EFRI C3 SoRo: Design Principles for Soft Robots Based on Boundary Constrained Granular Swarms

这个项目将开发框架，以了解建模，传感，控制，设计和制造一类新的软机器人。 大多数软机器人避开了传统机器人的刚性连杆，而采用柔性结构。 相比之下，在这项工作中设计的机器人有它的“柔软性”出现在一个灵活的膜包裹的颗粒材料之间的相互作用。这个概念最好通过考虑变形虫来形象化，变形虫的外膜松散地包裹着一组内部组件。 通过允许膜外围的组件成为活跃的“子机器人”，就像草履虫外围的纤毛一样，整个结构可以像边界约束的机器人群一样移动和变形。此外，为了操纵物体并对环境施加巨大的力，机器人还将具有独特的干扰能力。当颗粒紧密堆积，而不是相互流过（如罐中的咖啡渣），它们形成固体（如真空包装袋中的咖啡渣）时，就会发生堵塞。 与传统机器人相比，这项工作的结果可能会带来几个优势，包括更好地适应物体，与动物组织等其他软结构进行物理交互，以及在非结构化环境中移动。 这可能会影响几个国家的需求，包括提供与人类一起工作或与人类一起工作的固有安全机器人，以大大提高美国制造业的竞争力。该研究还包括一个全面的扩大参与计划，重点是雇用代表性不足的少数民族作为研究生研究助理，并通过本科生研究经验计划与代表性不足的少数民族进行外联。这是再加上社会推广，建立在PI的先前参与与芝加哥科学和工业博物馆。机器人在这里开发将是第一个扩展的概念，颗粒软机器人想象自己作为主动机器人。虽然类似于机器人群，但这类新的机器人的显著不同之处在于，该项目将是第一个研究子机器人集合如何与其环境进行物理交互的项目。为了使这成为可能，将创建新的建模技术以及传感和驱动算法。建模将考虑用于子机器人颗粒动力学建模的多体刚体动力学、用于子机器人连接建模的大变形连续介质力学、用于确保模型预测在物理上可行的约束以及用于将所有元素结合在一起的拉格朗日力学。感测和驱动算法将利用边界群的紧急智能来感测外部环境，并鲁棒地驱动不同的全局行为以响应这种分布式感测，而无需任何集中式规划。该项目通过融合来自多个不同学科的概念和研究人员来增强基础设施。在工程中，这包括动力学和控制，材料和结构力学，材料工程和正式设计理论。在物理学中，它包括软凝聚物质的领域，特别是干扰相变和“活性物质”动力学的概念。“这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

This project will develop the framework to understand the modeling, sensing, control, design, and fabrication of a new class of soft robots. Most soft robots eschew the rigid links of traditional robots in favor of compliant structures. In contrast, the robot designed in this work has its "softness" emerge from the interactions among granular material encased in a flexible membrane. The concept is best visualized by considering an amoeba, in which an outer membrane loosely encapsulates a set of internal components. By allowing components on the periphery of the membrane to be active "sub-robots," much like the cilia on the periphery of a paramecium, the overall structure can move and deform like a boundary-constrained robotic swarm. Moreover, to manipulate objects and exert large forces on the environment, the robot will also have the unique ability to jam. Jamming occurs when particles become packed so closely that instead of flowing past each other (like coffee grounds in a can) they form a solid (like coffee grounds in a vacuum-packed bag). The results of this work may offer several advantages over traditional robots, including the ability to better conform to objects, physically interact with other soft structures such as animal tissue, and locomote in unstructured environments. This could impact several national needs, including providing inherently safe robots that work with or alongside humans to greatly improve US manufacturing competitiveness. The research also includes a comprehensive broadening participation plan with an emphasis on hiring underrepresented minorities as graduate research assistants and outreach to underrepresented minorities through a Research Experiences for Undergraduates program. This is coupled with societal outreach that builds upon the PI's previous involvement with the Chicago Museum of Science and Industry.The robot developed here will be the first to expand upon the concept of granular soft robots by imagining the granules themselves as active robots. While similar to robotic swarms, this new class of robots differs significantly in that this project will be the first to examine how the aggregate of sub-robots physically interacts with its environment. To make this possible, novel modeling techniques will be created as well as sensing and actuation algorithms. Modeling will take into account both multi-body rigid dynamics for modeling the dynamics of sub-robot granules, large deformation continuum mechanics for modeling sub-robot connections, constraints to ensure the model predictions are physically viable, and Lagrangian mechanics to bring all the elements together. The sensing and actuation algorithms will exploit emergent intelligence of the boundary swarm to sense the external environment and robustly actuate distinct global behaviors in response to such distributed sensing without any centralized planning. The project enhances infrastructure through melding concepts and researchers from multiple disparate disciplines. In engineering, this includes dynamics and control, mechanics of materials and structures, materials engineering, and formal design theory. In physics, it encompasses areas of soft condensed matter, in particular the concepts of the jamming phase transition and the dynamics of "active matter."This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.