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L. Parayitam et al.

h.

Ultra-Violet rays Sensing

Avian fliers use Ultra-Violet (UV) rays to detect the polarization pattern. Birds have

capability to recognize near Ultra Violet spectrum. Perception of UV rays by birds

is used for prey, food detection, signaling and communication. Most of birds like

eagle, hawk, and frugivorous birds etc. are using UV rays for prey.

i.

Odour/Smelling Sensory Method

It helps in detecting odour. It can be chemical or biological in its origin. Along

with vision, this helps in landing, take-off and searching for food and also for facili-

tating the search for mating (breeding). Moths, Salmon and pigeon are well studied

examples for animals which are using smell for orientation in their environment [12].

j.

Echo-location Techniques in Bats

Echo location in small bats is carried out by ultra-sonic waves ranging from 30,000

to 100,000 Hz. This is a unique evolutionary feature, which makes use of ultra-sonic

waves and ears during night. Oil birds are also using this method for navigation, but

basic/limited skills are used by the oilbirds.

k.

Sound Vibrations

Sound vibrations are detected by the ears and the final detection and analysis is

done by internal ear and the brain. Infra sound vibrations are used for long distance

migrants rather than short distances. Some birds like pigeons are sensitive to hearing

low frequency. They use infra sound vibrations for long distance travelling. Monarch

butterflies also use them for migration. Sea turtles appear to use infra sound and

acoustic waves for long distance travelling across ocean [14].

Many biological fliers, by making use of sense organs, prefer to migrate towards

tropical regions for warmth, food and for breeding. Photo periodism plays a signifi-

cant physiological role in the migration of insects, birds and mammals. The following

Table 13.1 will give the orientation and navigation methods used by the migrating

fliers, and this information is collected from various sources.

MEMS for MAV Navigation

MEMS is a technology and a methodology used in realizing micro-electronic and

mechanical devices. This technology also helps us to design and integrate various

components including MEMS for building a complex model or system. Further,

space and defense applications are considering the size and cost effective designs

for highly focused mission objectives. Most of the mission objectives are based on

the total weight of the components and systems developed. Thus, by using MEMS

technology, possibility of replacing the heavy and bulky components that are used

in space, communications and navigation is quite possible [13]. Not only replacing