Extreme Mechanics Letters最新文献_第5页

Layer-jamming soft gripper for improved stiffness control and underwater adhesion 层卡软夹具，改善刚度控制和水下附着力

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-04-05 DOI: 10.1016/j.eml.2025.102322

Minseong Kim, Junyeock Oh, Donghoon Son

{"title":"Layer-jamming soft gripper for improved stiffness control and underwater adhesion","authors":"Minseong Kim, Junyeock Oh, Donghoon Son","doi":"10.1016/j.eml.2025.102322","DOIUrl":"10.1016/j.eml.2025.102322","url":null,"abstract":"<div><div>Soft robotic grippers have attracted significant attention due to their lightweight, simple structures, and versatile applications. Especially, soft suction cups (SSCs) are generally used for their low energy consumption and a high lifting ratio. However, they encounter challenges for mitigating a trade-off between conformability and adhesion performance and applications for the wet conditions. This paper introduces the layer-jamming soft gripper (LJSG), a novel design that significantly enhances adhesion while maintaining adaptive conformability and demonstrates effective underwater adhesion. Notably, the LJSG is resistant to hydraulic leakage due to a protective membrane attached to its body. Additionally, our design concurrently enhances adhesion capability with layer-jamming mechanism compared to conventional SSCs and mitigates the impact of unjammed layers on conformability by incorporating an interval to reduce required preload for interfacial adaptation. These features collectively enable the LJSG to demonstrate reliable performance in grasping diverse objects underwater. We elucidate the layer-jamming mechanism and demonstrate how jammed layers enhance maximum pull-off force by analytical method, numerical method, and experiments. The LJSG shows 300 % adhesion improvement than previous SSCs via the experiments, while 290 % from the analytical method and 245 % from the numerical method. The experiments also demonstrate that LJSG has an enhanced capability for gripping curved objects. This design can be applicable for grasping objects regardless of their curvatures and sizes. Hence, these findings underscore LJSG’s potential for diverse applications, particularly in challenging underwater environments, and position it as a viable solution for adaptive, high-performance soft robotic adhesion.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"77 ","pages":"Article 102322"},"PeriodicalIF":4.3,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143821299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Real-time generative design of diverse optimized structures with controllable structural complexities and high quality 多种优化结构的实时生成设计，结构复杂性可控，质量高

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-04-05 DOI: 10.1016/j.eml.2025.102321

Zongliang Du , Xinyu Ma , Wenyu Hao , Yuan Liang , Xiaoyu Zhang , Hongzhi Luo , Xu Guo

引用次数: 0

Brittle fracture of ultrathin gold nanosheets induced by local phase change and energy dissipation 局部相变和能量耗散诱发超薄金纳米片脆性断裂

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-04-04 DOI: 10.1016/j.eml.2025.102323

Jieun Park , Guh-Hwan Lim , Dayoung Yoo , Tae-Hoon Kim , Jong-Man Kim , Cheol-Woong Yang , Joonkyung Jang , Yoon Suk Choi , Byunkwon Lim , Jeffrey W. Kysar , Dongyun Lee

{"title":"Brittle fracture of ultrathin gold nanosheets induced by local phase change and energy dissipation","authors":"Jieun Park , Guh-Hwan Lim , Dayoung Yoo , Tae-Hoon Kim , Jong-Man Kim , Cheol-Woong Yang , Joonkyung Jang , Yoon Suk Choi , Byunkwon Lim , Jeffrey W. Kysar , Dongyun Lee","doi":"10.1016/j.eml.2025.102323","DOIUrl":"10.1016/j.eml.2025.102323","url":null,"abstract":"<div><div>Metals with a face-centered cubic (<em>fcc</em>) structure, such as gold (Au), are generally known for their excellent ductility. However, in this study, we observed a novel brittle fracture behavior in ultrathin Au nanosheets with a thickness of approximately 15 nm and a diagonal length of up to 80 μm, synthesized via an aqueous solution method. Nanoindentation experiments on these nanosheets revealed a unique fracture pattern, characterized by crack propagation at angles of 120° from the indentation point. Molecular dynamics (MD) simulations replicated this unusual behavior, attributing it to a localized phase transformation from the <em>fcc</em> to hexagonal close-packed (<em>hcp</em>) structure under external stress. We hypothesize that this phase transition is initiated by stacking faults introduced during the nanosheet fabrication process. The observed brittle fracture is further influenced by an energy dissipation mechanism, as evidenced by the formation of slip lines around the fracture site. Our findings suggest that even in ductile metals like Au, brittle fracture can occur due to localized phase changes and energy dissipation. This study provides new insights into the mechanical behavior of ultrathin Au nanosheets, with implications for their application in nanoelectronics and other advanced technologies.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"77 ","pages":"Article 102323"},"PeriodicalIF":4.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simple models of viscoelastic fibrillar adhesion to a rigid sphere 粘弹性纤维粘附于刚性球体的简单模型

