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Marine

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????:??. ????????. Marine. Navigation & Positioning Systems. ???? ?????? ... Bonfires along shorelines at key locations. Migratory seabirds. ????? Brief History ... – PowerPoint PPT presentation

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Title: Marine


1
???????? Marine Navigation Positioning Systems
  • ??????

2
???? Agenda
???? ?????? ???? ?????? ???? ?????? ????
?????? ???? ??????
3
???? ?????? Introduction to Navigation
4
1 ????? What is Navigation ?
5
????(Navigation)???
  • Latinnavigare
  • Navis ship
  • Agere to direct, conduct
  • Navigation
  • the process of safely and efficiently directing
    the movements of a vessel from one place to
    another.

6
??????? Brief History of Navigation
  • Commerce and conquestperhaps the two greatest
    drivers of human civilizationhave always
    depended on accurate navigation.

7
????? Brief History
- The history of human navigation goes back
thousands of years. - The first seafarers kept
in sight of land that was the first trick of
navigation Typically, ancient mariner remained
close to shore and used geographic landmarks to
guide thema technique known as piloting.
8
????? Brief History
  • But what if land were nowhere nearby? The
    Phoenicians looked to the heavens.
  • The sun moving across the commonly cloudless
    Mediterranean sky gave them their direction and
    quarter. The quarters we know today as east and
    west the Phoenicians knew as Asu (sunrise) and
    Ereb (sunset), labels that live today in the
    names Asia and Europe. At night, they steered by
    the stars.
  • - The Greeks and Phoenicians made great strides
    in navigation and developed techniques that
    remained in use for thousands of years.
  • Pole star
  • Bonfires along shorelines at key locations
  • Migratory seabirds

9
????? Brief History
Also a Simplified dead reckoning was used by
Mediterranean mariners The ship's
speed was determined by watching seaweed or
driftwood, travel time by an hourglass, and
heading by guesswork and institution,
until around 1100 AD, when the Chinese
created the first magnetized needle
compass.
Chip log
hourglass
10
????? Brief History
The greatest advance in navigation came with the
compass. The Chinese apparently knew about the
powers of magnetism as early as the third
millennium B.C., when, historians tell us, one
army defeated another by using a device known as
a "point-south carriage." (The Chinese chose to
have the arrow point south rather than
north.) The first mention of the compass in the
West comes from the Englishman Alexander Neckham,
who wrote in 1187 that "sailors use a magnetic
needle which swings on a point and shows the
direction of the north when the weather is
overcast."
11
????? Brief History
  • 12th and 13th centuries brought several
    navigational advances to Europe
  • nautical charts
  • celestial almanacs
  • astrolabe "astro" means star and "labe"
    means 'to find.
  • cross-staff
  • astrolabe made in Lisbon by J. de Goes in 1608,
    now in the Museum, Italy

Cross staff
12
????? Brief History
  • - The Arabs used a simple device called a kamal
    to make the observation

Mariners brass quadrant. The quadrant shown here
is a replica of the type Columbus might have used
on his voyages to the New World.
  • Before leaving homeport, the navigator would tie
    a knot in the cord so that, by holding it in his
    teeth, he could sight Polaris along the top of
    the transom and the horizon along the bottom.
  • - Explorer tries any way to find the latitude of
    their position. Quadrant was developed around the
    turn of the 17th century.

13
????? Brief History
Finding latitude with the Pole Star and noontime
Sun
 Position of the noon Sun  at the summer
solstice
The angle ? of the pole star above the horizon
equals the local latitude
Position of the noon Sun at the winter solstice
? a e a 23.5
? a - e a - 23.5
14
????? Brief History
  • - Subsequent advances in optics led to the
    invention of the sextant in 1731.

