While public awareness about the dangers of air pollution is high, problems arising from noise pollution have captured less attention despite being no less dangerous. Sound barriers, commonly used to limit noise transmission, are often seen enveloping construction sites and roads. While effective, they are heavy, rigid and require significant manpower to assemble.
Seeking to overcome these restrictions, Xiang Yu at A*STAR’s Institute of High Performance Computing, together with colleagues from the National University of Singapore and Hong Kong Polytechnic University, are borrowing concepts from origami, the art of paper folding.
“The strategy here is to use rigid plates and flexible hinges to form what is known as a Miura-ori sheet, which is easily reconfigurable,” explained Yu, the lead author of the study. Miura-ori is the name of a particular fold used in origami. With a reversible, single degree-of-freedom foldability, Miura-ori structures can be folded for easy transportation, then quickly deployed into a 3D structure.
The researchers first used a technique called finite element modeling to evaluate how various properties of an origami sound barrier, such as the folding angles and origami pattern, would affect the acoustic shadow zone, or the area protected from noise. Next, to assess whether their mathematical predictions would hold up in reality, they created miniature 3D-printed prototypes of foldable sound barriers, varying the folding configurations and recording the actual acoustic performance of each prototype.
Yu’s team also explored incorporating a micro-perforated membrane—a 0.5 mm-thick carbon fiber sheet with 0.42 mm-diameter holes drilled into it—in their origami sound barrier designs. The membrane is attached to the front surface of the origami sound barrier and can enhance the barrier’s sound absorption properties.
“Our work offers fundamental insights into how folding would affect the acoustic performance of sound barriers, and opens up new opportunities for designing innovative origami-inspired acoustic devices,” said Yu.
“Although this study is developed based on a specific type of origami cell—Miura-ori—the vast origami library can enable other designs with particular geometric features that are acoustically beneficial,” he said.
The A*STAR-affiliated researchers contributing to this research are from the Institute of High Performance Computing.