Inspired by the efficient swimming capabilities of swordfish, a novel wireless soft swordfish-like robot with programmable magnetization has been developed, integrating direct-ink-writing (DIW) 3D printing and assembly technology. This 20 mm long robot features a streamlined form and magnetically programmable movements, enabling biomimetic locomotion patterns such as straight-line swimming and turning swimming. The robot includes a silicone-based torso (body, abdomen, and pectoral fin) and a crescent-shaped tail fin made from a magnetically programmable polymer embedded with neodymium-iron-boron (NdFeB) particles. The tail fin, fabricated by multi-material alternating printing to achieve a gradient magnetism distribution, is controlled by an external magnetic field to mimic the rapid oscillation of a swordfish's tail, achieving a swimming speed of 0.51 BL/ s. The tail fin's asymmetric oscillation amplitudes, adjusted by magnetic field control, allow the robot to transition seamlessly from high-speed straight swimming to agile turning. The robot can perform tracking swimming along specific planned paths, such as “C” and “Z” shaped trajectories. Potential applications include environmental monitoring and targeted drug release. The multi-material 3D printing technology enhances the robot's efficiency and sensitivity in simulating natural biological movements, extending to the design and development of various flexible devices and soft robots.
Magnetoactive soft millirobots have made significant advances in programmable deformation, multimodal locomotion, and untethered manipulation in unreachable regions. However, the inherent limitations are manifested in the solid-phase millirobot as limited deformability and in the liquid-phase millirobot as low stiffness. Herein, we propose a ternary-state magnetoactive millirobot based on a phase transitional polymer embedded with magnetic nanoparticles. The millirobot can reversibly transit among the liquid, solid, and viscous-fluid phases through heating and cooling. The liquid-phase millirobot has elastic deformation and mobility for unimpeded navigation in a constrained space. The viscous-fluid phase millirobot shows irreversible deformation and large ductility. The solid-phase millirobot shows good shape stability and controllable locomotion. Moreover, the ternary-state magnetoactive millirobot can achieve prominent capabilities including stiffness change and shape reconfiguration through phase transition. The millirobot can perform potential functions of navigation in complex terrain, three-dimensional circuit connection, and simulated treatment in a stomach model. This magnetoactive millirobot may find new applications in flexible electronics and biomedicine.
危险品化学品经营许可证（带存储）