Around 1730, an English mathematician, John
Hadley (16821744), and an American inventor,
Thomas Godfrey (17041749), independently
invented the sextant.
15
????? Brief History
- Still, while latitude measurement improved,
longitude measurement remained out of reach.
England established a Board of Longitude in 1714
and offered 20,000 pounds sterling to whoever
could resolve it. John Harrison trumped them all
by building a chronometer in 1764 that lost less
than one second per day during long sea voyages.
16
????? Brief History
In 1779, British naval officer and explorer
Captain James Cook used Harrison's chronometer to
circumnavigate the globe. When he returned, his
calculations of longitude based on the
chronometer proved correct to within 13
kilometers (8 miles).
South-Pacific Routes The first voyage is shown in
red, second voyage in green, and third voyage in
blue.
James Cook, British Navigator and Explorer
(17281779)
17
????? Brief History
In 1884, at the height of the British Empire,
Greenwich, England, was established as the
world's Prime Meridian. After a period of
relative quiescence, the 20th century brought an
unprecedented wave of navigational advances.
18
????? Brief History
In 1907 American Elmer Sperry introduced the
gyroscopic compass which is unaffected by
variation or deviation as it points to true
north, not magnetic north. By the 1920s, the
development of radio navigation was underway.
In 1935, British physicist Robert Watson-Watt
produced the first practical radar system By
1939, a chain of working radar stations was in
place along the south and east coasts of
England. Inertial Guidance System was equipped
by German Army in V-2 Rocket. The hyperbolic
navigation system known as Loran was developed in
the U.S. between 1940 and 1943. GPS,initiated
in 1973, operated and maintained by the U.S.
Department of Defense, was established in 1994.
19
????? Brief History
But the story is far from over. As civilization
reaches farther into spacewhere terms such as
"horizontal" and "vertical" hold little
meaningnew navigational techniques will be
required. As space vessels venture out beyond
the reaches of the inner solar system, they will
encounter new navigational challenges.
20
????????? ??(??Longitude???Lat
itude? ??Altitude) ??(??????????????)
Velocity Speed? ??(Heading) ??(Attitud
e Roll, Pitch, Yaw) ??(Time) ??(Water
Depth) ??(Depth of Submarine)
21
????????????? Positioning means to determine
location Guidance means to conduct a vehicle,
usually unmanned, to arrive the destination by
means of control techniques based on
navigation Piloting involves navigating in
restricted waters with frequent determination of
position relative to geographic and hydrographic
features
22
Navigation Department Administrative Organization
23
Navigation Department Operational Organization
24
The Bridge Team
  • Officer of the Deck (OOD)
  • Conning Officer
  • Quartermaster of the Watch (QMOW)
  • Boatswains Mate of the Watch (BMOW)
  • Lookouts
  • Helmsman

25
  • Bridge (Piloting)
  • Navigator
  • Plotter
  • Bearing Taker
  • Brg Recorder

OOD
Conning Officer
CO
Bearing Taker
Bearing Taker
Chart Table
Navigator
Bridge
Plotter
Bearing Recorder
  • CIC (RadNav)
  • Piloting Officer
  • Radar Operator
  • Plotter


CIC
Chart Table
Radar Operator
Piloting Officer
Plotter
26
???????(Types Of Navigation)
Commonly recognized types of navigations
are listed below. 1. ????(?????????) Dead
reckoning (DR) 2. ???? Celestial navigation 3.
????(????) Terrestrial navigation 4. ????? Radio
navigation 5. ???? Radar navigation 6. ????
Satellite navigation 7. ???? Inertial Navigation
8. ????(????) Integrated Navigation 9. ????
Meteorological navigation
27
???????(Types Of Navigation)
  • Dead reckoning (DR)
  • also called Deduced Reckoning, is a
    technique to determine a ship's approximate
    position by applying to the last established
    charted position and a vector or series of
    vectors representing true courses and speed. This
    means that if we have an earlier fix, we plot
    from that position our course and 'distance
    traveled since then' and deduce our current
    position.
  • Celestial navigation
  • involves reducing celestial measurements to
    lines of position using tables, spherical
    trigonometry, and almanacs. It is used primarily
    as a backup to satellite and other electronic
    systems in the open ocean.

28
???????(Types Of Navigation)
3. Terrestrial navigation fixes the
vehicles position by landmarks or charted
NAVAIDS. Fixed by Two Bearing Lines
Three Bearing Lines
Two Ranges
Three Ranges Fixed
by Bearing and Range Fixed by
Running Fix Bearing ? Heading ???? 4.
Radio navigation uses radio waves to
determine position by either radio direction
finding systems or hyperbolic systems.
29
???????(Types Of Navigation)
  • Radar navigation
  • uses radar (radio detecting and ranging) to
    determine the distance from or bearing of objects
    whose position is known. This process is separate
    from radars use as a collision avoidance system.
  • (ARPAAutomatic Radar Plotting Aids)
  • Satellite navigation
  • uses artificial earth satellites for
    determination of position, such as GPS, GLONASS,
    Galileo and Beidou?
  • Inertial Navigation
  • is a totally self-contained navigation
    system providing vehicles position in response
    to inertial effects on system components.
  • Gimbled INS (Platform INS)
  • Strapdown INS

