fig2

Figure 2. Typical features of liquid metals that may serve to make endogenous magnetic fields. (A) Fluidic behavior. (B) Conductive electronic ink, reproduced with permission from Yang et al.^[28]. (C) Morphologically transformable machine, reproduced with permission from Sheng et al.^[29]. (D) Self-fueled motor, reproduced with permission from Zhang et al.^[30]. (E) Loadable by magnetic particles, reproduced with permission from Wang et al.^[31].