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-28 DOI: 10.1016/j.eml.2025.102316

X.M. Liang , G.F. Wang , M. Ciavarella

{"title":"Simple models of viscoelastic fibrillar adhesion to a rigid sphere","authors":"X.M. Liang , G.F. Wang , M. Ciavarella","doi":"10.1016/j.eml.2025.102316","DOIUrl":"10.1016/j.eml.2025.102316","url":null,"abstract":"<div><div>The SPG (Schargott–Popov–Gorb) model of independent elastic fibrils in adhesive contact with a rigid sphere is a simple model of bioinspired adhesives, which with remarkable simplicity explains the preload dependence of pull-off and saturation when the compressive force is sufficiently high. However, typical materials of fibrils are viscoelastic, so we extend the model to consider viscoelastic behavior using a standard material model for each fibril. We use for the condition of nucleation of fibril detachment either the classical Schapery model or a more recent proposal by Shrimali and Lopez-Pamies. In either case, starting from a relaxed compressive contact, we find that the pull-off force also strongly depends on preload and is amplified by faster unloading rates, very differently for the two theories. A propagation theory follows for the Schapery model which seems to link the effective work of adhesion on contact retraction speed where the characteristic velocity has however nothing to do with the classical Schapery propagation theory, whereas the Shrimali and Lopez-Pamies model leads to detachment without a real prior phase of propagation. Some results are compared with those in the literature.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"77 ","pages":"Article 102316"},"PeriodicalIF":4.3,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Programming the energy landscape of 3D-printed Kresling origami via crease geometry and viscosity 通过折痕几何和粘度编程3d打印Kresling折纸的能量景观

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-27 DOI: 10.1016/j.eml.2025.102314

Samantha Mora , Nicola M. Pugno , Diego Misseroni

引用次数: 0

The effect of electro-momentum coupling on unidirectional zero reflection in layered generalized Willis Metamaterials 电动量耦合对层状广义Willis超材料中单向零反射的影响

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-27 DOI: 10.1016/j.eml.2025.102318

Hai D. Huynh , S.S. Nanthakumar , Harold S. Park , Timon Rabczuk , Xiaoying Zhuang

引用次数: 0

Multi-axed phase-transforming cellular material: A data-driven design and validation using finite-element method and machine learning 多轴相变细胞材料：使用有限元方法和机器学习的数据驱动设计和验证

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-26 DOI: 10.1016/j.eml.2025.102319

Masayuki Okugawa , Sosuke Kanegae , Yuichiro Koizumi

{"title":"Multi-axed phase-transforming cellular material: A data-driven design and validation using finite-element method and machine learning","authors":"Masayuki Okugawa , Sosuke Kanegae , Yuichiro Koizumi","doi":"10.1016/j.eml.2025.102319","DOIUrl":"10.1016/j.eml.2025.102319","url":null,"abstract":"<div><div>We developed the novel Atom-Mimetic Cube-Diagonally Multi-Axed Phase-Transforming Cellular Material (AMCDMA-PXCM), hereafter AM-PXCM for short, for a multi-axial bistable metamaterial designed with inspiration from a face-centered cubic (FCC) crystal structure: the designed AM-PXCM consists of spheres at atomic positions of structure and dogleg-shaped beams connecting nearest neighbor spheres. Stress-strain relationship of AM-PXCM was investigated by Finite Element Method (FEM) simulation. Analyzing the results by Logistic classification revealed that the mechanical properties significantly depend on the designing parameters and the distance between the beam and the tetrahedron (<em>k</em>) dominantly determines the bistability of the FCC-based AM-PXCM. In addition, combined with the machine learning method (i.e., inverse design), we succeeded to predict the designing parameters to have the desired mechanical properties for a bistable metamaterial. The designed AM-PXCMs were realized using a 3D printer and validified to show the predicted mechanical properties. This established method for developing AM-PXCM is suggested to be also applied to a development of an AM-PXCM with the symmetry of other crystal structures.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"77 ","pages":"Article 102319"},"PeriodicalIF":4.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Piezoelectric gauge transformation for inverse design of polar Willis transducers 极性Willis换能器反设计的压电表变换