30
???????(Types Of Navigation)
  • Integrated Navigation
  • is a combination of two or more than two
    methods or equipment of navigation to get more
    accurate position, attitude and speed fixing.
    Integrated Bridge System (IBS) is a typical
    integrated navigation system that takes inputs
    from various ship sensors, electronically display
    positioning information, and provide control
    signals required to maintain a vessel on a preset
    course.
  • Meteorological navigation

31
Four distinct phases define the navigation
process. The mariner should choose the system mix
that meets the accuracy requirements of each
phase.Inland Waterway Phase Piloting in narrow
canals, channels, rivers, and estuaries. Harbor
/Harbor Approach Phase Navigating to a harbor
entrance and piloting in harbor approach
channels.Coastal PhaseNavigating within 50
miles of the coast or inshore of the 200 meter
depth contour.Ocean Phase Navigating outside
the coastal area in the open sea.
?? Phases Of Navigation
32
????(The Earth)
33
????(The Earth)
Earth A not-so-perfect Sphere
For navigational purposes, its considered a
true sphere with a circumference of 40,200 km
34
Terrestrial Coordinate System
  • Earth - The Earth is a spheroid, but for
    navigational purposes, it is considered a
    perfect sphere with a circumference of 21, 600 n
    m.
  • On a sphere at rest, any point on the surface
    is similar to any other point so reference
    points must be designated in order to make
    measurements on the spheres surface.
  • When rotation is introduced, two reference points
    are defined - the points at which the spin axis
    pierces the surface of the sphere. On the Earth,
    these points are called the north and south
    poles.
  • The axis of the Earth, together with its poles,
    constitutes the basic references on which the
    terrestrial coordinate system is based.
  • Great circle - The intersection of a plane
    passing through two points on the surface of
    the earth and the center of the earth.
  • The resulting circle is the largest circle that
    can be drawn on the surface of the earth.
  • The resulting line on the surface of the earth
    represents the shortest distance between the two
    points.

35
Great Circle
Meridian
Plane Great Circle
36
Terrestrial Coordinate System
  • Equator - The great circle formed by passing a
    plane perpendicular to the earths axis halfway
    between its poles . The equator divides the earth
    into northern and southern hemispheres and is of
    major importance because it is one of the two
    great circles from which all locations on the
    earths surface are referenced.
  • Small circle - Any circle not passing through
    the center of a sphere .

37
Small Circle
38
Terrestrial Coordinate System
  • Meridian - Any great circle formed by passing a
    plane through the center of the earth at right
    angles to the equator.
  • Prime Meridian - The meridian that passes through
    the original position of the Royal Greenwich
    Observatory near London, England.
  • The prime meridian constitutes the second
    reference line for the terrestrial coordinate
    system. All other meridians are referenced to
    the prime meridian it divides the earth into the
    eastern and western hemispheres.
  • All meridians lie in a true north/south direction
    and are bisected by the earths axis. The half
    of a meridian extending from the north to south
    pole on the same side of the earth as an observer
    is called the upper branch. The other half, on
    the opposite side of the earth is referred to as
    the lower side.
  • The upper branch of the prime meridian is
    frequently called the Greenwich meridian while
    the lower branch is called the 180th meridian.

39
Terrestrial Coordinate System
  • Longitude - The angular distance between the
    Greenwich meridian and the meridian of a
    particular point on the earths surface.
    Longitude is measured in degrees of arc from 0 to
    180 degrees.
  • If a point lies between 0 and 180 degrees east
    the of the Greenwich meridian, it is described
    as having eastern longitude.
  • If a point lies between 0 and 180 degrees west of
    the Greenwich meridian, it is described as having
    western longitude.
  • Longitude is abbreviated by the Greek letter
    lambda ( ) or LO.
  • Latitude - Any small circle perpendicular to the
    earths axis formed by passing a plane parallel
    to the plane of the equator.

40
Longitude and Latitude
300 60nm/deg 1800nm
1-6
41
Terrestrial Coordinate System
  • Latitude is measured along a meridian. The
    length of one degree of latitude is the same
    everywhere on earth (60 nm).
  • Longitude is measured along parallels of latitude
    , which are small circles with the exception of
    the equator. One degree of longitude will not
    equal 60 nm except when measured along equator.
    At all other locations, as the distance from the
    equator increases, the length in miles of one
    degree of longitude decreases.

42
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