Abstract: Researching the cooperative operation and functional expansion of multiple minirobot assemblies has the potential to bring about significant advancements in the practical applications of minirobots. In this study, we present a novel assembly system comprised of arc-shaped NdFeB magnetic minirobots. These minirobots can be individually utilized as assembly units, allowing for function expansion and comprehensive capability enhancement. We fabricate four Semicircular Arc Magnetic Minirobots (SAMM) arranged in different configurations and analyze their force and motion characteristics. Furthermore, by using this unit as a base, various expansion structures such as latches, petals, and rings can be assembled through reasonable combinations. We define the comprehensive reinforcement interval by comparatively analyzing changes in the unit’s motion characteristics and operational capabilities. Precise motion manipulation is employed to verify the rationality of the basic unit structure and the feasibility of the assembly scheme. Our proposed self-assembly scheme for magnetic minirobots exhibits great potential and may be used as a paradigm for future research on expanding the functionality of minirobots.

Key words: NdFeB , · Semicircular arc , · Cutoff frequency , · Assembly , · Cooperative work , · Magnetic minirobots