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Navigation—A General Overview

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landing, takeoff and avoid obstacles. Barrows et al. [2], have discussed perception of

depth and optical flow. Optical flow helps in visual navigation in detecting horizon.

Insect ocelli give a simple system of optical flow detection [3].

As compared to the navigation methods used by biological fliers, many types of

artificial navigation systems are available in man-made fliers such as aero-planes,

missiles, ships, submarines and surface transport systems. However, complex biolog-

ical feedback systems with sense organs and brain in natural fliers and other migra-

tory animals for navigation are not well understood and hence a big challenge for

replication designs.

Microchiropteran bats which make use of echo-location have inspired the scien-

tists to invent radar and a deeper understanding of ultrasonic waves. Recently many

advances came in radar technology. We are able to model the terrain using Synthetic

Aperture Radar (SAR) and Multiple Input and Multiple Output (MIMO) systems

by various types of radars. Radar entomology helps us in understanding insect navi-

gation, insect flight and more about migration. Bio-navigation systems have taken

millions of years, through a process of natural selection and adaptation and hence

they are much more superior and complex in structure and function, as compared

to man-made systems. The art of flying and science of navigation in insects, birds

and bats are quite complex and not fully understood. The man-made vehicles and

their navigational procedures on the other hand are better amenable for analysis and

further improvements.

First,abriefoverviewofdifferentmethodsortechniquesofmanmadenavigational

aids, which are in use by present day scientists are explained in this chapter. Later

the navigational methods used by the biological fliers are commented upon briefly.

FinallythearticleconcludeswiththediscussiononpossibilityofusingMicroElectro-

Mechanical Systems (MEMS) for navigation in Micro Aerial Vehicles (MAVs) and

Unmanned Aerial Vehicles (UAVs).

Navigational Methods and Techniques Used by Present Day

Scientists

Many types of artificial navigational aids are designed for satellites, aeroplanes,

missiles, ships, submarines and surface transport vehicles. Some of the popular

navigational systems are explained very briefly.

Inertial Navigation System (INS)

The basic working principle of INS follows from Newton’s laws of motion. INS

is a Dead Reckoning technique of navigation, which uses the measurements of

accelerometers and gyroscopes. These two instruments fixed to the object are used to