Digital
Manufacturing

The surface of sharkskin is covered with microscopic scales invisible to the eye. Scientists believe it is the shape and arrangement of these scales in a riblet-like pattern that reduces the effect of turbulence, allowing sharks to swim with great speed and efficiency. Riblet processing can therefore be called a biomimetic technology as it mimics nature by creating a similar structure on the surface of man-made materials.

Nikon’s riblet-processing machines can handle a wide variety of materials, including metals, resins, and fiber-reinforced plastics. Equally important, they can create riblets on complex three-dimensional curved surfaces. No matter how complex the shape, we can create appropriate riblet patterns with the desired depth, width, and direction. Riblet processing has already been employed to improve the performance and fuel efficiency of racing sailboats and various aircraft. Its use is expected to be expanded to cargo aircraft in the future. The propulsive force of ships and aircraft is significantly impacted by the frictional resistance of their body surfaces in the water and air through which they travel, so the introduction of technology that effectively reduces it is increasingly attracting attention.

As a case study, one of the major airlines in Japan, ANA, has installed Nikon‘s unique riblet film on two ANA Green Jet specially painted airliners for testing, that started operation from October 5, 2022. This coating reduces air resistance and is expected to improve fuel efficiency by about 2%, for savings of approximately 8 billion Japanese yen, equivalent to USD 55 million (November 10, 2022 exchange rate). Improving fuel efficiency not only lowers costs, but also helps reduce CO2 emissions. The ANA Group has set an environmental target of “Net-zero CO2 emissions from aircraft operation by the 2050 fiscal year” and is expected to reduce such emissions by 300,000 tons annually. Now that realization of carbon neutrality has become an important social issue, riblet processing is attracting great interest as a key technology to achieve this.

Nikon is combining riblet-processing technology and mobility to make it available where it’s most needed. By incorporating a camera as the eyes and laser as the main tool in a mobile robot, it applies the laser accurately to the target position while capturing the object with the camera, generating riblets even over a huge structure such as a windmill’s blade. A camera and a laser can also be incorporated in a drone to operate riblet processing on a target situated high up. Autonomous control is possible by using the results supplemented by the eyes for pre-prediction and post-confirmation, and these are performed fully automatically. With these technologies, Nikon envisions a future when riblets can be applied to wind turbines that are constructed in harsh environments such as in the mountains or at offshore sites.

Although additive-manufacturing technology itself has existed since the 1970s, its use did not spread widely because of the high cost and low versatility of the 3D process. In recent years, however, technological innovations in additive manufacturing have made it possible to create molds with high precision, high speed, and low cost, and 3D printing is now used in the manufacture of a wide range of products, including engine parts, tools, and artificial joints for medical use.
In the future, growth is expected in an even broader range of fields such as aerospace, where heat resistance, durability, and corrosion resistance are required, and electric vehicles that are lightweight — extending their travel range.

Nikon’s metal 3D printer operates by using lasers to melt metal powder and build objects, benefiting from Nikon’s optical technology developed over 100 years. Moreover, the precision positioning expertise developed in semiconductor lithography equipment and image technology for monitoring phenomena occurring during laser processing can be harnessed.

This technology enhances durability through the repair and reuse of previously discarded parts, as well as for satellite-related components that require strength and precision. Nikon aims to contribute to solving societal challenges and provide new value to the future of manufacturing industries such as aerospace, energy, and automotive, all while addressing issues related to heat resistance and earthquakes.