title: Structured light enables biomimetic swimming and versatile locomotion of photoresponsive soft microrobots.
abstract: Microorganisms move in challenging environments by periodic changes in body shape. In contrast, current artificial microrobots cannot actively deform, exhibiting at best passive bending under external fields. Here, by taking advantage of the wireless, scalable and spatiotemporally selective capabilities that light allows, we show that soft microrobots consisting of photoactive liquid-crystal elastomers can be driven by structured monochromatic light to perform sophisticated biomimetic motions. We realize continuum yet selectively addressable artificial microswimmers that generate travelling-wave motions to self-propel without external forces or torques, as well as microrobots capable of versatile locomotion behaviours on demand. Both theoretical predictions and experimental results confirm that multiple gaits, mimicking either symplectic or antiplectic metachrony of ciliate protozoa, can be achieved with single microswimmers. The principle of using structured light can be extended to other applications that require microscale actuation with sophisticated spatiotemporal coordination for advanced microrobotic technologies.
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.
authors.forename: Stefano
authors.identifier: 0000-0001-7284-0007
authors.initials: S
authors.lastname: Palagi
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Mark
authors.affiliation: Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Cambridge CB3 0WA, UK.
authors.forename: Shang Yik
authors.initials: SY
authors.lastname: Reigh
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Melde
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.|Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
authors.forename: Tian
authors.initials: T
authors.lastname: Qiu
authors.affiliation: European Laboratory for Non Linear Spectroscopy (LENS), University of Florence, 50019 Sesto Fiorentino, Italy.
authors.forename: Hao
authors.initials: H
authors.lastname: Zeng
authors.affiliation: European Laboratory for Non Linear Spectroscopy (LENS), University of Florence, 50019 Sesto Fiorentino, Italy.|CNR-INO, 50019 Sesto Fiorentino, Italy.
authors.forename: Camilla
authors.initials: C
authors.lastname: Parmeggiani
authors.affiliation: European Laboratory for Non Linear Spectroscopy (LENS), University of Florence, 50019 Sesto Fiorentino, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Martella
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.
authors.forename: Alberto
authors.initials: A
authors.lastname: Sanchez-Castillo
authors.affiliation: Institut für Physikalische Chemie, Universität Stuttgart, 70569 Stuttgart, Germany.
authors.forename: Nadia
authors.initials: N
authors.lastname: Kapernaum
authors.affiliation: Institut für Physikalische Chemie, Universität Stuttgart, 70569 Stuttgart, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Giesselmann
authors.affiliation: European Laboratory for Non Linear Spectroscopy (LENS), University of Florence, 50019 Sesto Fiorentino, Italy.
authors.forename: Diederik S
authors.initials: DS
authors.lastname: Wiersma
authors.affiliation: Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Cambridge CB3 0WA, UK.
authors.forename: Eric
authors.initials: E
authors.lastname: Lauga
authors.affiliation: Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany.|Institut für Physikalische Chemie, Universität Stuttgart, 70569 Stuttgart, Germany.
authors.forename: Peer
authors.initials: P
authors.lastname: Fischer
mesh_terms: D040761:Biomimetic Materials; D016798:Ciliophora; D012371:Robotics / Q000295:instrumentation / Q000379:methods; D013550:Swimming