Three-dimensional Micromechanics of Adhesion and Friction between Micro-pillar Arrays and Soft Gel Substrates

微柱阵列与软凝胶基底之间粘附和摩擦的三维微观力学

• 批准号: 1636203
• 负责人: Rong Long
• 金额: $ 36.61万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1636203&HistoricalAwards=false
• 关键词: Three; dimensional; Micromechanics; Adhesion; Friction

This award investigates the mechanics of how synthetic surfaces with micrometer-sized pillars adhere to and slide on soft and wet substrates. Micro-pillar arrays have been introduced on the wheel treads of robotic devices to improve their mobility on soft tissues, but the underlying mechanism is yet to be understood. Most existing theoretical models on the contact mechanics of micro-structured surfaces assume stiff substrates, and thus are not directly transferable to the case of soft substrates which can deform significantly during adhesive and frictional contact. Results of this research will improve the design of in vivo robotic devices for the next generation technology of non-invasive medical diagnosis and surgery. More broadly, new knowledge in soft material contact mechanics can also enable robotic handling of food, medical transplants and implants, thus benefiting the food and healthcare industries. Education and outreach programs will be developed to engage high school though graduate school students, exposing them to the fundamental concepts and exciting forefront of mechanics. Activities include course development, undergraduate student research program, and outreach lessons.A soft substrate can undergo large deformation upon contact with a micro-pillar array, which is three-dimensional in nature and inherently nonlinear. The large substrate deformation is expected to lead to a strong coupling between the normal and shear loadings of the micro-pillars, as well as between neighboring pillars. Understanding this coupling will facilitate the search for optimal pillar arrangement to achieve desired adhesion and friction properties. The PIs will develop a new experimental apparatus to achieve in situ mapping of the three-dimensional deformation fields in soft hydrogel substrates under contact, adhesion and friction. The soft gel substrate serves as a model material to simulate biological tissue or other soft and wet materials. The in situ deformation mapping capability will be combined with adhesion and friction tests and finite element modeling. The finite element model will connect the local micromechanics at the level of individual pillars to the global adhesion and friction, through an experimentally validated pillar-surface interface model. Results will offer new theoretical insights on the contact mechanics between micro pillar arrays and soft substrates, and enable high-fidelity simulations to drive the design of micro-pillar structures for optimized adhesion and friction on soft substrates.

该奖项调查了与微米大小的支柱合成表面如何粘附并滑动柔软和湿基底物的机制。在机器人设备的车轮胎面上引入了微柱阵列，以提高其在软组织上的迁移率，但是尚待了解基础机制。在微观结构表面的接触力学上，大多数现有的理论模型都假定刚性底物，因此无法直接转移到软底物的情况下，在粘合和摩擦接触过程中可能会显着变形。这项研究的结果将改善用于非侵入性医学诊断和手术的下一代技术的体内机器人设备的设计。 更广泛地说，软材料接触力学方面的新知识还可以实现对食品，医疗移植和植入物的机器人处理，从而使食品和医疗保健行业受益。 将开发教育和外展计划，以通过研究生毕业生吸引高中，使他们接触到基本的概念和令人兴奋的力学前沿。活动包括课程发展，本科生研究计划和外展课程。软底物在与微柱阵列接触后会发生大变形，该阵列本质上是三维的，本质上是非线性的。预计较大的底物变形将导致微柱的正常和剪切载荷之间以及相邻支柱之间的强耦合。了解这种耦合将有助于寻找最佳的支柱布置以实现所需的粘附和摩擦特性。 PI将开发出一种新的实验设备，以实现在接触，粘附和摩擦下软水凝胶底物中三维变形场的原位图。 软凝胶底物是模拟生物组织或其他软材料的模型材料。 原位变形映射能力将与粘附和摩擦测试和有限元建模相结合。有限元模型将通过经过实验验证的支柱表面界面模型将局部微力学的各个支柱水平连接到全局粘附和摩擦。 结果将提供有关微支柱阵列和软底物之间接触力学的新理论见解，并启用高保真模拟以驱动微柱结构的设计，以优化软底物上的粘附和摩擦。

项目成果

Mapping the nonlinear crack tip deformation field in soft elastomer with a particle tracking method

• DOI: 10.1016/j.jmps.2018.12.018
• 发表时间: 2019-04-01
• 期刊: JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
• 影响因子: 5.3
• 作者: Qi, Yuan;Zou, Zhanan;Long, Rong
• 通讯作者: Long, Rong

Patterned enteroscopy balloon design factors influence tissue anchoring

• DOI: 10.1016/j.jmbbm.2020.103966
• 发表时间: 2020-11-01
• 期刊: JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
• 影响因子: 3.9
• 作者: Bowen, Leah K.;Johannes, Karl;Rentschler, Mark E.
• 通讯作者: Rentschler, Mark E.

A representative volume element model for the adhesion between a micro-pillared surface and a compliant substrate

• DOI: 10.1016/j.mechmat.2018.01.004
• 发表时间: 2018-04-01
• 期刊: MECHANICS OF MATERIALS
• 影响因子: 3.9
• 作者: Kern, Madalyn D.;Long, Rong;Rentschler, Mark E.
• 通讯作者: Rentschler, Mark E.

Friction between a plane strain circular indenter and a thick poroelastic substrate

平面应变圆形压头与厚多孔弹性基材之间的摩擦

• DOI: 10.1016/j.mechmat.2019.103303
• 发表时间: 2020
• 期刊: Mechanics of Materials
• 影响因子: 3.9
• 作者: Qi, Yuan;Calahan, Kristin N.;Rentschler, Mark E.;Long, Rong
• 通讯作者: Long, Rong

Characterizing Adhesion between a Micropatterned Surface and a Soft Synthetic Tissue

表征微图案表面和软合成组织之间的粘附力

• DOI: 10.1021/acs.langmuir.6b03643
• 发表时间: 2017
• 期刊: Langmuir
• 影响因子: 3.9
• 作者: Kern, Madalyn D.;Qi, Yuan;Long, Rong;Rentschler, Mark E.
• 通讯作者: Rentschler, Mark E.