Collaborative Magnetic Agents for 3D Microrobotic Grasping

Untethered microrobotic grasping has enabled the precise manipulation of small components in difficult‐to‐reach environments. However, the fabrication of deformable grasping robots at small scales requires advanced materials and fabrication technologies. Alternatively, multiple microrobots can be used to surround and grasp objects. By collaborating, microrobots can perform complex tasks that they would not be capable of executing individually. The complexity of controlling multiple untethered microrobots has limited the applications of collaborative microrobots to two‐dimensional operations. To fill this gap, this work proposes a collaborative microrobotic system for three‐dimensional grasping operations. The system is based on the control of two magnetic agents and the exploitation of the magnetic interactions between them to grasp, manipulate, and assemble passive components. A custom‐made closed‐loop controller is developed to automatically stabilize the system, achieving pose control of a grasped passive component (of 2 mm in size) with a precision of 300 μm in position and 10° in orientation. The main advantage of the proposed system is its capability to reconfigure the magnetic agents for other operations, as demonstrated by the assembly of a microgear and subsequent reconfiguration to power the assembled mechanism