Our current highly increased demand in energy- and resource-efficient building construction calls for a new alliance of simplicity and performance in technology and operation of future building systems. The building envelope plays a major role in such needed improvements by enabling the use of efficient or even autarkic systems that minimize energy demand by e.g. reducing cooling requirements through efficient sun-shading. In the ADAPTEX R&D project weißensee school of art and design, Priedemann Facade-Lab, Fraunhofer IWU, Carl Stahl ARC, VERSEIDAG-INDUTEX, SGS and ITP jointly develop such a novel sun-shading system. By combining the potentials of textile light-weight construction and the smart material Shape Memory Alloy (SMA), significant reduction in material weight and operation energy for a shading system can be achieved.
SMA elements are generally very suitable for construction applications due to their performance free from wear and maintenance. They are activated by changes in temperature allowing an autarkic and adaptive reaction to external stimuli like ambient heat or solar radiation - complemented by decentralized control through electric current. The small size actuator induces force and movement and therefore is able to supersede complex motors and driving mechanisms. However SMAs are designed for the accuracy and standards of mechanical engineering rather than for architectural facade applications. ADAPTEX closes this gap by integrating SMA wire into large scale architectural surfaces using textile technologies. Implemented into soft surfaces SMA initiates changes in geometry thus adjusting parameters like transmission and reflection for shading and enhancing building performance.
The interdisciplinary project team of architecture, engineering, textile design and textile fabrication developed two concepts that will be introduced in the talk: ADAPTEX Mesh and Wave. ADAPTEX Wave is based on the interaction between a semi-rigid textile band and a SMA-wire. The textile band, with a wave-like geometry, is interwoven over its entire length with a linear SMA-wire. At high temperature, the SMA contracts and forces the textile strip to buckle. This leads to a closure of the overall surface. ADAPTEX Mesh consists of two identical layers of a structurally perforated textile arranged in front of each other. As the integrated SMA heats up, it contracts and causes one layer to slide upwards, reducing the overall permeability of the total surface in a smooth transition. As the temperature drops, the SMA releases its tension and the ADAPTEX surfaces return to their initial open state without further energetic input.
Full scale demonstrator testing for architectural application and parallel compiled simulation results are being used to evaluate the system performance as sun-shading elements and to compare these to state-of-the-art solutions. First results show the low to zero energy demand for operating the system while at the same time reducing the number of components used for adequate sun and glare protection. The system is currently further scaled up and optimized for various usage cases from indoor application to the context urban public spaces.
Close Up ADAPTEX Mesh (above) and Wave (below), ©weißensee kunsthochschule berlin, ADAPTEX