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Bio-mimicking MAVs Based on Insect Flight Studies

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components due to the very small masses of insects and their flight components to

be replicated.

Choice of an Insect for Bio-mimicking

About seventy five thousand insects exist in nature. Considerable work has been

done on the Soap nut bug (T.javanica) in India by Chari [1] and his associates. The

geometry of T.j is useful and adaptable for designing a bio-mimicking MAV. Some

of the reasons to select T.j are listed below:

(a)

The body structure of T.j is more suitable for accommodating various internal

components to design MAVs.

(b)

Structurally its body is more rigid. The body contains only two parts i.e., an

upper spherical disc and a lower elongated disc. The lower disc can support

the internal components and the upper disc is just a cover, fitting over the

lower disc by a simple tongue and groove joint. Such discs for MAVs can be

easilymanufacturedbymouldingthetwoparts usingFibreReinforcedMaterial

Plastic (FRP) which can offer high structural rigidity.

(c)

Its body as viewed from top is of circular dish in shape (scutellum), which

offers less drag. The abdomen is more or less a truncated frustum and sternum

is one continuous boat like plate.

(d)

Complete thorax and part of the upper abdomen is covered by scutellum, which

is ideal aerodynamic device for reduced drag and enhanced fast air flow.

Salient Features of the Insect T.javanica and Its Adaptation

for MAV

The following suggestions are favorable for the adaptation of T.j model to design an

MAV:

• The insect geometry can be scaled up to 2 times for MAV design. The full-scale

width of body of the insect is 20 mm. Magnification is needed to a certain extent

to accommodate various internal components of MAV. The limitations in the

degree of feasible miniaturization of the internal components appear to dictate

the magnification factor.

• The diameter is estimated by the size of thorax and limited by the MAV sizes.

• The two pairs of wings of T.j on each side can be merged into one pair for the

practical MAV, for simplicity. They can have winglets to reduce the induced drag.

• Antennae (one pair) in the front (similar to those in the actual insect) for

transmission and reception of radio signals.

• The three pairs of legs of the insect can be replaced by a pair of brackets (one

vertical and the other horizontal, on the ground). The bottom bracket can act