The "ChrYsalis Pavilion," designed by architects Francisco González, José Real, and Álvaro López, creates a pathway aligned with the axis of the building in which it is located, covered by a double-curved surface with a framework of warped curves.
Two basic materials were used: 6 mm diameter galvanized steel rods and steel nodes of the same size, which orthogonally fix the rods. For its assembly, the digital precision of augmented reality was combined with the physical materiality of parametric architecture, developing a system applicable to any type of surface that follows the same generation method.
ChrYsalis Pavilion by Francisco González, José Real and Álvaro López. Photograph by Edu Espinosa Garate.
Project description by Francisco González, José Real y Álvaro López
Building castles in the air
This is the idea behind this work. It is the theme of the MUGAK Architecture Biennial, held in 2025 in the Basque Country (Spain).
The chrYsalis pavilion is the result of this quest: the desire to explore the process of making the intangible tangible.
It is a research for constructive lightness, the materialisation of an architecture that lies on the borderline between what is drawn and what is built. The search for a utopia.
The history of architecture is a sequence of transgressive gestures: stubborn attempts to build utopias.
Matter is inseparable from architecture.
The idea, weightless, inevitably faces weight.
Building in the air — building castles in the air — involves the challenge of turning the immaterial into matter, of giving body to the imagined.
Building is, in essence, drawing: tracing what we wish to dominate geometrically. But building in the air requires drawing in the air. Based on the geometric principle of Monge's surface, the project generates a path aligned with the axis of the nave where it is located, covered by a double-curvature surface discretised by a network of warped curves.
It is the result of previous research into the construction of free-form surfaces using simple construction systems. In this case, only two basic materials are used: 6 mm diameter steel rods and cylindrical steel joints, all of the same type, which allow the bars to be fixed orthogonally, following the same geometric principle of generation.
The development is based on a parametric system that can be applied to any type of surface that follows the same generation system.
Its assembly, location and layout are carried out using augmented reality technology, merging digital precision with physical matter in a single construction gesture.
The space chosen for the construction is the nave of the church of San Telmo Museum, a former Franciscan convent in the city of Donostia-San Sebastian (Spain), now the Anthropological Museum. The almost magical location allows for the visual superimposition of the lines that make up the pavilion with the ribs of the vaults that cover the nave.
The working group based on Fablab Donostia, led by Francisco Gonzalez Quintial, architect and professor at the School of Architecture of the University of the Basque Country, has worked on this pavilion as a demonstration of the use of Monge's surface as a valid geometric principle for the construction of complex shapes using robotic digital manufacturing systems, under the direction of José Real Cambas, architect. The application of augmented reality as a support system for manufacturing and assembly, led by Alvaro Lopez Rodriguez, architect, has proven to be a great help in handling this type of surface. The team is completed by students and the lab technician from the School of Architecture.
"Things are nothing but the envelope of the invisible."
Rainer Maria Rilke
