Electro-mechanically guided growth and patterns

Abstract

Several experiments have demonstrated the existence of an electro-mechanical effect in many biological tissues and hydrogels, and its actual influence on growth, migration, and pattern formation. Here, to model these interactions and capture some growth phenomena found in Nature, we extend volume growth theory to account for an electro-elasticity coupling. Based on the multiplicative decomposition, we present a general analysis of isotropic growth and pattern formation of electro-elastic solids under external mechanical and electrical fields. As an example, we treat the case of a tubular structure to illustrate an electro-mechanically guided growth affected by axial strain and radial voltage. Our numerical results show that a high voltage can enhance the non-uniformity of the residual stress distribution and induce extensional buckling, while a low voltage can delay the onset of wrinkling shapes and can also generate more complex morphologies. Within a controllable range, axial tensile stretching shows the ability to stabilise the tube and help form more complex 3D patterns, while compressive stretching promotes instability. Both the applied voltage and external axial strain have a significant impact on guiding growth and pattern formation. Our modelling provides a basic tool for analysing the growth of electro-elastic materials, which can be useful for designing a pattern prescription strategy or growth self-assembly in Engineering.

Harnessing Gravity‐Induced Instability of Soft Materials: Mechanics and Application

“…Wrinkles as a ubiquitous phenomenon, have received considerable attention over the past 20 years. [63][64][65][66][67][68][69][70][71][72] Studies revealed that a sheet exposed to stretch or bending can induce compressive strain in somewhere of boundary layers, leading to the formation of wrinkles within the structure when a critical stress is reached. The understanding of this phenomenon has provided valuable insights into the mechanics and behavior of wrinkling, and broadened the application of wrinkles in surface property control and pattern formation.…”

Growth and morphogenesis of an everted tubular biological tissue

“…and growth gradient [37][38][39], initial residual stress and electric field [40][41][42][43], curvature and incompatibility [44][45][46][47][48] are investigated by a large group of researchers. However, the underlying physical mechanisms of the morphogenesis of everted tubular biological tissues remain elusive.…”