The invention and its applications
The invention was initially aimed at the inspection of EDF penstocks by means of magnetic attraction robots. Adherence on metal walls had to be ensured irrespective of their inclination (even vertical) and curvature. The main problem to be solved was to ensure a sufficient contact area between the metal, in theory undeformable, wheel, and the uneven surface in order to maximize the magnetic attraction force. The wheel invented by the ENSTA Bretagne team is a magnetic, metal and deformable wheel, comprising a set of side-by-side discs that adapt to the geometry of the surface on which it runs.
In a second stage, the invention was adapted to other types of applications with twin, but not magnetic, wheels. The property of adapting to uneven surfaces improves the ability of professional machines to negotiate uneven terrain, protects the soil and reduces tire wear.
The invention could thus involve a number of land applications in difficult terrain such as heavy load transporters, public works machines, the mining industry, agriculture or the forestry industry.
"Wheel automatically adapting to the rolling surface"
Marion Floret, head of the UAV competence center at EDF DTG:
ENSTA Bretagne has remarkable know-how in the development of autonomous robotics solutions for industrial applications. The work carried out in cooperation with EDF allows us to better understand the advantages and limitations of these technologies. We hope that they will provide for better monitoring of hydroelectric facilities in the future.
EDF assigned a study project to ENSTA Bretagne engineering students: the development of a mechanical platform for a penstock inspection robot for hydroelectric plants. The students sketched out a few ideas and then engineers and teachers from the school continued the studies and developed a completely new concept of magnetic attraction wheels.
A patent application relating to two subjects was filed jointly by ENSTA Bretagne and EDF: a magnetic wheel (all metal surfaces) and a land wheel (all terrain). The patent application was then extended internationally.
The patent application was published.
Production of prototypes. ENSTA Bretagne has implemented the invention on several wheel systems: underwater robot for submerged metal superstructures, 8-wheel land robot, industrial castor wheel and an agricultural tractor.
The patent was issued.