Natures wonders: dragonfly flight controls (Introduction)

by David Turell , Thursday, May 26, 2022, 17:12 (910 days ago) @ David Turell
edited by David Turell, Thursday, May 26, 2022, 17:17

Carefully studied:

https://www.sciencedaily.com/releases/2022/05/220513113228.htm

"Researchers have untangled the intricate physics and neural controls that enable dragonflies to right themselves while they're falling.

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"The research reveals a chain of mechanisms that begins with the dragonfly's eyes -- all five of them -- and continues through its muscles and wing pitch.

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"'When we looked at their flight behavior, we were simultaneously in awe and frustrated," she said. "The trajectories are complex and unpredictable. Dragonflies constantly make maneuvers, without following any obvious direction. It's mysterious."

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"Wang realized that, unlike humans who have an inertial sense, dragonflies could rely on their two visual systems -- a pair of large compound eyes, and three simple eyes called ocelli -- to gauge their uprightness.

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"'These experiments suggest that vision is the first and dominant pathway to initiate the dragonfly's righting reflex," Wang said.

"That visual cue triggers a series of reflexes that sends neural signals to the dragonfly's four wings, which are driven by a set of direct muscles that modulate the left-wing and right-wing pitch asymmetry accordingly. With three or four wing strokes, a tumbling dragonfly can roll 180 degrees and resume flying right-side up. The entire process takes about 200 milliseconds.

"'What was difficult was figuring out the key control strategy from the experimental data," Wang said. "It took us a very long time to understand the mechanism by which a small amount of pitch asymmetry can lead to the observed rotation. The key asymmetry is hidden among many other changes."

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"'Flight control on the timescale of tens or hundreds of milliseconds is difficult to engineer," Wang said. "Small flapping machines now can take off and turn, but still have trouble remaining in the air. When they tilt, it is hard to correct. One of the things that animals have to do is precisely solve these kinds of problems.'" (my bold)

Comment: the bold emphasized the issue. How did this organism evolve with such intricate flight controls for a strange elongated body shape. Only design fits. And to prepare for the usual dhw complaint, dragonflies have many important functions in their ecosystem.

https://www.biophiliafoundation.org/dragonflies-environmental-indicators/

"Dragonflies -The Hawks of the Insect World Are Important Environmental Indicators
Dragonflies are an ancient family of insects. They have been around for 300 million years — predating even the dinosaurs. Some ancient dragonflies had a wingspan of more than 2 feet. Today, there are more than 5,000"

"...different species of dragonflies and they can be found on every continent except Antarctica. Conserving dragonflies and their habitat must be a priority because they are valuable environmental indicators. Biophilia Foundation is proud of its partners’ work to restore and protect dragonfly habitat."