Summary of this article

This article presents the following three practical metamaterial design examples that can be applied to today's manufacturing industry.

(1) Haptic device housing design with vibration control

(2) Design for reduced assembly of moving parts

(3) Material substitution design

Differences between metamaterials research and metamaterials in manufacturing

A Google search for the word "metamaterial" shows a number of papers on the various physical functions produced by complex geometries. The background of these discoveries/inventions is largely due to the spread of 3D printers and other machine tools that instantly materialize 3D data in laboratories of universities and research institutes, creating an environment where researchers can quickly design/analyze and prototype/experiment. However, when such academic metamaterials are used in industrial applications, 3D printers are naturally required, and in most cases, mass production is not possible (because the manufacturing cost is too high). On the other hand, the metamaterials introduced above, which require only holes, do not require special manufacturing equipment and can be mass-produced using conventional manufacturing methods. In fact, there are many metamaterials that can be mass-produced without special manufacturing equipment. However, in most cases, even simple structures cannot achieve the desired functionality without extensive design studies of delicately designed structures.

Nature Architects can propose metamaterials that can be mass-produced using conventional manufacturing facilities, and effectively design a vast number of metamaterials to meet all the constraints and objectives of manufacturing, cost, and the functionality they will produce. (Occasionally, we also offer advanced designs utilizing 3D printers.)

Our metamaterial designs address a variety of physical properties, including vibration isolation, vibration transmission, acoustic isolation, and reduction of assembly of moving parts through controlled deformation. The following are three specific design examples.

① Haptic device housing design with vibration control

Conventional designs with the transducer fixed to the enclosure transmit vibration throughout the entire enclosure, making it impossible to efficiently deliver vibration to the user. Our design incorporates a vibration amplification structure into the housing, which amplifies the vibration by vibrating only certain parts of the housing, allowing the vibration to be amplified and delivered to the user. Therefore, it is possible to

• Reduce the power consumption of the actuator to less than half*.
• Improvement of the user's experience due to vibration
• Battery downsizing and actuator cost reduction

The following are expected to be added value to the system. Such added value can be realized without using special manufacturing or parts assembly, without changing the housing design, and without changing conventional manufacturing facilities.

2 Reduction in the assembly of moving parts

We proposed a design that aimed to improve durability, accuracy, and manufacturing cost efficiency by drastically reducing the assembly of joysticks, which require more than 10 parts in conventional products, to 3 to 4 parts even assuming injection molding.

3) Material substitution design

We developed that use plastics to replace flexibility that previously required rubber or elastomers. Specifically, the cushions of office chairs and other products are constructed with a honeycomb of plastic to achieve the flexibility that disperses body pressure efficiently. By appropriately substituting materials, it is possible to create added value such as lower cost, improved design through better design possibility, improved recyclability, and lighter weight.