Collaborative Research: From Biology to Mechanism: Harnessing Compliance in Locomoting Systems

长期以来，发明家们一直怀着敬畏和羡慕的心情看待动物在各种环境中爬行、游泳和飞行的敏捷和优雅。然而，在工程系统中复制生物运动的多功能性，稳定性和效率的能力一直困扰着科学家和工程师。这个项目将确定运动的基本原则，重点是最基本的生物属性之一，遵守的作用。顺应性在生物运动中无处不在，从鱼的有弹性的肋状尾巴到昆虫的膜状翅膀，再到蛇的肌肉发达的身体，各种各样的生命形式都有顺应性的存在;当一个人转动门把手或拿起勺子时--这些任务对机器人系统来说是不平凡的--他们可以依靠手中的顺从性来被动地适应环境中的小干扰和不确定性。 这个项目旨在弥合刚体力学经典研究之间的差距，长期以来一直是机器人学科的范围，并符合生物运动策略。这项研究将合理化顺应策略和结构，出现在性质。 这些知识可以反过来被用来设计新的通用顺应机器，其中可能包括机器人系统中的运动和操纵的鲁棒策略和用于收集能量的新顺应机制。这项研究，这是在连续变形系统的控制和力学的交叉点，将开发两个新的数学方法来驯服与优化的顺应性系统的复杂性。 第一种方法源于几何力学，它在研究简单系统的运动中已经被证明是有效的。第二种方法通过首先用动态成本函数求解最佳运动学（例如，游泳者的最佳划水模式），然后反转最佳运动学以找到相关的动态参数（例如弯曲刚度）来反转优化问题。除了开发这两种新的数学工具外，该项目还将研究不同生物运动模式背景下合规性的作用。通过几十年的累积研究，科学界已经对依从性在孤立应用中的作用建立了合理的理解，例如腿走路和跑步，但相对而言，这个概念如何扩展到其他模式，如爬行，游泳和昆虫飞行。这项研究将通过调查激发这些系统的形式和生理学的基本物理原理来解决这个问题。 然而，最大的贡献将来自这些成果的融合。通过开发跨多种运动模式的新见解，该项目旨在将研究结果扩展到顺从性和运动的一般框架。然后，这个框架将作为工程师的出发点，他们可以在兼容设计方法的更大地图中扩展自己的系统。

Inventors have long viewed the agility and grace of animals that crawl, swim, and fly in all environments with awe and envy. However, the ability to replicate the versatility, stability, and efficiency of biological locomotion in engineered systems has eluded scientists and engineers alike. This project will identify fundamental principles of locomotion, with an emphasis on the role of one of the most fundamental biological attributes, compliance. Compliance is ubiquitous in biological locomotion, appearing in diverse forms of life from the elastic ribbed tail of a fish, to the membrane wings of an insect, to the sinewy muscular body of a snake; when a human turns a door knob or picks up a spoon -- tasks that are nontrivial for robotic systems -- they can rely on compliance in the hand to passively adjust to small disturbances and uncertainties in the environment. This project seeks to bridge the gap between classical studies in rigid body mechanics that have long been the purview of the discipline of robotics, and compliant biological strategies for locomotion. The research will rationalize compliant strategies and structures that appear in nature. This knowledge can in turn be used to design new classes of versatile compliant machines, which may include robust strategies for locomotion and manipulation in robotic systems and new compliant mechanisms for harvesting energy. This research, which lies at the intersection of controls and the mechanics of continuously deformable systems, will develop two new mathematical approaches to tame the complexity associated with optimization of compliant systems. The first takes its roots in geometric mechanics, which has already proven effective in the study of locomotion of simple systems. The second inverts the optimization problem by first solving for optimal kinematics (e.g. optimal stroke patterns for swimmers) with a dynamic cost function, and subsequently inverting the optimal kinematics to find the associated dynamic parameters (such as bending stiffness). In addition to the development of these two new mathematical tools, the project will investigate the role of compliance within the context of different biological locomotion modes. Through decades of cumulative research, the scientific community has established a reasonable understanding of the role of compliance in isolated applications, such as legged walking and running, but comparatively little is known in terms of how this concept extends to other modes such as crawling, swimming, and insect flight. This research will address the issue through investigations of the underlying physical principles that motivate the form and physiology of each of these systems. However, the greatest contribution will come through the amalgamation of these results. By developing new insights across multiple locomotion modes, this project aims to extend the findings into a generalized framework for compliance and locomotion. This framework will then serve as a jumping off point for engineers, who can situate their own systems within a greater map of compliant design methodologies.