In the relentless pursuit of flexible and stretchable electronics, a novel approach has emerged from the halls of Waseda University that could revolutionize the way these devices are designed and manufactured. Stretchable electronics have become core components in modern technology, embedded within smartphones, smartwatches, curved displays, and wearable sensors. Yet, a fundamental challenge has persisted: the materials that offer flexibility, such as elastomers, inherently exhibit inferior electrical performance compared to traditional rigid materials like metals or semiconductors. This intrinsic trade-off between mechanical stretchability and electronic functionality has driven researchers to seek innovative structural solutions.
Traditional methods to achieve stretchability in electronics often turn to ancient Japanese arts—origami and kirigami. Origami, the art of folding paper, uses carefully engineered hinge patterns to create foldable yet structurally stable configurations. Kirigami, which incorporates strategic cuts along with folds, allows materials to deform more dramatically, enabling extensive stretching and bending. While origami lends itself to the incorporation of rigid, mountable panels, it lacks the range of deformability offered by kirigami. Conversely, kirigami’s expansive slits provide large-area stretchability but impose limitations on mounting rigid electronic components securely. This dichotomy represents a significant engineering bottleneck in stretchable device fabrication.
Addressing this, Professor Eiji Iwase and his collaborator Nagi Nakamura from Waseda University’s Department of Applied Mechanics and Aerospace Engineering have devised an innovative hybrid structure, coined “kiri-origami.” This approach harmoniously blends the folding mechanisms of origami with the cutting strategies of kirigami to craft structures that optimize stretchability without sacrificing the mechanical benefits of rigid components. Their pioneering work was published in the prestigious journal npj Flexible Electronics in June 2025 and stands to set new milestones in stretchable electronics design.
The ingenious kiri-origami framework features a mutually orthogonal cutting line pattern, strategically arranged to synergize deformation with mechanical support. Triangular joint panels, connected by two folding lines acting as hinges, reconcile two adjoining square panels formed by the cuts. Upon stretching from a flat baseline, these square panels elevate and rotate, enabling the formation of slits and culminating in a distinctive Z-shaped configuration around the hinges. This morphing not only facilitates a remarkable degree of stretch but also permits the simultaneous mounting and movement of rigid electronic components—previously a significant limitation in kirigami designs.
Idealized kiri-origami structures, characterized as rigid-origami, assume perfectly rigid panels with frictionless hinge rotation. However, real-world applications encounter panel deformation and the influence of elastic repulsive forces within flexible electronic substrates. To realistically capture these phenomena, the research team developed what they term an “elastic origami model.” Through experimental uniaxial stretching tests on rectangular models of this elastic origami, the researchers observed deviations from the rigid model predictions. Specifically, the fixed clamping edges and non-uniform tension distributions led to distortions, highlighting important mechanical factors that must be addressed for practical device deployment.
To counteract the detrimental effects of fixed edges and inconsistent tension, the researchers introduced a novel buffer structure design. These buffer components are trapezoidal extensions strategically connected to the edges of the kiri-origami structure and its clamps. The smaller edges of these buffers match the original width of the kiri-origami, while their larger edges are tailored to the target stretched configuration. Under tensile load, these buffers elongate akin to mechanical springs, distributing tension uniformly and enabling the entire structure to deform in a controlled, two-dimensional manner. This advancement enhances the fidelity of mechanical response, aligning experimental outcomes with rigid-model predictions and ensuring device reliability.
Demonstrating the practical viability of their approach, the team engineered a stretchable display integrating over 500 hinges and embedding 145 light-emitting diodes (LEDs). Remarkably, every hinge folded simultaneously without compromising the device’s function, underscoring the method’s potential for scalable, complex electronics. This feat not only showcases the robustness of the kiri-origami design but also highlights its promise for future applications extending beyond conventional flexible electronics.
Professor Iwase underscored the wide-reaching implications of this technology, emphasizing that it paves the path for next-generation wearable sensors, curved displays, and dynamic actuators in robotics and human-assistive technologies. The kiri-origami structure negates the historical compromise between flexibility and electronic performance, enabling the integration of traditional high-performance materials into highly deformable frameworks. This could drastically expand the landscape of wearable and implantable devices, enhancing user comfort, device durability, and overall functionality.
One of the standout technical triumphs of this study is the ability of the kiri-origami design to maintain uniform tension during stretching, vital for electronic stability and longevity. Previous methods struggled with uneven strain distributions leading to material fatigue or electrical failure. The buffer structure, by functioning as an adaptive spring, mitigates these issues and embodies an elegant solution fusing structural mechanics with electronic engineering.
By integrating rudimentary mechanical principles from age-old Japanese arts into cutting-edge materials science, this approach redefines the future of electronic device fabrication. It resonates particularly well in the context of expanding fields such as soft robotics and biomedical instrumentation, where devices must conform reliably to complex, dynamic bodily shapes while maintaining sophisticated functionality.
Furthermore, the scalability of the kiri-origami technique marks a crucial advance. The capacity to fabricate devices with large numbers of repeating units suits mass production and broad deployment. This opens avenues for customizable stretchable electronics tailored to user-specific geometries, from flexible displays that seamlessly curve around wrists and fingers to sensors that adapt to unpredictable human body movements.
The breakthrough reported by Iwase and Nakamura offers a compelling paradigm shift, demonstrating that the limitations of material properties can be surmounted through innovative structural engineering. Their contribution stands as a testament to interdisciplinary synergy, where mechanical design principles align with materials science to unlock new technological horizons.
Looking ahead, this innovation holds the promise of transforming not just consumer electronics but also healthcare diagnostics and robotic assistance systems. Stretchable, high-performance electronic platforms energized by kiri-origami structures will likely become foundational enablers of futuristic applications, catalyzing advances in personalized medicine and bio-integrated robotics.
As this research gains traction, it may inspire further explorations into hybrid fold-and-cut geometries, adaptive mechanics, and integrated system design, inspiring a fresh wave of innovations that blend historical artistry with modern scientific tenacity.
Subject of Research: Not applicable
Article Title: Stretch-based kirigami structure with folding lines for stretchable electronics
News Publication Date: 5-Jun-2025
Web References: https://doi.org/10.1038/s41528-025-00409-4
References: Nakamura N, Iwase E. Stretch-based kirigami structure with folding lines for stretchable electronics. npj Flexible Electronics. 2025;9:Article 4. https://doi.org/10.1038/s41528-025-00409-4
Image Credits: Professor Eiji Iwase, Waseda University
Keywords
Electronics; Wearable devices; Applied physics; Applied sciences and engineering; Sensors; Robotics; Mechanical engineering; Materials science
