drawing from japanese paper cutting art, the auxetic pavilion filters sunlight like a tree

auxetic pavilion by Masaaki Iwamoto and Mika Araki

Located in the courtyard of a Japanese college campus, the Auxetic Pavilion by Masaaki Iwamoto Laboratory and Mika Araki Laboratory demonstrates a new way to create porous, free-form, three-dimensional surfaces. The small but innovative project is an application of a geometric structure called auxetics and uses the plasticity of metal plates to create a curved surface with a minimum of material and labor.

The incisions pattern in the metal plates, reminiscent of the Japanese paper cutouts in ‘Kirigami’, creates a striking roof that filters sunlight and shines like a rippling water surface. The resulting effect reminds the viewer of sunlight falling through the leaves of a tree. The project employed a biomimetics approach, a collaboration between designers and botanists, and was inspired by the cellular morphological changes of floral organs.

the innovative project is an application of a geometric structure called auxetics

all images courtesy of Yashiro Photo Office

about auxetics

‘Auxetics are geometric patterns consisting of a number of periodic incisions in a flat surface, which, when stretched laterally, also expand longitudinally,’ Masaaki Iwamoto Laboratory (find more here) and Mika Araki Laboratory explain. ‘In our project, this mechanism was applied to a metal plate.’ 

First, a 1 mm thick stainless steel plate is laser cut with a geometric pattern. This steel plate is then loaded and plastically deformed to produce the desired porous surfaces. This forming process can be carried out by hand, without formwork or jigs, and is therefore economical and resource-saving.

the structure uses the plasticity of metal plates to create a bendable surface with minimum materials

To understand the relationship between the incision pattern and the curved surface produced, the designers performed material experiments in the laboratory and developed a simulation method based on a nonlinear analysis of plastic deformation. This research allowed them to predict the incision pattern required to produce the desired surface shape.

The curved auxetic surface can be an architectural element with a variety of potential applications, such as controlling solar gain, harnessing daylight, and promoting ventilation. By changing the cutting pattern, the opening rate of the panels can be freely adjusted within a range of 5% to 50%. The pavilion can change its shape according to the climatic conditions of the site and control light and heat to create a comfortable space in the shade.

the incisions pattern in the metal plates creates a striking roof that filters sunlight

the incisions pattern in the metal plates are reminiscent of the Japanese paper cutouts in ‘Kirigami’

the pavilion can be bent to change its shape according to the climatic conditions of the site

by changing the cutting pattern, the opening rate of the panels can be freely adjusted within a range of 5% to 50%

project info: 

name: Pergola of Auxetic Structure
designers: Masaaki Iwamoto Laboratory, Kyushu University, Mika Araki Laboratory, Kwansei Gakuin University
project team: Masaaki Iwamoto, Mika Araki, Yuri Iwata, Miki Katsuki, Hanano Tanaka, Hirotaka Ujioka, Kai Morinaga
botanist: Akitoshi Iwamoto, Kanagawa University
collaborator: ICADA, Graph Studio
metal work: Ryouyu Kougyo
location: Fukuoka, Japan
photographer: Yashiro Photo Office