Arthropod-Inspired Miniature Modular Vibration Direct-Drive Robot With Untethered Locomotion.

Miniature vibration direct-drive robots hold immense potential for missions in confined spaces, such as pipeline inspection and environmental detection. However, conventional fixed-configuration designs are restricted to single functionality, failing to adapt to the multifaceted demands of diverse operational tasks. Here, we present an arthropod-inspired untethered miniature modular vibration direct-drive robot, which achieves on-demand reconfiguration through standardized 19 mm × 32.5 mm × 18 mm driving units. Core innovations include tool-less nested locking interfaces for rapid assembly; compliant silicone connectors designed to mitigate vibration-induced wear and provide vibration isolation; chevron-shaped feet optimizing vibration-to-locomotion conversion; and a highly integrated onboard control architecture enabling untethered operation. The robot reconfigures into quadruped, hexapod, octopod, and circular morphologies with stable performance. In the quadruped robot (58.4 g; 46 mm × 75 mm × 38.8 mm), it reaches a maximum linear speed of 580.74 mm/s and rotational speed of 16.64 rad/s. The octopod robot sustains 450 mm/s under a 60 g payload while traversing 2.8 mm obstacles, 30 mm gullies, and confined pipelines. This work breaks fixed-configuration limitations, providing a generalizable paradigm for synergizing modularity and vibration-driven efficiency at the centimeter scale, offering new insights for miniature robots, and a versatile platform for confined-space operations.