Soft-robotic ciliated epidermis for reconfigurable coordinated fluid manipulation

Abstract

The fluid manipulation capabilities of current artificial cilia are severely handicapped by the inability to reconfigure near-surface flow on various static or dynamically deforming three-dimensional (3D) substrates. To overcome this challenge, we propose an electrically driven soft-robotic ciliated epidermis with multiple independently controlled polypyrrole bending actuators. The beating kinematics and the coordination of multiple actuators can be dynamically reconfigured to control the strength and direction of fluid transportation. We achieve fluid transportation along and perpendicular to the beating directions of the actuator arrays, and toward or away from the substrate. The ciliated epidermises are bendable and stretchable and can be deployed on various static or dynamically deforming 3D surfaces. They enable previously difficult to obtain fluid manipulation functionalities, such as transporting fluid in tubular structures or enhancing fluid transportation near dynamically bending and expanding surfaces.

Future bio-inspired robots require delicate structures

“…Replicating delicate structures of the biological system requires fabrication techniques that can handle multiple materials and generate delicate features at high resolution. This is imperative when integrating numerous micro/nano structures ( Wang et al, 2017 ), sensors ( Liu et al, 2022 ), and actuators ( Ren et al, 2022 ) to bio-inspired robotic systems at high spatial density. Recent progress in micro-assembly strategies ( Zhang et al, 2021 ) and 3D printing techniques ( Wehner et al, 2016 ; Truby et al, 2018 ) have demonstrated their capabilities in fabricating complex detailed features.…”

Concurrent Actuation and Sensing in Fluid by Cilia‐Like Transducers

“…As a start, we demonstrate several basic functions of the transducer. First, like other cilia-like actuators, [12,23] the current transducer is capable of manipulating flow fields to transport objects. Figure 1b illustrates the transport of a plastic bead through the collective beating of a four-transducer array (see Movie S1, Supporting Information).…”

“…[20] They have demonstrated their ability to drive miniature robots [21] and manipulate fluid and micro-objects. [12,22,23] These works have been well summarized and discussed in the recent critical review. [24] While cilia-like artificial devices on either sensing or actuation have gained fast developments, it is found that motile biological cilia, in fact, also carry out critical sensing functions.…”

“…[ 20 ] They have demonstrated their ability to drive miniature robots [ 21 ] and manipulate fluid and micro‐objects. [ 12,22,23 ] These works have been well summarized and discussed in the recent critical review. [ 24 ]…”

3D-printed micrometer-scale wireless magnetic cilia with metachronal programmability

“…Magnetic artificial cilia (MAC) use magnetic field as a wireless actuating stimulus (18)(19)(20). Comparing with artificial cilia driven by other stimuli (21)(22)(23)(24)(25), MAC can instantaneously respond to external magnetic fields and show robust controllability. Moreover, the magnetic actuation offers a safe interaction between the artificial cilia and the surrounding environment because no temperature increase or chemical changes are introduced.…”