Speaker
Description
Biological systems provide a rich source of functional principles that can be translated into technical designs. In this work, a plant tendril is taken as an example to demonstrate how observation, interpretation, and abstraction can lead to a realizable mechanical concept.
Starting from the geometric and functional characteristics of tendrils, a segmented compliant structure was developed that captures the essential mechanism of coiling. The system consists of a flexible backbone with fixed overall length, actuated by a tendon running along the structure. Contraction of the tendon introduces a length mismatch between tendon and backbone, leading to controlled bending. The backbone is composed of rigid segments connected by compliant joints. An angular offset between these joints, in combination with tendon actuation, results in a three-dimensional spiral that reproduces the characteristic coiling behaviour observed in plant tendrils.
In this sense, the structure represents a simple example of a soft–hard interaction: deformation arises from the interplay between compliant materials and geometrically constrained elements. A qualitative mechanical description based on bending and tendon actuation is used to interpret the resulting deformation behaviour.
The concept was realized as a 3D-printed demonstrator using polymer-based materials, combining rigid segments with flexible joint elements. Actuation is controlled by a custom-built electronic system, enabling programmable tendon contraction. The resulting device is compact and suitable for demonstration, allowing direct visualization of the coiling mechanism.