Magnetic Turtle-Like Robot with Biomimetic Movements Through Programmable Magnetic-Assisted 3D Printing

Animals can respond quickly to environmental stimuli and generate complex deformations. The locomotion modes of turtles vary with changing environments, which inspires the design of bionic robots. Existing turtle-like robots exhibit high movement efficiency and multi-terrain adaptability. However, challenges remain in improving the untethered designs, miniaturization, and response speed of these robots. Herein, a millimeter-scale turtle-like robot through programmable magnetic-assisted 3D printing is proposed. Hinge structures and magnetization distribution design are introduced to mimic the turtle joints. The magnetization distribution can be regulated through 3D printing. Considering that tortoises and sea turtles have different gaits, three magnetization distributions to achieve diagonal and synchronous gaits are designed. In the multi-terrain model, the robot exhibits maneuverability to crawl across sand, grass, gravel, and mountains. Specifically, the robot can climb over a stone wall that is 5.6 times its height and avoid obstacles. The robot is also capable of delivering cargo that weighs 1.2 times its weight along target trajectories. Furthermore, the different magnetization distribution designs enable robots to move separately within the same magnetic field. This independent actuation can be used for multi-robot collaboration.