Honeycomb Actuators Inspired by the Unfolding of Ice Plant Seed Capsules.
Plant hydro-actuated systems provide a rich source of inspiration for designing autonomously morphing devices. One such example, the pentagonal ice plant seed capsule, achieves complex mechanical actuation which is critically dependent on its hierarchical organization. The functional core of this actuation system involves the controlled expansion of a highly swellable cellulosic layer, which is surrounded by a non-swellable honeycomb framework. In this work, we extract the design principles behind the unfolding of the ice plant seed capsules, and use two different approaches to develop autonomously deforming honeycomb devices as a proof of concept. By combining swelling experiments with analytical and finite element modelling, we elucidate the role of each design parameter on the actuation of the prototypes. Through these approaches, we demonstrate potential pathways to design/develop/construct autonomously morphing systems by tailoring and amplifying the initial material's response to external stimuli through simple geometric design of the system at two different length scales.
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.|Cluster of Excellence "Image Knowledge Gestaltung: an Interdisciplinary Laboratory", Humboldt University of Berlin, Berlin, Germany.
Lorenzo
L
Guiducci
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.|Cluster of Excellence "Image Knowledge Gestaltung: an Interdisciplinary Laboratory", Humboldt University of Berlin, Berlin, Germany.
Khashayar
K
Razghandi
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Luca
L
Bertinetti
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Sébastien
S
Turcaud
Institute for Building Materials (IfB), ETHZ, Zurich, Switzerland.|Applied Wood Materials Laboratory, Empa, Dübendorf, Switzerland.
Markus
M
Rüggeberg
Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, Massachusetts, United States of America.
James C
JC
Weaver
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Peter
P
Fratzl
Institute for Building Materials (IfB), ETHZ, Zurich, Switzerland.|Applied Wood Materials Laboratory, Empa, Dübendorf, Switzerland.
Ingo
I
Burgert
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
John W C
JW
Dunlop
D000465:Algorithms; D055595:Mechanical Phenomena; D035723:Mesembryanthemum / Q000502:physiology; D008962:Models, Theoretical; D011108:Polymers; D012639:Seeds / Q000033:anatomy & histology / Q000737:chemistry / Q000502:physiology
D011108:Polymers