3D actuation of foam-core liquid metal droplets

Yue Chen; Xuanhan Chen; Zhenhong Zhu; Mingyuan Sun; Shen Li; Minfeng Gan; Shi-Yang Tang; Weihua Li; Shiwu Zhang; Lining Sun; Xiangpeng Li

doi:10.1039/d2sm01349e

3D actuation of foam-core liquid metal droplets

Soft Matter. 2023 Feb 15;19(7):1293-1299. doi: 10.1039/d2sm01349e.

Authors

Yue Chen¹, Xuanhan Chen¹, Zhenhong Zhu², Mingyuan Sun¹, Shen Li¹, Minfeng Gan³, Shi-Yang Tang⁴, Weihua Li⁵, Shiwu Zhang⁶, Lining Sun¹, Xiangpeng Li¹

Affiliations

¹ College of Mechanical and Electrical Engineering, Soochow University, Suzhou, 215000, China. licool@suda.edu.cn.
² Children's Hospital of Soochow University, Soochow University, Suzhou, 215000, China.
³ Department of Orthopedic, The First Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215000, China. ganminfeng@suda.edu.cn.
⁴ Department of Electronic, Electrical and Systems Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK. S.Tang@bham.ac.uk.
⁵ School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
⁶ CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230026, China.

PMID: 36524440
DOI: 10.1039/d2sm01349e

Abstract

Precise manipulation of liquid metal (LM) droplets possesses the potential to enable a wide range of applications in reconfigurable electronics, robotics, and microelectromechanical systems. Although a variety of methods have been explored to actuate LM droplets on a 2D plane, versatile 3D manipulation remains a challenge due to the difficulty in overcoming their heavy weight. Here, foam-core liquid metal (FCLM) droplets that can maintain the surface properties of LM while significantly reducing the density are developed, enabling 3D manipulation in an electrolyte. The FCLM droplet is fabricated by coating LM on the surface of a copper-grafted foam sphere. The actuation of the FCLM droplet is realized by electrically inducing Marangoni flow on the LM surface. Two motion modes of the FCLM droplet are observed and studied and the actuation performance is characterized. Multiple FCLM droplets can be readily controlled to form 3D structures, demonstrating their potential to be further developed to form collaborative robots for enabling wider applications.