TP 1: Bio-inspired programmable material systems
Principal Investigator: Thomas Speck
While interactive programmable material systems represent one of the major challenges in materials research, such material systems are widespread in biology. A good example is the group of lianas that has been investigated in the Plant Biomechanics Group for many years. While old liana stems are extremely flexible in bending and torsion and can thus passively follow the movements of their host trees, young liana axes are very rigid in bending and torsion and outperform tree branches of the same diameter by a factor of three to five. The reason for this is that the young axes, known as "searcher twigs", have to span the distance to a new host tree, which often amounts to several meters, in a self-supporting manner. The structural basis of this high bending and torsional stiffness is the extremely dense and mechanically extremely stiff wood of young liana axes. As soon as the searcher twigs have anchored themselves to a new host structure, the type of wood they built is "reprogrammed" and a structurally completely different, mechanically very flexible type of wood is formed. Material systems in the axes of lianas are excellent examples of highly adaptive (self-)programmable, interactive biological material systems, in which complex structural and mechanical changes occur interactively, triggered by various environmental stimuli (e.g. presence of a supporting host structure or not). They are excellent concept generators for the development of bio-inspired technically programmable and interactive materials systems.