Acoustic‐Magnetic 3D‐Printed Microrobots for Hybrid Manipulation in Viscous Oil Environment

ABSTRACT As a manipulation platform exhibiting distinct advantages at micro/nanoscales, microrobots demonstrate significant application potentials across biological, medical, and chemical engineering domains. However, current research for microrobot design and actuation predominantly focuses on aqueous and physiological fluid environments, and thus effective ways for driving microrobots to operate in viscous oil‐based media remains are still limited. To address this issue, we develop an acoustic magnetic hybrid microrobot leveraging bubble and fin structures for acoustic propulsion as well as magnetic coating layer for controlled navigation. With acoustic stimuli, the microrobot can achieve 2–6 mm/s motion speed propelled by the oscillating bubble. With magnetic steering, the microrobot can be controlled to move along arbitrary paths. Experimental results demonstrate that the microrobot can rapidly and accurately navigate to target locations in oil environments. Secondary acoustic radiation forces can capture target particles with different sizes, then transport them to target location and release. The proposed acoustic‐magnetic hybrid manipulation strategy enables microrobots to operate in viscous oil environments, offering a new paradigm to unlock the environment adaptability for complex application scenarios.