Liquid metal-based soft materials (hydrogels and elastomers) are capable of self-healing and restoring electrical functionality by magnetic field or even spontaneously, exhibiting uncompromising resilience to mechanical damage.[61-63] Here, Liquid metal soft robots can also be used to repair damaged microcircuits that occur at an unreachable space in a non-invasive manner. A maze was used to simulate an unreachable area, and multiple liquid metal-based soft robots are actuated towards the damaged section of the circuit. After reaching the damaged section of the circuit, the soft robots were fused and deformed by actuation with a bar magnet. Finally, the damaged section was successfully repaired (~6 min). A schematic illustration of such a process is shown in Figure S8. In Figure S8, the optical photographs of the movement (through the maze) and repairing process are shown, signifying the high control and potential of such soft robots. For instance, the soft robots can solve the maze and circumvent obstacles with ease without necessitating the use of an electric field and conductive electrolyte (compare with [64]).
Due to the fluidity of the liquid metal matrix, the liquid metal soft robot has a high degree of freedom of shape changeability, which endows it with the ability to adapt to the working environment, i.e., confined space. In channels with different widths, the liquid metal soft robot can adaptively change its shape and move in an optimized low-resistance mode. The self-adaptability of the shape enables the liquid metal soft robot to maintain good mobility in various environments.