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Bio-mimicking MAVs Based on Insect Flight Studies

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In the above process hovering needs more power than circling or horizontal level

flight. The power consumption during hovering is more than 10 times as compared

to other modes of flight.

Navigation Equipment for Bio-mimicking MAVs

a.

Artificial Horizon: It helps to maintain horizontal level flight and during

hovering it also helps to measure angle of attack or altitude angle (Fig. 12.2).

b.

Altitude Sensor: It helps the flying object to fly at a predetermined height ‘h’

above the ground level. These sensors play a vital role in avoiding the collision

of flight.

c.

Flight Direction Sensor: These sensors help the MAV to navigate with the help

of GPS systems available in the market. The launch point will be considered

as origin for the co-ordinate system in MAVs. However, the whole navigation

system works only during the availability of power supply. Otherwise MAV will

stop functioning and cannot navigate on its own unlike the other natural fliers.

d.

Control Systems: A relatively simple ‘Autopilot’ with On-Board-Computer

(OBC) to generate and implement control deflections as per the control law

(preferably derived from wind tunnel tests) with simplifying assumptions for

the lift equation.

For a given speed and altitude the lift equation is given by

Li f t = K1 a + K2δ

where K1 and K2 are constants.

a is the angle of attach (AOA).

δ is the wing tip depletion angle for control.

Fig. 12.2 MAV trajectory path during surveillance (conceptual)