Anatomy of foils, how are IMOCA foils made? - by Boating Magazine

Discovery of the manufacture of foils for IMOCa with the meeting of Luc Talbourdet, manager of the company Avel Robotics which produces these foils in a fully robotized way.

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• Anatomy of foils, how are IMOCA foils made?

In the IMOCA gauge , foils made their appearance in 2014, creating this new generation of boats with Dali's mustaches. This year, the adjectives on these appendages have flourished as their sizes increase. We were interested in their manufacture. There are several manufacturers, but we went to Lorient to meet Avel Robotics, which manufactures them robotically.

It is Luc Talbourdet, former Chairman of the IMOCA gauge , who is in command of Avel Robotics, a UFO in shipbuilding . Maintenance at the height of technology.

Luc Talbourdet, how would you describe the foils?

Often times, I compare them to airplane wings, except they're in the water! These appendages create power and straightening torque (25.5 tonnes per meter static).

What is a foil made of?

The profile is made up of 5 parts:

• the central beam
• rectangular structural element
• on each side, there are foam block elements
• the leading and trailing edges are carbon

The rectangular central element is in carbon fiber of intermediate modulus to which is added the high modulus, but given the cost of the latter, this remains limited!

Why use robots to build a foil?

This technology has already existed for a long time in aviation, the advantage is that the robot deposits in the mold up to 8 strips of pre-impregnated fiber of 6 mm, therefore a maximum of 4.8 cm of fiber at each pass. This pose ensures surgical precision and facilitates the curvature in the bend of the foil for example. In addition, the robot compresses each strip which reduces the vacuum.

Another advantage of the robot is that there is no loss of information between designers and manufacturing (it's a digital channel), we can trace the exact movements of the robot! With our technology, we are opening up a new path in boating.

How long does it take to make a foil?

Foils are made in pairs, we usually need 5 months to build them. But it's different with each team. For Apivia , we just delivered the internal structure. For the Occitane, we have manufactured all of its foils. Finally with Arkéa Paprec, it is the V2 pair that we produced in partnership with Lorima. The robot would save time if the foils were one-design.

Avel Robotics has just invested in a new 6-axis robot, ideal for the manufacture of rudders for example. And as his son told him, "But how did you do it before?"