HORIBA's Challenge at the EXPO 2025 - Water Quality analyzer with New Technology

Almost two months have passed since the Expo 2025 Osaka, Kansai, Japan opened on April 13.
HORIBA is a Bronze Partner of the Signature Pavilion “Future of Life” produced by Professor Hiroshi Ishiguro of Osaka University, a leading expert in android development and robotics. In conjunction with our sponsorship of the Expo 2025 Osaka, Kansai, Japan (hereinafter referred to as "Expo"), we launched the HAKARU MIRAI EXPO 2025 PROJECT internally in July 2022 to promote the Expo project, and have been working on co-creating the pavilion's exhibition and production. In addition, there are developers who worked with the project to think about the Expo through manufacturing and trial-and-error. In this issue, we spotlighted these developers and asked them about the secret story behind the development of the project.

Kameko: The project members asked me if I could develop a pH sensor, one of HORIBA's founding products, using a new technology different from existing products, as part of the HAKARU MIRAI EXPO 2025 PROJECT. I was in charge of developing 100 water quality sensors to be installed in the water basins surrounding the pavilion. These sensors were designed to be placed inside 10 black objects with a hemoglobin motif.

The "Future of Life" pavilion is designed to look as if the building itself is a living organism, with water quality analyzers that resemble sensory organs capturing changes in the water basin's quality, The measurements from these sensors are then expressed as waves of light on the building's exterior.

Hashimoto: In addition to this sensor, I was in charge of how to install other sensors in the pavilion. I was also in charge of mechanical design, including the box for the communication equipment. We discussed the shape and length of the sensor, placement of electrical components, waterproof structure, etc., while communicating among the team members.

Kameko: The biggest challenge was figuring out the "new" aspect. It was difficult to create something innovative with such limited time. Traditional pH sensors have glass response parts, but we discussed whether we could use something different. We considered using technology we had been researching in collaboration with a university. This research involved stainless steel sensors that are easy to customize in shape. Therefore, we thought it might be possible to make them as thin as 1mm, compared to our existing sensors with a minimum diameter of about 3mm. Even though it was a collaborative research project, it hadn't yet reached the stage of practical application, so it was definitely a challenge.

Hashimoto: We had to develop this while handling our regular tasks. With a fixed deadline, managing the schedule and evaluating prototypes right up to the last minute was extremely challenging.

Kameko: I was relieved that we managed to achieve performance suitable for the Expo in time for the handover. Unlike glass sensors, which are fragile and require delicate handwork during manufacturing, stainless steel is more durable, easier to process, and cost-effective. However, slight differences in conditions can significantly affect performance evaluations, so there are still many challenges to overcome before commercialization.

Hashimoto: From a design perspective, the installation location changed from our originally planned water level setting. We received a request to make it adaptable to all water level changes. Since this would be difficult with the original design, we redesigned it by placing the sensor on a float to adjust to water level changes. It was challenging to consider various factors, such as preventing the sensor from hitting the bottom. At the pavilion, the sensors are housed inside black hemoglobin-inspired objects, so we also implemented measures to minimize temperature effects during hot summers. We also made various adjustments considering safety and maintenance as well.

 
Left: Water quality analyzers before covering with black object　　/ 　Right: Water quality sensor of 1 mm fineness

Kameko: It may not be that far in the future, but I believe that the stainless steel sensors we've developed can be used not only for water quality measurement but also for various applications in our daily lives. For example, if they become disposable and anyone can easily screen samples, they could be applied in the field of healthcare (medical care). We still need to overcome many challenges to apply these sensors to such a wide range of uses, but I want to realize this potential and make these versatile products widely available throughout society.

Hashimoto: If we continue to design water quality analyzers with the mindset of "protecting the world's water quality," I believe this will lead to the protection of "life," an important element of the Expo theme, and connect to “a future where all life thrives” through HORIBA's vision of " Analytical and Measurement" technologies.

Kameko: It's rare for an Expo to be held in Japan during one's lifetime, and even rarer for the company I work for to be a sponsor. I feel lucky to have been involved, and I'll always be happy to remember that the sensors I worked on were installed in the "Future of Life" Signature Pavilion.

Hashimoto: I feel proud and confident knowing that something I designed is at the Expo site. Going forward, I'll continue to design with flexibility, responding to requests and demonstrating my adaptability.

Wataru Hashimoto (left)
HORIBA Advanced Techno Co., Ltd.
Custom Product Team, Design Department, Development Division
Joined the company in 2016. Engaged in designing custom water quality meter products.

Yudai Kameko (pictured right)
Core Sensing Team, Advanced Technology Development Department, Development Division
Joined the company in 2020. Engaged in research and development of new water quality sensors.

Both contributed their efforts to the development of water quality meters for the exterior display of the Signature Pavilion "Future of Life."

^{* “HAKARU MIRAI EXPO 2025 PROJECT”
This project was formed by open recruitment across HORIBA group's companies in Japan (HORIBA, Ltd., HORIBA STEC, Co., Ltd. HORIBA Advanced Techno, Co.,Ltd. HORIBA TECHNO SERVICE, Co., Ltd.). It comprises 27 volunteers, regardless of age or company tenure, who wanted to be involved in the Expo. The project team was launched in July 2022, starting activities to envision a future society 50 years from now. In co-creation meetings with other sponsor companies, we discussed the “urban environment” of 2075 and considered HORIBA's future role in society.}

(Date of interview: March 2025)
All content and names of organizations, affiliations, positions, etc. mentioned in the text are those at the time the interview was conducted.

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