164
N. Chari et al.
Additional Aspects of Surveillance
1.
Externally the bio-mimicked MAVs should resemble insects/birds/bats in its
appearance.
2.
The speed of MAV can be taken as 20–30 kmph (approximately 5.6 to 8.3 m/s).
3.
The altitude ‘h’ can be fixed with reference to that of the launch point (1 km).
4.
During the initial space trials/demonstration of navigation, the range ‘S’ of MAV
can be less (for reducing battery power).
5.
The main function of MAVs is to transmit the captured signals (audio/video)
from the area of surveillance to the launch point.
6.
Special attention is needed while considering the sounds generated by the MAV
during flapping so as to keep up with bio-mimicking acoustic levels.
Summary
Salient Features of Insect Flight forming the basis for Bio-Mimicking MAVs may
be summarized as follows:
1.
Species-specific aerodynamic parameters may help in the better selection of
bio-mimicking MAV models.
2.
Low mass: 2–10 gm maximum.
3.
Moderate wingbeat frequency (10–20 cps) with a higher wing area through
suitable scale up (~2:1) to match the requirement of the MAV.
4.
Low Re range of operation: 102–104.
5.
Resilin like elastic fulcrum (protein elastomere) at the wing base.
6.
Flexible flapping wings with full control over the wing movement to develop
lift and thrust. These wings are capable of undergoing elastic structural
deformations during flight while withstanding the wind loads.
7.
Low Wing Aspect Ratio: Typically 2–3.
8.
Low flight velocity: 20–30 km/h (5.7–8 m/s).
9.
Flow physics of small insect fliers with low Re is not fully understood hence
it needs further detailed study.
10.
Enough care has to be taken for incorporating features for takeoff and landing
capability. Unfortunately, these aspects are still in primitive experimental
stages.
11.
Wind tunnel tests and CFD studies are needed to for the successful experi-
mental design.
12.
A bio-mimicking MAV should be capable of hovering and circling in addition
to horizontal motion.
13.
Data bank on insect flight in the selected category (such as migratory fliers)
needs to be compiled and analysed for getting realistic results with the MAV
design.