Maintenance and inspection work in underwater, flammable-gas, and radiation environments requires drive systems that can reduce electrical ignition and hydraulic oil leakage risks.
At ROBOT TECHNOLOGY JAPAN 2026, NACOL CO., LTD. presented an extreme-environment work robot driven by water hydraulics and built using the company’s pumps, valves, and cylinders.
Its newly developed proportional water-hydraulic valve enables stepless control of flow rate and direction, supporting smoother robot-arm movement, while the 4 MPa pump allows a single cylinder to lift and lower loads of up to 200 kg.
NACOL also develops valve-control software in-house, supporting potential applications in marine structures, chemical plants, nuclear facilities, infrastructure inspection, and disaster-response operations.
Challenges Addressed
Solutions
FAQ
Why does the robot use water instead of electricity or hydraulic oil?
In what types of environments can the robot operate?
How much weight can the water-hydraulic system handle?
View video transcript
As a manufacturer of water pressure equipment,we make water pumps, valves, cylinders, and so on.
We combined our equipment to create this robotic arm.
Its key feature is that it uses only water, so there is no electricity or oil whatsoever.
This allows us to create robots that can operate in various environments, such as underwater, in the sea, around flammable gases, or in radioactive environments.
Normally, with conventional water pressure, it’s either water flowing or no water flowing- an all-or-nothing situation.
However, the proportional valve we have developed allows us to seamlessly change not only the direction of the water but also the flow rate.
This proportional valve allows the robot to move freely and seamlessly, resulting in smooth movements.
Furthermore, the pump has 4M of pressure, so, for example, this single cylinder can lift and lower an object weighing 200kg.
We primarily manufacture hydraulic equipment,but we also develop simple robots like this one, as well as software for operating valves like these, in-house, so please feel free to contact us.
Contact the Company
NACOL CO., LTD.
Available Languages
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