China: Origami Used to Strengthen 4D Metamaterials Resulting in a Tunable Miura-ori Tube

Chinese researchers explore not only the inspiration of origami designs and structures in science and technology today, but also the uses of 4D printing in a range of industrial applications. Their findings have been recently published in ‘Miura-ori tube metamaterial with tunable dynamic property,’ as they explore how modern structures can be engineered to respond to their environment, whether as components for aerospace, soft robotics, or even oceanographic engineering. The difference in these 4D structures is that their complex structures are created through the stacking of Miura sheets and the tuning of origami metamaterials.

While tunable materials are obviously a commodity in engineering today, thus leading many designers from the 3D realm to that of the 4D, typical structures being created are often overly porous and lack desired overall integrity. These types of structures also cannot be changed once they have been manufactured. To overcome these challenges, the authors suggest the use of origami structures for engineering structures ranging from the nano to large scale.

“The goal of origami is to transform a flat square sheet of paper into an elaborate 3D structure through folding and sculpting techniques,” state the researchers. “It thus has fruitful merits such as easy to fabricate, avoiding the complex assembly, and normally lightweight.”

Geometric modelling of the Miura-ori tube metamaterial: (a) The unit cell of the
Miura sheet, (b) a representative Miura sheet with 4 by 1 unit cells, and (c) tessellating two same Miura sheets to construct a Miura-ori tube metamaterial.

Origami structures in previous research studies have been proven to successfully generate shifts in resonance frequencies, actualize thermal expansion coefficients, tune electromagnetic responses, and even stiffness too. For this study, the authors were able to create two Miura sheets, identically assembled at their open sides, leading to the construction of a Miura-ori tube metamaterial. Numerical calculations were performed to capture both the natural frequency and dynamic properties of the unique metamaterial. A five-step process then ensued in making the Miura-ori tube metamaterials: cutting, moulding, stamping, trimming, and gluing.

The researchers examined the dynamic displacement response regarding harmonic load, realizing that it could be tuned ‘in wide range,’ and especially for both cases 2 and 3.

“The reason why the proposed Miura-ori tube metamaterial can be tuned dynamically has been also qualitatively explained from the theoretical perspective. These results open a new avenue toward lightweight and reconfigurable metamaterials with simultaneously engineered tunable dynamic properties,” concluded the researchers in their paper. “Moreover, unprecedented opportunities for lightweight structures to meet the demands with extremely wide range of tunable dynamic properties will be provided when multiple materials are used to constitute the Miura-based tube metamaterial.”

“Further research will focus on investigating the influences of the damping [50] on the tunable dynamic properties. Moreover, we will attempt to establish the dynamic model of the Miura-ori tube metamaterial by using the spring-mass-damping system [51] and derive the formulations of NNFs and dynamic displacement responses.”

(a) Harmonic load, and (b)-(c) diagrams for the position of the applied load: xOy plane, yOz plane, and xOz plane, respectively.

3D printing may seem like magic—especially at the desktop where users are able to think up a concept in 3D from the comfort of their studio, workshop, or home and then poof! It is delivered right before their eyes from mere digital direction and some filament. 4D printing, however, takes this one step further, making it a continuing point of fascination for technological buffs today as it produces textures not only summoned seemingly out of nowhere by 3D design and printing, but once fabricated they come to life, breathing, moving, and morphing due to temperature and environment.

What makes 4D printing even more exciting is that it is obvious designers and engineers are just at the beginning of transforming industrial applications whether creating metamaterials, printing in powerful mediums like metal, or even bioprinting for regenerative medicine. Find out more about the 4D aspects of metamaterial with tunable dynamic properties here. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com.

. Fabrication of the Miura-ori tube metamaterial. (a) Moulds for creating the Miura
sheets and (b) a representative manufacturing process

Effects of β on the normalized natural frequency when the folding angle, θ, changes
from 50 to 130 degree. (a) a/b=1 (The right panel shows typical unit cells of the benchmark
Miura-ori tube metamaterial when β equals to 20°, 50°, and 80°, marked by A#, B#, and C#, respectively); (b) a/b=2 (The right panel presents typical unit cells of the benchmark Miura-ori
tube metamaterial when β equals to 20°, 50°, and 80°, marked by D#, E#, and F#, respectively).