Bio-inspired compliant mechanisms for architectural design : transferring bending and folding principles of plant leaves to flexible kinetic structures

Abstract

This thesis lies at the intersection of architectural design, engineering, and biology. Inspired by flexible and robust structures found in nature, the research explores creative ideas that challenge our present understanding of mechanical constructions and offers an alternative to the prevailing paradigm of rigid-body mechanics. By exploring how the motion principles in flexible plant movements can be understood, abstracted, and transferred into novel design and fabrication processes; this thesis proposes innovative concepts that integrate hitherto neglected structural behaviors, such as bending and buckling. These behaviors are considered potential design drivers in the development of new kinetic structures.

The first section offers a comparison between Kinetic Structures in Design and Kinetic Structures in Biology. While at first glance these two areas may seem entirely unrelated, they share much in common. A particularly interesting connection is provided by compliant mechanisms where technical devices obtain their motion by the flexibility of their members and functionalize large elastic deformations. With these characteristics they are not that dissimilar to the motion principles found in plant leaves. The second section on Methodology is devoted to the transfer of knowledge between technology and biology. This section introduces the emerging science of biomimetics and generally discusses its working methods while also outlining its practical use for this research. In the third section of this thesis, a transdisciplinary framework is employed for a series of Case Studies. Here, seven exemplary plant movements are closely investigated and their underlying motion principles are recreated by means of modern computational simulation techniques. Based on these insights various bio-inspired compliant mechanisms are developed and transferred into adaptive facades shading systems. In the following section on Implementations, this technology is utilized for providing sun protection to doublecurved building facades and showcased on three conceptual projects.

The thesis concludes with a reflection on the Research Contributions and Future Outlook of this work and thereby invites the next generation of researchers and designers to build up on this work, keeping these newly created bonds between the disciplines alive.

Diese Forschungsarbeit liegt im Grenzbereich zwischen Architektur, Ingenieurwissenschaften und der Biologie. Inspiriert von flexiblen und widerstandsfähigen Strukturen in der Natur, werden kreative Ideen untersucht, die das übliche Konstruktionsverständnis, nämlich starre Bauteile mit Hilfe von Gelenken miteinander zu verbinden, durch neue Ansätze ablösen könnten. Im Mittelpunkt steht dabei die Untersuchung der Bewegungsmechanismen flexibler Pflanzen am Beispiel von Blüten und Blättern und deren möglicher Abstraktion und Nutzbarmachung für neue technikrelevante Design- und Fabrikationsprozesse. Hierzu werden Vorschläge entwickelt die gelenkfreie Biegung als Bewegungsmechanismus einzusetzen. Während das Prinzip der elastischen Verformung in der Technik noch kaum Beachtung findet oder sich nur als Versagensfall erwiesen hat, findet hier der Versuch statt, flexible Strukturen in der Architektur zu integrieren und beispielsweise als innovative Verschattungssysteme einzusetzen.