38

P. Mukkavilli et al.

3.

Insects fly at low Reynolds numbers ranging from about 1 to 10,000 where

viscous effects, boundary layer flow separation and vortex formation are

predominant.

4.

Various lift generating mechanisms in insect flight include wake capture, passive

pitching mechanism, tip vortex formation, rapid pitching rotation, clap and fling

mechanism and LEV helping in the delayed stall.

5.

By virtue of wing and body movements, insects can prolong their pre-stall zone

ofoperationuptoanangleofattack,AOA,ofnearly90°.Thestallingangleforan

aeroplane wing, however, is limited to 15–20°. It may be relevant to mention that

the pre-stall period extends over an AOA of 40–75°, typically, helping in effec-

tive stall recovery through integrated sensory feedback mechanism resulting in

synchronous complex wing motion.

6.

The insect gets its lift basically from a powerful downward stroke, while the

upward stroke is more or less a recovery stroke with marginal or very little lift

generation.

7.

The wingbeat frequency of flying insects covering neurogenic (synchronous)

and myogenic (asynchronous) types are about 2 to 100 Hz for the former and

from 100 to 1000 Hz for the latter. If wings are mutilated, the ϑh increases in

the myogenic fliers.

8.

Many insects, because by virtue of their low mass and relatively large wing area,

try to float in the air (like a fish in the water) while flying.

9.

They are able to withstand the muscle fatigue from the continuous flapping of

wings through the presence of resilin, an elastomere protein at the wing base.

The actuator disc concept may be effective in calculating induced power in

hovering and may help in understanding the design for flapping wings of hovering

Insect mimicking MAVs.

References

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and Sons.

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3. Sane, S. P. (2003a). The aerodynamics of insect flight. The Journal of Experimental Biology,

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4. Sane, S. P. (2003b). Induced airflow in flying insects. The Journal of Experimental Biology,.209,

32–42.

5. Ellington, C. P. (1999). The novel aerodynamics of insect flight: Applications to micro-air

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6. Weis-Fogh, T. (1973). Quick estimates of flight fitness in hovering animals, including novel

mechanisms for lift production. Journal of Experimental Biology, 59(1), 169-230.

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parameters. Philosophical Transactions of the Royal Society. London, 13, 7–40.

8. Ellington, C. P. (1984b). The aerodynamics of hovering insect flight III. Kinematics.

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