https://scholar.dgist.ac.kr/handle/20.500.11750/56594 2026-08-17T01:23:41Z https://scholar.dgist.ac.kr/handle/20.500.11750/60594 Title: Viola seed pod architecture shapes sequential, force-augmented pinching Author(s): Kim, Cheongsan; Won, Jihyun; Kim, Donghyeon; Jung, Sohyun; Kim, Ho-Young; Hyun, Youbong Abstract: Many plants explosively launch seeds, but these natural catapults often display inefficient, unpredictable energy transfer in seed ejection. Violets (Viola spp.) address this problem by ejecting seeds successively with consistent propulsive force from a single pod, a strategy that requires sophisticated energy release. In this work, we show that Viola achieves this feat with a simple and compact structure that generates adaptive force augmentation through sequential pinching. Our biological and mathematical analyses indicate that the pod valve's morphogeometry optimizes pinching with sufficient strength for seed ejection with limited material cost and creates a shifting force-amplifying hotspot, which allows consecutive seed ejections. We use this design principle to create autonomous zipping actuators for a range of applications, including biomedical soft machines. 2026-05-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60538 Title: Soil water harvest inspired by desert horned lizards, Phrynosoma platyrhinos Author(s): Lee, Seungjoo; Choi, Junhee; Kim, Wonseok; Jung, Sohyun; Kim, Sung Jae; Kim, Wonjung; Kim, Ho-Young Abstract: Desert environments pose severe water scarcity challenges, leading to unique adaptations among native fauna. Notably, many species of desert horned lizards utilize a dermal drinking method, employing integumental microchannels to draw water from raindrops and moist soils via capillary action. However, the exact mechanism by which they eventually move the water collected between their jaws into their mouths remains elusive. Our research investigates this critical step in the drinking of desert horned lizards, Phrynosoma platyrhinos, revealing that the lizards use characteristic rhythmic jaw movements to achieve effective water intake. Inspired by their distinct water harvesting techniques, we have engineered an artificial soil water harvesting system that mimics these natural capillary flows and jaw movements to achieve water collection from soil. This system incorporates porous media to simulate water transport from soil and employs parallel plates to emulate lizard jaw actions, successfully demonstrating effective water collection and purification through integrated ion-exchange materials. This multifunctional system not only addresses the urgent need for water in arid regions but also simultaneously ensures the collected water's purity, removing harmful contaminants like heavy metals. 2026-05-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/58290 Title: Bioinspired and biohybrid soft robots: Principles and emerging technologies Author(s): Chen, Zhengkun; Chen, Jiafan; Jung, Sohyun; Kim, Ho-Young; Lo Preti, Matteo; Laschi, Cecilia; Ren, Ziyu; Sitti, Metin; Full, Robert J.; Yang, Guang-Zhong Abstract: Soft robots have drawn increasing attention due to their inherent flexibility, deformability, and adaptability. The natural world, with its evolutionary refinement, presents the best source of inspiration for building soft robots. Creatures with sophisticated soft bodies and delicate mechanisms can be ideal biological models. This perspective focuses on bioinspired and biohybrid soft robots, providing a comprehensive review of the latest research in this area. We introduce the state-of-the-art principles of soft robots according to actuation, material selection, and sensing techniques. Based on biological classification methods used in nature, current research progress on biomimetic soft robots in animals, plants, and microorganisms is described. Emerging areas of interests are also highlighted for different biological species. Additionally, this paper explores the potential application areas of soft robots across various domains, outlining future challenges and ongoing developments. © 2025 2025-03-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/12950 Title: Avian mud nest architecture by self-secreted saliva Author(s): Jung, Yeonsu; Jung, Sohyun; Lee, Sang-im; Kim, Wonjung; Kim, Ho-Young Abstract: Mud nests built by swallows (Hirundinidae) and phoebes (Sayornis) are stable granular piles attached to cliffs, walls, or ceilings. Although these birds have been observed to mix saliva with incohesive mud granules, how such biopolymer solutions provide the nest with sufficient strength to support the weight of the residents as well as its own remains elusive. Here, we elucidate the mechanism of strong granular cohesion by the viscoelastic paste of bird saliva through a combination of theoretical analysis and experimental measurements in both natural and artificial nests. Our mathematical model considering the mechanics of mud nest construction allows us to explain the biological observation that all mud-nesting bird species should be lightweight. © 2021 National Academy of Sciences. All rights reserved. 2020-12-31T15:00:00Z