewing and editing, visualization. E.K. : investigation, writing--original draft preparation. M.-W.H. : conceptualization, supervision. All authors have read and agreed to the published version of the manuscript. This study was supported by the commercialization promotion agency for R&D outcomes grant funded by the Korea government (MSIT) (RS-2025-02315174). Not applicable. This work was supported by the Dongguk University Research Fund of 2024. The authors declare no conflicts of interest.