Fig. 7. Soft magnetic artificial muscles.

a Optical images of the engineered artificial microswimmers (upper) and motion of a flexible helix through a curved conduit (lower)¹³⁰. Reproduced from ref. ¹³⁰ (2019, CC BY 4.0). b Ferromagnetic soft continuum robots and navigation through a tortuous path (upper) and 3D cerebrovascular phantom network (lower)¹³². Copyright 2019 by AAAS. Reprinted with permission. c Micro jellyfish-like swimmer showing the capability of selective transportation of large beads¹³⁸. Reproduced from ref. ¹³⁸ (2019, CC BY 4.0). d A flexible robot with programmable three-dimensional magnetization and motion. (scale bar: 4 mm)¹³⁹. Copyright 2019 by AAAS. Reprinted with permission. e Microscale origami bird with multiple shape-morphing modes (scale bars: 30 μm)¹⁴⁰. Copyright 2019 by Springer Nature. Reprinted with permission