The four meter-long boat has a stiff steel fibre-reinforced concrete inner skeleton, covered by a two to three millimetre-thick waterproof concrete skin. The skeleton is designed using topology and shape optimization algorithms which reduce the material of a traditional canoe design and redistribute it in a skelleton-like structure in order to maximize the stiffness of the boat.
For the fabrication of this skeleton, a submillimetre thin plastic formwork was 3d printed and cast in ultra-high-performance fibre-reinforced concrete. The formwork for the entire boat weighed just over four kilogrammes and a precise, high-resolution surface texture, with details as small as half a millimetre, was transferred to the concrete skeleton to increase the contact area with the outer skin.
The construction process made possible a highly complex concrete skeleton with bones as thin as 15 millimetres in diameter which would be impossible to fabricate with any other digital fabrication technologies. 3D printing, a precious fabrication process, was used minimally, but had a significant impact on the overall design.