Self-Healing Small-Scale Swimmers

TL;DR

This paper introduces a novel self-healing mechanism for small-scale swimmers using magnetic microparticles, enabling rapid structural recovery and restored propulsion after severe damage, with high efficiency and minimal user input.

Contribution

It presents a new magnetic self-healing strategy for micro-swimmers that allows instant structural and functional recovery without external intervention.

Findings

Healing efficiency up to 88 percent.

Magnetic reorientation restores swimmer structure.

Modeling confirms magnetic force effectiveness.

Abstract

Herein, self-healing small-scale swimmers capable of autonomous propulsion and on-the-fly structural recovery are described. The new strategy instantaneously restores the functionality of the swimmer after it has suffered severe damage. Incorporation of magnetic microparticles in strips along with the printed functional body layers (consisting of conductive carbon, low-density hydrophobic polymer and catalytically active metal) results in rapid reorientation and reattachment of the moving damaged catalytic tail to its complimentary broken static body piece. Such magnetic alignment and attraction restores the original swimmer structure and propulsion behavior, independent of user input, displaying healing efficiencies as high as 88 percent. Modeling of the magnetic fields and simulations of various swimmer configurations are used to study the magnetic force field distribution around the swimmers. The influence of the damage position and pattern of multiple magnetic healing strips is examined and their influence upon healing efficiency is compared. Owing to its versatility, fast recovery, simplicity, and efficiency, the new on-the-fly self-healing strategy represents an important step towards the development of new classes of robots that can regain their functionality in situations of extreme mechanical damage where repair is not possible or challenging.