Modular small-scale robots offer the potential for on-demand assembly and disassembly, enabling task-specific adaptation in dynamic and constrained environments. However, existing modular magnetic platforms often depend on workspace collisions for reconfiguration, employ bulky three-dimensional electromagnetic systems, and lack robust single-module control, which limits their applicability in biomedical settings. In this work, we present a modular magnetic millirobotic platform comprising three cube-shaped modules with embedded permanent magnets, each designed for a distinct functional role: a free module that supports self-assembly and reconfiguration, a fixed module that enables flip-and-walk locomotion, and a gripper module for cargo manipulation. Locomotion and reconfiguration are actuated by programmable combinations of time-varying two-dimensional uniform and gradient magnetic field inputs. Experiments demonstrate closed-loop navigation using real-time vision feedback and A* path planning, establishing robust single-module control capabilities. Beyond locomotion, the system achieves self-assembly, multimodal transformations, and disassembly at low field strengths. Chain-to-gripper transformations succeeded in 90% of trials, while chain-to-square transformations were less consistent, underscoring the role of module geometry in reconfiguration reliability. These results establish a versatile modular robotic platform capable of multimodal behavior and robust control, suggesting a promising pathway toward scalable and adaptive task execution in confined environments.

翻译：模块化小型机器人具备按需组装与拆卸的潜力，能够在动态受限环境中实现面向任务的适应性。然而，现有模块化磁控平台通常依赖工作空间碰撞实现重构，采用笨重的三维电磁系统，且缺乏稳健的单模块控制能力，这限制了其在生物医学场景中的应用。本研究提出一种模块化磁性毫米机器人平台，该平台由三个嵌入永磁体的立方体模块构成，每个模块设计用于特定功能角色：支持自组装与重构的自由模块、实现翻转行走运动的固定模块以及用于货物操作的抓取模块。运动与重构通过时变二维均匀磁场与梯度磁场的可编程组合驱动实现。实验通过实时视觉反馈与A*路径规划展示了闭环导航能力，验证了稳健的单模块控制性能。除运动外，该系统在低场强下实现了自组装、多模态形态转换及拆卸。链式到抓取形态的转换成功率达90%，而链式到方形转换的一致性较低，这凸显了模块几何结构对重构可靠性的影响。这些成果建立了一个具备多模态行为与稳健控制能力的通用模块化机器人平台，为在受限环境中实现可扩展的自适应任务执行提供了可行路径。