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-22 DOI: 10.1016/j.eml.2025.102315

Li Huang , Rui Zhu , Gengkai Hu , Yangyang Chen

{"title":"Piezoelectric gauge transformation for inverse design of polar Willis transducers","authors":"Li Huang , Rui Zhu , Gengkai Hu , Yangyang Chen","doi":"10.1016/j.eml.2025.102315","DOIUrl":"10.1016/j.eml.2025.102315","url":null,"abstract":"<div><div>Piezoelectric lattices with delicately designed microscopic geometry are powerful building blocks to construct integrated sensors and actuators with versatile, yet unconventional, responses absent from bulk materials. However, the inverse design of the microscopic geometry to achieve a sought-after electromechanical response remains elusive. Here, we suggest an analytical approach, called <em>piezoelectric gauge transformation</em>, to design piezoelectric lattice transducers that can deform to an arbitrary desired displacement field when a voltage is applied. We first develop continuum piezoelectric gauge transformation and find that the transformed piezoelectric material displays piezoelectric polarity and Willis coupling in the sense that the applied electric field generates asymmetric stress and body force, and both rigid body rotation and translation induce electric charges. To design this polar and Willis-type piezoelectric material, we develop discrete piezoelectric gauge transformation and propose feasible lattice design guidelines. Numerical simulations are performed to validate the piezoelectric gauge transformation and demonstrate a range of appealing displacement control functions. The study presents a complete theoretical framework for the inverse design of lattice transducers to achieve arbitrary desired actuated displacement fields, beneficial to the development of soft actuators, robotics, and other piezoelectric devices.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"77 ","pages":"Article 102315"},"PeriodicalIF":4.3,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanical strength across metastatic lesions in trabecular bone: The interplay of microstructure and composition 骨小梁转移病灶的机械强度：微观结构和组成的相互作用

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-19 DOI: 10.1016/j.eml.2025.102317

Hanwen Fan , Hutomo Tanoto , Po-Ting Lin , Flordeliz Bowles , Shu Zhang , Zhonglin Liu , Feng Li , Eric O. Klineberg , Yuxiao Zhou

{"title":"Mechanical strength across metastatic lesions in trabecular bone: The interplay of microstructure and composition","authors":"Hanwen Fan , Hutomo Tanoto , Po-Ting Lin , Flordeliz Bowles , Shu Zhang , Zhonglin Liu , Feng Li , Eric O. Klineberg , Yuxiao Zhou","doi":"10.1016/j.eml.2025.102317","DOIUrl":"10.1016/j.eml.2025.102317","url":null,"abstract":"<div><div>Pathological bone fractures are a prevalent complication associated with metastatic cancer. However, the fragility associated with bone metastasis exhibits distinct characteristics that are not adequately addressed by current fracture risk assessment systems, which are primarily designed for osteoporosis. To understand how metastasis impairs trabecular bone strength, we experimentally measured mechanical strain across osteolytic and osteoblastic metastatic lesions under axial compression using mechanical testing coupled with micro-computed tomography (micro-CT) and digital volume correlation (DVC) method. We then attempted to evaluate the correlation between this mechanical strain and various parameters, including bone microstructure, bone mineral density, and bone fat-water concentration with the presence of trabecular bone, as assessed through high-resolution micro-CT and magnetic resonance imaging (MRI). This proof-of-concept study demonstrates a workflow that integrates mechanical testing and medical imaging data, enabling the potential to develop a quantitative correlation between local bone strength and the microstructural and compositional parameters measurable through medical imaging techniques. This innovative approach is helpful for identifying key factors influencing mechanical strength of metastatic bones and provides valuable insights for the development of new fracture risk assessment protocols for cancer patients.</div></div>","PeriodicalId":56247,"journal":{"name":"Extreme Mechanics Letters","volume":"76 ","pages":"Article 102317"},"PeriodicalIF":4.3,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143684644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Collision resistant study of spherical tensegrity structures for protective drone shells 无人机防护弹球形张拉整体结构抗碰撞研究

IF 4.3 3区工程技术

Extreme Mechanics Letters Pub Date : 2025-03-13 DOI: 10.1016/j.eml.2025.102312

Yaoyao Zhang , Kexin Zheng , Yi Zhao , Zhiyuan Zheng , Bingxing Chen , Muhao Chen

引用次数: 0