Self-Healing Actuators Inspired by Locomotion of Unicellular Organisms

Diverse locomotion mechanisms in nature enable organisms to navigate unfavorable environments, ensuring their survival and propagation. This study proposes the fabrication and characterization of a bio-inspired actuator based on the flagellar locomotion of single-celled organisms within the Eukarya domain. Subsequently, the design was refined for enhanced controllability and facile fabrication. The actuator leverages the eukaryotic locomotion principles while uniquely incorporating self-healing properties inspired by the cell wall structures of bacteria and eukarya. This actuator is fabricated from a composite hydrogel of gelatin, silk amino acids, glycerol, and deionized water and is a sustainable alternative to conventional silicone-based materials. The self-healing composite exhibited an elongation at break of 156.8 ± 5.7%; the bending angle of the assembled actuator recovered by approximately 58% after puncture and healing. This work provides the inspiration for novel robotic designs and propulsion systems with specialized functionalities, potentially expanding soft robotics’ operational boundaries.

Living organisms; Natural materials; Robotics; Self-healing component

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