Damping by branching: a bioinspiration from trees

TL;DR

This paper introduces a bioinspired damping mechanism called damping-by-branching, which uses tree-like architecture to effectively reduce vibrations in slender structures, inspired by how trees withstand climatic forces with minimal damage.

Contribution

The study identifies and characterizes a new damping mechanism based on tree architecture, demonstrating its effectiveness through analytical, numerical, and realistic models.

Findings

Branching significantly enhances vibration damping in structures.

Approximately 30% of energy is dissipated per oscillation with the mechanism.

The damping mechanism is robust across different models.

Abstract

Man-made slender structures are known to be sensitive to high levels of vibration, due to their flexibility, which often cause irreversible damage. In nature, trees repeatedly endure large amplitudes of motion, mostly caused by strong climatic events, yet with minor or no damage in most cases. A new damping mechanism inspired by the architecture of trees is here identified and characterized in the simplest tree-like structure, a Y-shape branched structure. Through analytical and numerical analyses of a simple two-degree-of-freedom model, branching is shown to be the key ingredient in this protective mechanism that we call damping-by-branching. It originates in the geometrical nonlinearities so that it is specifically efficient to damp out large amplitudes of motion. A more realistic model, using flexible beam approximation, shows that the mechanism is robust. Finally, two bioinspired architectures are analyzed, showing significant levels of damping achieved via branching with typically 30% of the energy being dissipated in one oscillation. This concept of damping-by-branching is of simple practical use in the design of slender flexible structures.