ERICA 소재부품융합 첨단제조장비 혁신인재 교육연구단
Untethered small-scale robotsare mechanical objects capable of being wirelessly powered and propelled in fluid environments.
These tiny automata can be precisely controlled to locations where human access is restricted. Consequently, small-scale robots
can be widely applicable in different fields  Small-scale robots (or micro-nanoswimmers) are often designed differently from
their macro-sized counterparts for two reasons. First, while macro-sized robots typically use onboard batteries, micro-nanobots
use external energy due to the current technological restriction of battery miniaturization. Second, small-scale robotscreate a propulsive
force in response to external energy. Unlike macro-sized robots, small-scale robots swimming in a fluid by reciprocal motion show zero
net displacement since the drag force exerted on objects dominates over the inertial force at such small scales. To overcome this
challenge, small-scale robots employee unique swimming strategies similar to microorganisms in nature.
In this talk, we discuss how micro-sized living entities propel in fluids and apply their swimming strategies to small-scale robots.
In order to achieve the swimming strategies inspired by nature, four different small-scale robots are newly designed by controlling
their properties, such as geometry, material, physical, and chemical properties. [3-5] Furthermore, their propulsion mechanisms are
understood for efficient and controlled propulsion by fully characterizing their resultant locomotion in Newtonian fluids.
Fig. 1 Schematics of four different small-scale robots that will be presented in the talk.
 K. E. Peyer, L. Zhang, B. J. Nelson, "Bio-Inspired Magnetic Swimming Microrobots for Biomedical Applications", Nanoscale, Vol. 5, No. 4,pp. 1259-1272, 2013.
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 B. Jang et al., "Undulatory Locomotion of Magnetic Multilink Nanoswimmers", Nano Lett., Vol.15, No. 7, pp. 4829-4833, 2015.
 B. Jang et al., "Catalytic Locomotion of Core-Shell Nanowire Motors", ACS Nano, Vol. 10, No. 11, pp. 9983-9991, 2016
 B. Jang et al., "Multiwavelength Light-Responsive Au/B-Tio2 Janus Micromotors", ACS Nano. Vol. 11, No. 6, pp. 6146-6154, 2017