Role of outstretched forelegs of flying beetles revealed and demonstrated by remote leg stimulation in free flight

In flight, many insects fold their forelegs tightly close to the body, which naturally decreases drag or air resistance. However, flying beetles stretch out their forelegs for some reason. Why do they adopt this posture in flight? Here, we show the role of the stretched forelegs in flight of the bee...

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Bibliographic Details
Main Authors: Li, Yao, Cao, Feng, Vo Doan, Tat Thang, Sato, Hirotaka
Other Authors: School of Mechanical and Aerospace Engineering
Format: Journal Article
Language:English
Published: 2018
Subjects:
Online Access:https://hdl.handle.net/10356/87231
http://hdl.handle.net/10220/44350
Description
Summary:In flight, many insects fold their forelegs tightly close to the body, which naturally decreases drag or air resistance. However, flying beetles stretch out their forelegs for some reason. Why do they adopt this posture in flight? Here, we show the role of the stretched forelegs in flight of the beetle Mecynorrhina torquata. Using leg motion tracking and electromyography in flight, we found that the forelegs were voluntarily swung clockwise in yaw to induce counter-clockwise rotation of the body for turning left, and vice versa. Furthermore, we demonstrated remote control of left–right turnings in flight by swinging the forelegs via a remote electrical stimulator for the leg muscles. The results and demonstration reveal that the beetle’s forelegs play a supplemental role in directional steering during flight.