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Development of Biomimetic-based High-output...

Date 2022.05.06. Writer 권세진 Hits 2646

Dongguk University Research Team led by Professor Changsun Choi
Development of Biomimetic-based High-output Hydro-actuator

 

From left to right:
Changsun Choi, Professor at the Department of Convergence Energy and New Material Engineering; Wonkyung Son, Researcher; Jaemyeong Lee, Researcher

○ The research team led by Changsun Choi, Professor at the Department of Convergence Energy and New Material Engineering, Dongguk University, Seoul, South Korea (corresponding author), and Sungwu Cheon, Professor at the Department of Electronics and Information Engineering at Korea University, Seoul, South Korea (co-corresponding author), was successful in overcoming the limitations of a conventional hydro-actuator by developing a high-output, high-power hydro-actuator with a fast electrothermal recovery capability.

○ A Geraniaceae plant is usually straight and long, but it twists itself and becomes spring-like when exposed to a dry environment. When it is twisted to the maximum extent, it bounces out to spread its seeds. Under rainy conditions, contact with a rain droplet causes it to spin and dig into the ground like a drill. Professor Choi’s research team studied the moisture-triggered spinning mechanics of such a plant to develop a fiber-type hydro-actuator.

○ An actuator is a switch or a motor device that switches its physical state according to electrical signal changes. A fiber-type hydro-actuator that uses water from its surroundings as a source of stimulant is highly usable in various fields, such as soft robotics, because of its silk-like soft characteristics. However, existing hydro-actuators have low output values and require long operational time owing to their substantially slow recovery processes that contrast with their sensitive reactions.

○ To solve this, the research team took inspiration from the moisture-activated self-twisting characteristic of a stork’s bill plant and designed an actuator with a fast electrothermal recovery. This newly developed actuator based on a carbon nanotube fiber featuring both high water reactivity and an electrothermal property demonstrated 120 times (143.8 W/kg) greater ultrahigh power density at an applied voltage of 5 V and at an operating speed that is 15 times greater than that of conventional hydro-actuators. It also showed no performance degradation, even at a very high internal temperature (102°C), through repeated cycle testing. Thus, it exhibited outstanding mechanical and thermal durability.

○ Professor Choi states, “The significance of this research is the development of a high-performance hydro-actuator using the excellent electrothermal characteristics of a carbon nanotube treated to exhibit sensitive moisture reactivity.” He showed anticipation by continuing to state, “This newly developed electrothermal-recovering hydro-actuator is very powerful and has high operational speed, which makes it ideal to be utilized in the converging field of the biomedical industry and for applications `in artificial muscles, smart fabrics, prosthetics, and artificial fingers.”

○ For this research, various groups of personnel participated, including (but not limited to) Wonkyung Son, researcher (first author), Shihyeong Kim, Ph.D. (Korea Institute of Industrial Technology), Sungbeom Jo, Ph.D. (Korea Institute of Ceramic Engineering and Technology), and Dongseok Seo, Professor (Sungkyunkwan University). The research result was published online in March 2022 in Nano Letters (IF = 11.189), a journal of nanoscience technology, under the title <high-power biomimetic="" carbon="" coiled="" electrothermal="" fabricated="" fast="" from="" hydro-actuators="" nanotube="" recovery="" with="" yarns="">.
(URL:https://pubs.acs.org/doi/10.1021/acs.nanolett.2c00250)</high-power>