Thermoregulatory integration in hand prostheses and humanoid robots through blood vessel simulation

• Published in: NPG Asia materials 2024-07, Vol.16 (1), p.38-12, Article 38
• Main Authors: Jeong, Sang-Mi, Yang, Jonguk, Kang, Youngsoo, Seo, Hee Sung, Seo, Keumyoung, Lim, Taekyung, Ju, Sanghyun
• Format: Article
• Language: English
• Subjects: 639/166; 639/301/930/1032; Biomaterials; Blood circulation; Blood flow; Blood vessels; Chemistry and Materials Science; Circulatory system; End effectors; Energy Systems; Fibers; Hands; Heat; Humanoid; Infrared cameras; Infrared imagery; Infrared signatures; Materials Science; Optical and Electronic Materials; Prostheses; Robot control; Robotics; Skin; Structural Materials; Surface and Interface Science; Temperature control; Temperature distribution; Thermal simulation; Thin Films; Water circulation
• ISSN: 1884-4057; 1884-4049; 1884-4057
• DOI: 10.1038/s41427-024-00558-4

In this paper, we introduce an innovative approach for generating robotic faces with a thermal signature similar to that of humans and equipping prosthetic or robotic hands with a lifelike temperature distribution. This approach enhances their detection via infrared cameras and promotes more natural interactions between humans and robots. This method integrates a temperature regulation system into artificial skin, drawing inspiration from the human body’s natural temperature control via blood flow. Central to this technique is a fiber network simulating blood vessels within the artificial skin. Water flows through these fibers under specific temperature and flow conditions, forming a controlled heat release system. The heat emission can be adjusted by changing the dilation of these fibers, primarily by modulating the frequency of circulation. Our findings indicate that this approach can replicate the varied thermal characteristics of different human faces and hand areas. Consequently, the robotic faces appear more human-like in infrared images, aiding their identification by infrared cameras. At the same time, the prosthetic hands achieve a more natural temperature, reducing the discomfort typically felt in direct contact with synthetic limbs. The aim of this study was to address the challenges faced by the users of prosthetic hands. The results from this study show a promising direction in humanoid robotics, fostering improved tactile interactions and redefining human–robot relationships. This innovative technique facilitates further advancements, blurring the lines between artificial aids and natural biological systems. Robotic faces and hands with human-like thermal infrared emission and physiological temperature are achieved by replicating the circulatory system’s inherent temperature regulation mechanism. The keystone of our development is an intricate system of fibers, reminiscent of blood vessels, embedded within the artificial skin. The fiber network enables controlled heat dissipation by regulating water circulation to mimic human thermal signatures.