Bio-inspired efficient pulsatile locomotion

PI：Leftwich，MeganProposal编号：1604876这项提案的重点是确定周期性移动鳍状肢的海洋动物使用的高性能游泳的机制。为了设计机器人原型，建议在华盛顿特区史密森国家动物园(SNZ)对海狮的运动进行真实的实验数据，并对这些游泳者的机动运动进行数学描述。然后，这些原型将被用于实验室环境中，对其周围的流动进行详细测量。这项研究的发现可以节省能源，因为在水下物体(例如，船只、潜艇、无人驾驶机器人)周围进行流量控制。要了解大型动物周围的流体动力学，必须首先描述其运动学特征。为这项工作提供信息的以前的努力没有包括对相关参数的定量描述，以便进行详细的、受控的水动力研究。此时，建议在华盛顿特区的SNZ进行一次全面的实地研究。这项研究将提供海狮动作的数字目录和详细的数学描述。这项研究最初将重点放在稳定的游泳行为(拍手)上，然后进行包括转身、加速和其他高级动作的研究。二维和三维数据都将使用三台同步数码相机获得。这需要对大型自由游泳体的无标记三维跟踪技术进行重大开发。虽然已经有了小范围运动(昆虫)或高度可预测的运动(人类行走)的方法，但这些工具不适用于轨迹未知的一般运动。一旦运动学数据就位，将在实验室环境中制造出一个流体力学安静的非定常推进器的复制品。虽然对游泳海狮的观测数据提供了对这种推进力的洞察，但了解其对周围环境的水动力效应是不够的。本文提出的工作将为设计和建造机器人海狮前鳍奠定基础。最后，推进表面的高倍率图像将使研究其自然流动控制能力成为可能。教育活动涉及研究生、本科生和高中生。此外，通过国家动物园之友(Fonz)计划，PI将参与SNZ的教育项目，包括讲座以及在加州海狮展览中创建教育展示和互动模块。最后，最近和正在进行的媒体对这项工作的兴趣提供了一个与公众就流体动力学进行对话的平台。

PI: Leftwich, MeganProposal Number: 1604876The focus of this proposal is to determine the mechanism for high-performance swimming that is used by sea animals that move their flippers in a periodic manner. It is proposed to take real life experimental data for the motion of sea lions at the Smithsonian National Zoological park (SNZ) in Washington, DC, and to mathematically describe the maneuvering motion of these swimmers in order to design robotic prototypes. These prototypes will then be used in a laboratory setting to take detailed measurements of the flow around them. Findings from this research could lead to energy savings because of flow control around submerged objects (e.g., ships, submarines, unmanned robotic vehicles). To understand the hydrodynamics around a large animal, one must first characterize its kinematics. Previous efforts to do so, which inform this work, do not include quantitative descriptions of the relevant parameters for a detailed, controlled hydrodynamic study. At this time, it is proposed to conduct a comprehensive field study at the SNZ in Washington, DC. This study will provide a digital catalog of sea lion maneuvers and a detailed mathematical description of them. The study will initially focus on steady swimming behavior (the "clap") before progressing to include turning, accelerating and other advanced maneuvers. Both two- and three-dimensional data will be obtained using three synchronized digital cameras. This required significant development of markerless three-dimensional tracking techniques for large free-swimming bodies. While methods exist for small-scale motion (insects) or highly predictable motions (human walking), these tools are not available for general locomotion with an unknown trajectory. Once the kinematic data are in place, a replicate will be crated that will be a hydrodynamically quiet unsteady propulsor in a laboratory setting. While observational data of swimming sea lions offer insight into such propulsion, it is not sufficient to understand its hydrodynamic effects on the surroundings. The work proposed here will lay the foundation for the design and construction of a robotic sea lion fore flipper. Finally, high-magnification images of the propulsive surface will allow the investigation of its natural flow control abilities. Educational initiatives involve graduate, undergraduate and high school students. In addition, through the Friends of the National Zoo (FONZ) program, the PI will participate in educational programs at the SNZ including lectures and the creation of educational displays and interactive modules within the California sea lion exhibit. Finally, recent and ongoing media interest in this work provides a platform for dialogs about fluid dynamics with the general public.