Magnetic Soft Robot With the Triangular Head–Tail Morphology Inspired By Lateral Undulation

In this article, extend the uses of a deformable structure of magnetic elastomer to develop a bio-inspired locomotion system for millimeter-scaled robots. As proposed in other researches, this material allows a possibility of the motor-less mechanism powered by magnetic field. The actuating mechanism of the robot mainly relies on the body deformation due to magnetic alignment. On the other hand, herein, the magnetic soft robot with the triangular head-tail morphology and sine-based magnetization utilizes a high degree of freedom provided by magnetic compliance for mobility in a form of lateral undulation. Under the oscillating magnetic field, dynamic torque primarily acts to the head, the tail passively waves, and the whole body propagates a series of lateral body-waves for self-propulsion in fluid, instead of pushing out surrounding fluid to make a swimming gait. We achieve the independent control of the laterally undulating robot in force-free swimming, and demonstrate its tunable body deformation to swim in various diameters of the fluid-filled tubes. A by-product of the undulation can transfer a force rate to swim through the fabric-media. By the increase of the actuating frequency, the undulating robot propels faster to retain a stable swimming in the flow. The versatilities of the robot with the proposed mechanism can be applied to serve the diverse purposes as a reliable and effective locomotion system with a minimal control. Particularly in biomedical applications, miniature soft robots with a potential mechanism for self-propulsion can contribute the great results to pursue minimally invasive treatments.