Slug-inspired Magnetic Soft Millirobot Fully Integrated with Triboelectric Nanogenerator for On-board Sensing and Self-powered Charging

Untethered bioinspired soft millirobots have significant advantages in the terms of good environmental adaptability, remote control and high locomotion efficiency, showing potential applications in various biomedical settings. However, to make the bio-inspired soft robot be a highly animal-like machine, more effective biofunctionalities should be integrated into the robot. Herein, inspired by Grey Field Slug, we develop a Sluginspired magnetic soft millirobot fully integrated with triboelectric nanogenerator (named Slug-inspired TENG-Robot) for on-board sensing and self-powered charging. Under untethered actuation of rotating magnetic field, TENG-Robot generates trains of pedal waves through periodic body fluctuations from the tail to head, producing a forward locomotion on the various terrains (e.g. plane, slope, gap, and tunnel). Synchronously, TENG-Robot harvests the self-transformation induced triboelectricity in closed contact-separation mode during this locomotion. TENG-Robot can self-detect the crawl process and self-power for charging the on-board capacitors via triboelectrification effect during the locomotion. Interestingly, Slug-inspired TENG-Robot integrated with various flexible circuits can light itself like firefly, charge the external electronic devices like electric eel, and response to high temperature stimulus like most animals. We believe the bio-inspired design strategies of TENG-Robot may pave important foundation to understand the principles underlying the behavior of animals and transfer them to the development of ever-more capable robots.