Liquid-Metal Magnetic Soft Robot With Reprogrammable Magnetization and Stiffness

Magneto-actuated soft robots have broad prospects for biomedical applications, such as cell manipulation, drug delivery, and noninvasive intervention. However, the single function and unchangeable stiffness restrict their practicality. Therefore, the work presented a functionally reconfigurable soft robot based on Gallium/NdFeB/PDMS composites. A heating-free reprogrammable magnetization technique was proposed to regulate the robot's response actions through re-patterning the magnetic domains. Moreover, a stiffness programming technique in terms of the liquid-metal thermotropic phase transition was employed to regulate the robot's stiffness. Four robot prototypes were constructed and tested. Experimental results showed that the robot performed variable responses and changeable stiffness, which satisfied different manipulation tasks. Therefore, the soft robot was endowed with variable functions and reusable characteristics. The proposed technique is expected to be applied to the batch manufacturing of intelligent soft machines.