Mahkam Nima, Ugurlu Musab C, Kalva Sandeep Kumar, Aghakhani Amirreza, Razansky Daniel, Sitti Metin
Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany.
Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, ETH Zurich, Zurich 8093, Switzerland.
Proc Natl Acad Sci U S A. 2025 Jan 28;122(4):e2417111122. doi: 10.1073/pnas.2417111122. Epub 2025 Jan 22.
The emerging new generation of small-scaled acoustic microrobots is poised to expedite the adoption of microrobotics in biomedical research. Recent designs of these microrobots have enabled intricate bioinspired motions, paving the way for their real-world applications. We present a multiorifice design of air-filled spherical microrobots that convert acoustic wave energy to efficient propulsion through a resonant encapsulated microbubble. These microrobots can swim boundary-free in three-dimensional (3D) space while switching between various frequency-dependent locomotion modes. We explore the locomotion dynamics of microrobots with diameters ranging from 10 μm to 100 μm, focusing on their boundary-free 3D swimming and multimodal locomotion in response to acoustic stimuli below 1 MHz. Further, we elucidate the dynamics of these microrobots, featuring a single multiorifice cavity, which contributes to complex acoustic streaming and facilitates swift, unrestricted movements. Finally, we demonstrate that incorporating microrobots with additional nickel and gold layers significantly enhances their steering and visibility in optoacoustic and ultrasound imaging, enabling the development of the next generation of microrobots in healthcare applications.
新一代小型声学微型机器人的出现，有望加速微型机器人在生物医学研究中的应用。这些微型机器人的最新设计实现了复杂的仿生运动，为其在现实世界中的应用铺平了道路。我们提出了一种充气球形微型机器人的多孔设计，该设计通过共振封装微泡将声波能量转化为高效推进力。这些微型机器人可以在三维（3D）空间中无边界游动，同时在各种频率相关的运动模式之间切换。我们研究了直径从10μm到100μm的微型机器人的运动动力学，重点关注它们在低于1MHz的声刺激下的无边界3D游动和多模态运动。此外，我们阐明了这些具有单个多孔腔的微型机器人的动力学，这有助于复杂的声流并促进快速、无限制的运动。最后，我们证明，在微型机器人上添加额外的镍和金层可显著增强其在光声和超声成像中的转向和可见性，从而推动医疗保健应用中下一代微型机器人的发展。
