The University of Stuttgart has developed FlectoLine, a cutting-edge façade system that reacts to its surroundings. Installed at the University of Freiburg’s Botanical Garden, the system transforms the exterior of buildings into dynamic, energy-efficient surfaces. This breakthrough offers new possibilities for architects, landscape designers, and product developers who are looking for sustainable and adaptable materials.

Nature as a Design Model

FlectoLine is based on biomimicry, taking cues from how nature moves. It mimics the snap-trap motion of the aquatic plant Aldrovanda vesiculosa and the folding of bug wings. These natural models inspired a system that bends without hinges, using flexible zones and built-in air chambers. As a result, the panels move smoothly and without complex mechanics.

Unlike traditional façades, which remain static, this system responds to light, temperature, and user needs. When air fills the cushion-like actuators, the modules bend in a set direction. Releasing the air causes them to return to their original shape. This movement is efficient, silent, and reliable.

Smart Materials and Solar Control

The panels use fibre-reinforced composite materials, built with zones of different stiffness. Two versions are available: one uses a mix of thermoset resins and elastomers, while the other uses thermoplastic layers. Both types are protected against weather, fire, and wind. Each one passed durability tests, proving it can last at least 15 years outdoors.

Thin-film organic photovoltaic (PV) cells are embedded in the panels. These cells capture solar energy and power the system. A digital twin—a virtual model of the façade—controls the system. It collects data from sensors measuring sunlight, temperature, wind, and indoor comfort. It then uses this data to adjust the panel positions for the best performance.

Designed for the Future

The FlectoLine system includes 101 modules, covering a total area of 83.5 square metres. Each panel can rotate up to 90 degrees using just 0.4 bar of pressure. This makes it highly efficient and low-maintenance.

Thanks to its smart design and durable materials, FlectoLine is ideal for both new buildings and renovations. It helps reduce energy use, improves comfort, and responds in real time to changes in weather and lighting. Most importantly, it shows how material science and design can work together to support a sustainable built environment.

Source & photos: ITKE/ITFT, University of Stuttgart