[论文解读] Bees with attitude: the effect of gusts on flight dynamics

Timothy Jakobi, Dmitry Kolomenskiy+5 more|arXiv (Cornell University)|Feb 10, 2018

Insect and Arachnid Ecology and Behavior被引用 3

一句话总结

本研究通过自由飞行中的三维运动追踪，调查了大黄蜂对离散阵风的响应。蜜蜂采用被动瞬时机动随后进行主动恢复以稳定飞行，其表现因阵风方向而异——向下阵风造成最严重的扰动，需要最长的恢复时间。

ABSTRACT

Flight is a complicated task at small scales in part due to the ubiquitous unsteady air which contains it. Flying organisms deal with these difficulties using active and passive control mechanisms to steer their body motion. Body attitudes of flapping organisms are linked with their resultant flight trajectories and performance, yet little is understood about how discrete unsteady aerodynamic phenomena affect the interlaced dynamics of such systems. In this study, we examined freely flying bumblebees subject to a single discrete gust to emulate aerodynamic disturbances encountered in nature. Bumblebees are expert commanders of the aerial domain as they persistently forage within complex terrain elements. Physical obstacles such as flowers produce local effects representative of a typified gust which threatens the precise control of intricate maneuvers. By tracking the 3D dynamics of bees flying through gusts, we determined the sequences of motion that permit flight in three disturbance conditions. Bees repetitively executed a series of passive impulsive maneuvers followed by active recovery maneuvers. Impulsive motion was unique in each gust direction, maintaining control purely by passive manipulation of the body. Bees pitched up and slowed-down at the beginning of recovery in every disturbance, followed by corrective maneuvers which brought attitudes back to their original state. Bees were displaced the most by the sideward gust, displaying large lateral translations and roll deviations. Upward gusts were easier for bees to fly through, causing only minor flight changes and minimal recovery times. Downward gusts severely impaired the control response of bees, inflicting strong adverse forces which sharply upset trajectories. Bees used interesting control strategies when flying in each disturbance, offering new insights into insect-scale flapping flight and bio-inspired robotic systems.

研究动机与目标

• 理解小型拍打飞行如何受到诸如阵风等非定常气动干扰的影响。
• 分析大黄蜂在暴露于代表自然环境湍流的离散阵风时的飞行动力学。
• 识别蜜蜂在阵风暴露期间为维持稳定性和轨迹所采用的控制策略（被动与主动）。
• 量化不同阵风方向（向上、向下、侧向）在位移、滚转偏差和恢复时间方面的响应差异。

提出的方法

• 使用高速三维运动追踪记录自由飞行大黄蜂在受控阵风下的飞行动力学。
• 在三个不同方向施加单一离散阵风：向上、向下和侧向，以模拟自然气动干扰。
• 通过分析飞行轨迹、身体姿态（俯仰角、滚转角）和速度变化，识别瞬时和恢复机动。
• 基于运动学模式，将运动序列分类为被动瞬时响应和后续主动恢复阶段。
• 对三种阵风条件下的位移、滚转偏差和恢复时间进行统计分析。
• 利用数据推断控制策略，并评估被动与主动机制在稳定飞行方面的有效性。

实验结果

研究问题

• RQ1 大黄蜂在不同方向（向上、向下、侧向）的阵风下，其飞行稳定性和控制方式如何？
• RQ2 对阵风的被动瞬时机动具有何种特征，其如何促进飞行稳定？
• RQ3 恢复机动的持续时间和强度如何随阵风方向而变化？
• RQ4 身体姿态（俯仰角、滚转角）在蜜蜂维持轨迹方面发挥何种作用？
• RQ5 位移和滚转偏差的大小在三种阵风条件下如何变化？

主要发现

• 蜜蜂对所有类型的阵风均表现出一致的被动瞬时机动随后是主动恢复的序列。
• 向下阵风造成最严重的扰动，导致强烈的不利力和最长的恢复时间。
• 侧向阵风引起最大的侧向位移和显著的滚转偏差，表明对侧向稳定性构成最大挑战。
• 向上阵风仅引起微小的飞行变化和最短的恢复时间，表明蜜蜂最有效地应对向上扰动。
• 在所有条件下，蜜蜂在恢复初期均出现抬头和减速，表明存在一种共同的初始稳定策略。
• 本研究发现，仅靠被动身体调节即可启动稳定，而完整轨迹恢复则需要主动控制。