Figure 7.

(a) All kinds of locomotion of hydrogel water striders and common water striders, including freewill moving on the water surface and menisci climbing. Reproduced with permission [98]. Copyright 2021. The Authors, some rights reserved, exclusive licensee American Association for the Advancement of Science. (b) A microparticle carrier. The micro-worm could carry silica microspheres as cargoes and carrying the cargoes through other obstacle microspheres. i–iv: the optical images of the crawling motion of a hydrogel micro-worm in single cycle. Reproduced with permission [100]. Copyright 2020, ELSEVIER. (c) The steerable crawler navigated and manipulated 25 μm hydrogel cubes. (a,b): “U”-shaped crawler is steered by aiming the laser beam at spot (a) or (b) to turn right and left, respectively. The red arrow indicates the crawler trajectory (the scale bar corresponds to 100 μm). Reproduced with permission [101]. Copyright 2021, Mary Ann Liebert, Inc. (d) Transportation of tiny objects by the JMSR. Reproduced with permission [102]. Copyright 2021, American Chemical Society.