We successfully measured gas concentrations inside sewer pipes using a drone equipped with the compact gas detector "GW-3."

Blue Innovation Co., Ltd. is known as a pioneering service provider in the drone industry. The company provides solution services that leverage drones and robots to solve various societal and business challenges.
In 2020, Blue Innovation collaborated with TOKYO ENGINEERING CONSULTANTS CO.,LTD. to conduct a proof-of-concept experiment. This involved mounting Riken Keiki portable gas detector, the GW-3, onto the ELIOS 2 spherical drone designed for indoor inspections. This recorded the industry's first successful measurement of gas concentrations inside sewer pipes by using a drone.
Today we interview with Mr. Yamaguchi, Yudai of the Sales Department and Mr. Endo, Masatoshi of the Business Promotion Department about the company's activities, the reasons for selecting Riken Keiki products for their proof-of-concept experiments, and future challenges.

First, please introduce us about Blue Innovation's business activities.

Our company provides solution services for business automation and digital transformation utilizing drones and robots across four key areas: “Inspection,” “Education,” “Port,” and “Next.”

The core is our proprietary drone/robot device and data integration platform, “BEP” (short for Blue Earth Platform; hereinafter “BEP”). This platform coordinates multiple drones and robots to execute complex tasks, focusing on functions such as “operating robots,” “gathering information,” and “managing information.”

We do not develop drones or robots in-house. Instead, we specialize in selecting the optimal existing products tailored to our clients' problem, and we develop and provide customized packages by integrating BEP's functionalities. We also focus on initiatives for the societal implementation of drones and robots in collaboration with many partners. 
In 2023, we newly listed on the Tokyo Stock Exchange Growth Market.

What kind of solution services do you provide in the inspection field?

We primarily conduct inspections and surveys of the inside and outside of facilities and equipment.
Targeted facilities include petrochemical plants, power plants, steel mills, sewage treatment plants, construction sites, manufacturing plants, transmission lines, and public infrastructure.
Inspections and surveys in high places, confined spaces, or environments with toxic substances involve risks, but using drones increase worker safety.

Inspecting and surveying hazardous areas typically require at least two workers as well as specialized equipment, which can drive up operating costs.
Therefore, drone-based inspection and surveying is a key feature that contributes to reducing operational costs and resolving labor shortages.

What challenges were encountered during the sewer inspection?

Countless microorganisms exist inside sewage, and their proliferation creates an oxygen-depleted environment. Therefore, whenever workers enter manholes for sewer inspections, oxygen levels must be measured each time to confirm its safety. Conventional measurement methods could only assess concentrations near the manhole entrance, and confirming the internal oxygen concentration was an urgent priority.

Please share the reason why Riken Keiki's gas detector was selected for the proof-of-concept experiment.

The extremely lightweight design and built-in data logger function were the deciding factors. Since the ELIOS 2 spherical drone for indoor inspections has a load capacity close to zero, weight was a critical consideration during our selection. Since Riken Keiki also promoted it as the “world's smallest and lightest,” it immediately became our top candidate for the device. Additionally, the recording allows us to review data after drone operation.

Prior to deployment, we conducted test flights with gas detectors mounted on the drones to verify their maneuverability. Riken Keiki kindly accompanied us throughout the process and provided several units of the equipment, offering support at every stage.

Please tell us about the story behind conducting the proof-of-concept testing and the experimental methods used.

The inquire came from a customer facing “being unable to ensure worker safety and inspect the interior of sewers.” While looking for drones capable of flying in narrow spaces, they found our company.

In the experiment, a gas detector was mounted on the upper front section of the ELIOS 2 spherical drone for indoor inspections. The drone flew approximately 100 meters into the rainwater pipeline to measure gas concentrations. The first measurement confirmed a 0.3% (3,000 ppm) decrease in oxygen concentration compared to normal levels. However, the second measurement showed no change in the data.

How was the data acquired?

We collected data by synchronizing the drone's flight start time with the starting time of gas detector's measurement. Since the drone's flight records include location data, we were able to determine the relationship between the drone's position and gas concentration levels.

Please tell us the results obtained from this trial.

One achievement was the ability to measure gas concentrations inside sewer pipes without entering.
On the other hand, it was also found that the strong wind generated by the drone stirs up the air. As its evidence, oxygen concentration decreased during the first measurement, and no change in data was observed during the second measurement. Therefore, gas concentration measurement by drones can be considered useful for the purpose of “safety confirmation.”

How do you think about our support so far.

We truly appreciate your consistently thoughtful and attentive responses to our inquiries. While we are drone specialists, our knowledge of gas detectors is insufficient. We frequently have questions regarding their usage and are always greatly supported.

We have the chances to accompany you on-site, and we are highly satisfied with your support service.
We are also active in regional areas and Riken Keiki's nationwide network of sales offices provides us with tremendous reassurance.

What features do you expect from our gas detectors?

As the field tests, gas detectors mounted on drones are affected by the air agitation. Therefore, incorporating a function to measure gas concentrations at area distant from the drone should improve its accuracy.

After measurement, the process involves removing the gas detector from the drone, connecting it to a computer via cable, and then reviewing the data on the computer. Therefore, since this requires significant time and effort, a feature that displays gas concentration in real time during drone operation would be greatly appreciated. I believe this would dramatically improve both efficiency and accuracy.

An attachment that securely fixes both the drone and gas detector would be ideal. Currently, we just attach it firmly with hook-and-loop fasteners, and it's not 100% reliable. If we could secure these with screws or similar fasteners, I believe it would completely eliminate any worry about them falling off.

Is there any prospect of drones being used for mandatory gas concentration measurements prior to work inside manholes?

After the trial test, we have received inquiries from various companies. When we explain, the air agitation, many customers decided to abandon implementation. In order to meet customer needs, resolving the issue of the air agitation is a priority to solve.
Furthermore, we believe that the demand would increase significantly if operators could monitor gas concentration levels in real time with pinpoint accuracy during drone operation. We aim to develop solutions by collaborating with our customers and Riken Keiki to resolve these challenges together.

【ELIOS Series – Indoor Inspection Drones】

Developed by Switzerland-based drone manufacturer Flyability, the ELIOS series is designed for indoor inspections and offers outstanding flight performance in non-GNSS environments.
Blue Innovation Co., Ltd. is the sole authorized distributor of Flyability products in Japan.
https://www.blue-i.co.jp/elios3/