Electrically Driven Microengineered Bioinspired Soft Robots

Abstract

To create life‐like movements, living muscle actuator technologies have borrowed inspiration from biomimetic concepts in developing bioinspired robots. Here, the development of a bioinspired soft robotics system, with integrated self‐actuating cardiac muscles on a hierarchically structured scaffold with flexible gold microelectrodes is reported. Inspired by the movement of living organisms, a batoid‐fish‐shaped substrate is designed and reported, which is composed of two micropatterned hydrogel layers. The first layer is a poly(ethylene glycol) hydrogel substrate, which provides a mechanically stable structure for the robot, followed by a layer of gelatin methacryloyl embedded with carbon nanotubes, which serves as a cell culture substrate, to create the actuation component for the soft body robot. In addition, flexible Au microelectrodes are embedded into the biomimetic scaffold, which not only enhance the mechanical integrity of the device, but also increase its electrical conductivity. After culturing and maturation of cardiomyocytes on the biomimetic scaffold, they show excellent myofiber organization and provide self‐actuating motions aligned with the direction of the contractile force of the cells. The Au microelectrodes placed below the cell layer further provide localized electrical stimulation and control of the beating behavior of the bioinspired soft robot.

Microfluidic Tissue Engineering and Bio‐Actuation

“…In 2018, a batoid‐fish‐shaped robot powered by cardiac muscle tissue was presented (Figure 3B). [ 319 ] The robot was based on a substrate composed of two micropatterned hydrogel layers to provide one mechanically stable structure and one actuation component. The actuation layer consisted of GelMA embedded with carbon nanotubes (CNTs) to culture cardiomyocytes.…”

CeFlowBot: A Biomimetic Flow‐Driven Microrobot that Navigates under Magneto‐Acoustic Fields

“…In order to deploy the microrobots in such remote environments, it is required to visualize these microrobots under medical imaging modalities such as US. Since the above-mentioned microrobots [25][26][27][28] comprise a single microbubble (size ≈10-100 μm), they are hard to visualize under commonly available US imaging systems (1)(2)(3)(4)(5)(6)(7)(8)(9)(10). In this regard, designs with arrays of multiple bubbles like CeFlowBot offer an overall larger footprint (i.e., 500 μm) despite having constituent bubbles of similar size.…”

“…Over the past decade, contactless actuation of microrobots has opened gateways for diverse applications that range from microfluidic technologies, targeted therapy, drug delivery, to microsurgery in remote environments. [ 1 ] Inspired by nature, many microrobots mimic motion of a myriad of biological organisms from large sea creatures (e.g., octopus, [ 2 ] stingray, [ 3 ] jellyfish, [ 4 ] eel [ 5 ] ), to microorganisms (e.g., sperm cell, [ 6 ] bacterium, [ 7 ] alga [ 8 ] ). Since most of the above‐described organisms are aquatic, their anatomical features precipitate biomimetic approaches to design new microrobots that imitate efficient swimming motion of such organisms.…”

“…Over the past decade, contactless actuation of microrobots has opened gateways for diverse applications that range from microfluidic technologies, targeted therapy, drug delivery, to microsurgery in remote environments. [1] Inspired by nature, many microrobots mimic motion of a myriad of biological organisms from large sea creatures (e.g., octopus, [2] stingray, [3] jellyfish, [4] eel [5] ), to microorganisms (e.g., sperm cell, [6] similar kind of body movements as bio-organisms makes their fabrication and actuation difficult. [4] In addition, the use of numerous fabrication tools for such multi-step processing also makes the synthesis of such microrobots expensive.…”

Hylozoic by Design: Converging Material and Biological Complexities for Cell‐Driven Living Materials with 4D Behaviors

“…As a result, materials may be modified or combined with more conductive agents in order to increase the responsiveness of contractile systems. [ 119a,184a,187,189 ] In one example, by incorporating aligned CNT microelectrode arrays into a PEG hydrogel layer coated with CNT‐containing GelMA and cardiac tissue, Shin et al. demonstrated both composite conductivity‐dependent activity, and controlled actuation with the embedded arrays.…”