Flectofin: a hingeless flapping mechanism inspired by nature

• Published in: Bioinspiration & biomimetics 2011-12, Vol.6 (4), p.045001-1-7
• Main Authors: Lienhard, J, Schleicher, S, Poppinga, S, Masselter, T, Milwich, M, Speck, T, Knippers, J
• Format: Article
• Language: English
• Subjects: Actuation; Biomimetic Materials; Biomimetics; Computer Simulation; Computer-Aided Design; Construction Materials; Devices; Elastic deformation; Elastic Modulus - physiology; Equipment Design; Equipment Failure Analysis; Flapping; Glass fiber reinforced plastics; Interior Design and Furnishings - instrumentation; Kinematics; Models, Biological; Pollination - physiology; Polymers; Strelitziaceae - physiology
• ISSN: 1748-3190; 1748-3182; 1748-3190
• DOI: 10.1088/1748-3182/6/4/045001

This paper presents a novel biomimetic approach to the kinematics of deployable systems for architectural purposes. Elastic deformation of the entire structure replaces the need for local hinges. This change becomes possible by using fibre-reinforced polymers (FRP) such as glass fibre reinforced polymer (GFRP) that can combine high tensile strength with low bending stiffness, thus offering a large range of calibrated elastic deformations. The employment of elasticity within a structure facilitates not only the generation of complex geometries, but also takes the design space a step further by creating elastic kinetic structures, here referred to as pliable structures. In this paper, the authors give an insight into the abstraction strategies used to derive elastic kinetics from plants, which show a clear interrelation of form, actuation and kinematics. Thereby, the focus will be on form-finding and simulation methods which have been adopted to generate a biomimetic principle which is patented under the name Flectofin®. This bio inspired hingeless flapping device is inspired by the valvular pollination mechanism that was derived and abstracted from the kinematics found in the Bird-Of-Paradise flower (Strelitzia reginae, Strelitziaceae).