What is this revolutionary wheel invented by the Ensta engineering school in Brest?



At the origin of this revolutionary wheel case, a request from EDF came to the office of the Ensta Bretagne engineering school in Brest in 2016. The object: to find a way to inspect the metal pipes that carry water from the dams to the turbines, in order to detect potential defects. These pipes are narrow, often inclined (even vertical) and curved. Until then, specialist rope access technicians operated in the dark, in sometimes extreme temperature conditions. The school must provide solutions. “In the process, EDF placed an order for a robot with magnetic wheels, based on the proposals made by our students”, explains Yannick Argouarc’h, teacher-researcher, at the head of this project with his colleague Hervé Trebaol.

We therefore had three objectives: to invent a wheel that was magnetic, cylindrical and deformable.

A juxtaposition of disks as a solution

“The main problem we encountered was being able to adapt to these cylindrical penstocks,” explains Yannick Argouarc’h. The wheels, as they exist, offer few points of contact on a support like this. We therefore had three objectives: to invent a wheel that was magnetic, cylindrical and deformable. What has been called self-adaptive on contact”.

Yannick Argouarc’h and Hervé Trebaol, mechanics teachers at the Ensta Bretagne engineering school, in front of a prototype magnetic wheel robot. (The Telegram / Rémy Quéméner)

Nearly three years of work, and at least one year of tests, are necessary to achieve a conclusive result. The two mechanics teachers imagine a system of juxtaposition of discs, forming the wheel, which adapts to the geometry of the support. The robot keeps the same contact on a flat surface or on a rounded plane. Very powerful magnets ensure adhesion with the metal surface. In the mountains, researchers and an EDF team are carrying out conclusive tests in a forced pipe, which validates the first intentions.

Adapt to all uneven terrain

In May 2022, the patent, co-owned by Ensta Bretagne and EDF, was issued. “We were satisfied with this first stage but we said to ourselves: ‘Couldn’t we transpose this invention to the earth wheel?’, remembers Hervé Trebaol. The applications could be numerous in civil engineering, forestry, the military, agriculture… In the same way as for the first project, through twin but non-magnetic wheels, the contact surface on the ground is increased. This can be useful to increase the contact patch of the vehicle on uneven terrain. We validated the mechanism on wheelbarrow wheels, by manufacturing our Saturn robot”.

A second patent is filed in 2022, this time the sole property of Ensta Bretagne. Trials will now begin in November to implement this innovation on tractor wheels. “Now, it’s up to manufacturers to seize it. This wheel could revolutionize professional off-road transport systems. The material is there, and the fields of application for industry are numerous”.

What is this revolutionary wheel invented by the Ensta engineering school in Brest?