Figure 2. Controlled deformation of the liquid metal droplets.(a) Schematic illustration of the magnetic field-controlled elongation of the liquid metal droplet robot in water on an acrylic substrate. (b) Simulation result showing the magnetic field distribution of a bar magnet with the size of 5×1×0.5 cm3 (Side view). (c) Simulation result showing the magnetic field distribution of a bar magnet (5×1×0.5 cm3) at the distance of 4 mm and the distance of 2 mm (Top view). (d) Magnetic field-induced reversible elongation and deformation of a liquid metal soft robot upon manipulation of the magnetic field by the distance of a bar magnet. (e) Dependence of the magnetic field strength on the distance between the bar magnet and the sample. (f) Dependence of the length of a composite droplet on the magnetic field strength. The initial length and height were 6.8 mm and 1.6 mm, respectively. (g) Schematic illustration of the generation of a circular conductor via converging of a circular and permanent magnet to an LM composite on acrylic substrate, followed by rotating the magnet. (h) Simulation result showing the magnetic field distribution of a circular magnet (outer diameter is 3.5 cm, inner diameter is 1.5 cm, height is 0.5 cm) at the distance of 4 mm and the distance of 2 mm (Top view). (i) Simulation result showing the magnetic field distribution of a circular magnet (side view). (j) Optical photographs of the shape transformation of a composite puddle into a semi-circle and a circle, as shown schematically in (g).