CAREER: Flapping in the wind - passive mechanisms in insect wings for flight stabilization

职业：在风中拍动——昆虫翅膀中用于稳定飞行的被动机制

• 批准号: 0954381
• 负责人: Haoxiang Luo
• 金额: $ 40万
• 依托单位: Vanderbilt University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0954381&HistoricalAwards=false
• 关键词: CAREER; Flapping; wind; passive; mechanisms

0954381LuoMany insects such as flies, dragonflies, and butterflies impress us greatly with their amazing maneuvering skills. Dashing briskly in breezes, they possess such a freedom of locomotion which has long inspired us to imagine. The study of fluid dynamics involved in insect flight can not only help us unravel the scientific enigma behind the fascinating phenomena in nature, but also will transform design of autonomous micro air vehicles (MAVs). Many recent efforts have been devoted to understand the mechanisms of lift and thrust generation associated with insect wings and have achieved exciting progress. However, the degree of freedom of the insect body was typically excluded so that one could focus solely on the aerodynamics of the flapping wing. Therefore, some of the important physical phenomena associated with the interaction between the free flight and the wing-induced flow have been largely overlooked. One such example is the unique built-in mechanism that the flyers in nature utilize to stabilize their flight in the presence of disturbances and to achieve agility. Intellectual merits When combined with the body motion, the flapping movement of insect wings provides a counter drag and torque resisting the translational and rotational disturbances to the steady flight. In addition, the PI hypothesizes that the wing flexibility also provides a mechanism for disturbance rejection by attenuating the unsteady loads on the flapping flyers. Such passive flight stabilization features are drastically different from those in the conventional airplane design, and they can be easily disengaged by simply changing the wing kinematics to facilitate an active maneuver. The PI will apply accurate numerical simulations to study the unsteady flow behavior involved in these stabilizing mechanisms and also use an existing theoretical approach as a complementary tool to characterize the damping effect. The numerical approach is based on the efficient immersed-boundary solver developed at the PI's lab. The approach is able to handle complex/moving boundaries, capture detailed vortex structures in the flow, and address the three- dimensional flow-structure interaction. Novel stabilizing mechanisms for the flapping flight will be discovered and characterized through this research program. This research will open a new front for understanding the multiscale physics and active flight control of insects. The PI envisions that the results from this research will have a direct impact on the development of effective and efficient control strategies for biomimetic MAVs. Broader impacts The broader impacts come from extensive applications of the highly agile MAVs in the national defense, homeland security, and environmental safety. In addition, the com- putational approach developed in this research can be extended to study the flow physics associated with broader free-body locomotion problems in nature and that associated with flow-structure interaction in biological and biomedical systems, e.g., swimming fish, cardiovascular systems, and larynges. The research project will involve graduate students, undergraduate students, and under- represented groups. The research materials will be integrated into the courses that the PI teaches at Vanderbilt and will be taught with the innovative teaching strategies including interactive class- room activities, cooperative learning, and multiple assessment methods. K-12 students will be reached through incorporating high school students and their teachers in the research program. Hands-on workshops and web-based interactive tools will be designed to help K-12 students learn the science.

罗许多昆虫，如苍蝇、蜻蜓和蝴蝶，以其惊人的机动技巧给我们留下了深刻的印象。它们在微风中轻快地奔跑，拥有如此自由的运动，这一直激励着我们去想象。对昆虫飞行过程中流体动力学的研究，不仅可以帮助我们揭开自然界中迷人现象背后的科学之谜，而且将改变自主微型飞行器（MAVs）的设计。近年来，人们对昆虫翅膀产生升力和推力的机理进行了大量的研究，并取得了令人振奋的进展。然而，昆虫身体的自由度通常被排除在外，以便人们可以只关注扑翼的空气动力学。因此，与自由飞行和机翼诱导流之间的相互作用有关的一些重要物理现象在很大程度上被忽略了。一个这样的例子是独特的内置机制，在自然界中的传单利用稳定他们的飞行在干扰的存在，并实现敏捷。当与身体运动相结合时，昆虫翅膀的拍动运动提供了抵抗稳定飞行的平移和旋转干扰的反阻力和扭矩。此外，PI假设机翼的灵活性也提供了一个机制，通过衰减扑翼飞行器上的非定常载荷的干扰抑制。这种被动飞行稳定特性与传统飞机设计中的特性有很大的不同，它们可以通过简单地改变机翼运动学来方便主动机动而容易地脱离。PI将应用精确的数值模拟来研究这些稳定机制中涉及的非定常流动行为，并使用现有的理论方法作为补充工具来表征阻尼效应。数值方法基于PI实验室开发的高效浸入边界求解器。该方法能够处理复杂/移动的边界，捕捉流中的详细涡结构，并解决三维流-结构相互作用。通过这项研究计划，将发现和表征扑翼飞行的新稳定机制。该研究将为理解昆虫的多尺度物理和主动飞行控制开辟新的前沿。PI预计，这项研究的结果将对仿生MAV有效和高效控制策略的发展产生直接影响。更广泛的影响更广泛的影响来自于高度敏捷的MAV在国防、国土安全和环境安全方面的广泛应用。此外，本研究中开发的计算方法可以扩展到研究与自然界中更广泛的自由体运动问题相关的流动物理学以及与生物和生物医学系统中的流动-结构相互作用相关的流动物理学，例如，游泳的鱼，心血管系统和喉。这个研究计画将涉及研究生、本科生和代表性不足的团体.研究材料将被整合到PI在范德比尔特教授的课程中，并将采用创新的教学策略进行教学，包括互动课堂活动，合作学习和多种评估方法。K-12学生将通过将高中学生和他们的教师纳入研究计划来达到。实践研讨会和基于网络的互动工具将被设计来帮助K-12学生学习科学。