Bending the Rules of Hardware Design

Electronics are increasingly taking the form of portable and wearable devices that can follow us wherever we go, or even be worn directly on our bodies. As far as size is concerned, electronic components are now more than small enough to support these applications, and they are inexpensive enough to be incorporated into virtually everything. With these problems essentially solved, it is now factors like comfort and adaptability to new use cases that need more attention from hardware engineers.

At present, the vast majority of electronic components are still rigid, which makes them unsuitable for wearable devices or flexible electronics, such as curved displays. Stretchy options — perhaps made up of elastomers — do exist, however, their electrical performance is far lower than their rigid counterparts. This makes for a difficult trade-off between performance and flexibility, when what we really need is both.

A pair of engineers at Waseda University borrowed concepts from origami (paper folding) and kirigami (paper cutting) to come up with a solution to this dilemma. Using the methods they developed they turned rigid materials into flexible substrates, which allows electronic devices to have the best of both worlds: maximal flexibility and performance.

The team introduced what they call a “kiri-origami” structure. This hybrid design blends the folding strengths of origami with the stretchability of kirigami. Where origami offers rigid, flat surfaces well suited to mounting components, and kirigami enables large-scale deformation by introducing slits, kiri-origami combines these features to create something entirely new.

The technique works by creating a grid of square panels defined by orthogonal cutting lines. These panels are linked by triangular joints with folding lines that act as hinges. When stretched, the square panels rise and rotate, opening slits between them and creating a distinctive Z-shaped geometry around the hinges. The end result is a surface that can stretch into new shapes while still carrying rigid electronic elements, such as LEDs or surface-mount devices.

Of course, moving from theoretical geometry to practical electronics comes with complications. Unlike the idealized rigid-origami model, real materials are elastic, which means panels bend, hinges twist, and stresses distribute unevenly. This often leads to warping and distortion when stretched, threatening both the integrity of the structure and the functionality of mounted components.

To address this, the researchers designed special buffer structures: trapezoidal extensions along the edges of the kiri-origami sheet that connect to clamps during stretching. Acting like springs, these buffers spread tension more uniformly across the structure. By carefully matching the geometry of the buffers to the expected stretched state, the researchers were able to reduce distortion and achieve folding patterns that closely resembled the rigid ideal.

To prove the concept, the team built a stretchable display consisting of more than 500 hinges and 145 mounted LEDs. All the hinges folded in unison, and the device maintained its electronic performance both before and after stretching. This demonstration showed the scalability of the approach, in which complex devices with many rigid parts can be transformed into flexible, adaptable systems without sacrificing electrical quality.

By providing a structural solution to the performance-flexibility trade-off, this technology opens the door to advanced wearable sensors, next-generation curved displays, and even robotics applications where flexible yet durable electronics are needed. Healthcare devices, for example, could benefit from comfortable and high-performing monitors that conform naturally to the human body.