
The Rapid Evolution of Navigation
Progress is wonderful: consider for instance
the way that no deposit car insurance company
lowdepositcarinsurance.org.uk has reduced car insurance costs so
much! Man has navigated by the stars, since
he took a pen to paper and recorded history. Whilst we still
generally look to the heavens for directional guidance, the methods
and standards have evolved at a breakneck pace in the past few
hundred years. The technology that gave birth to the sextant and
astrolabe exploded into radio communication and finally to launching
man-made stars into space. The devices to navigate by them and the
proliferation into all forms of transportation is equally
remarkable. Maps are still widely used, but a combination of
satellite and computer technology has enabled map-making to move
beyond two dimensional lines on paper to virtual photographs of
topography.
Longitude and latitude are still the generally accepted positioning
standard for expressing a particular location. The nomenclature is
relative to the equator which divides the earth into a Northern and
a Southern hemisphere, and the Greenwich or Prime Meridian which
divides the earth East and West. So, 41° 58' 41" N and 87° 54' 22"
W, which as it happens, is Chicago’s O’Hare International Airport,
is 41 degrees, 58 minutes and 41 seconds north of the Equator and 87
degrees 54 minutes and 22 seconds west of the Prime Meridian.
The “where” is easy to understand in comparison to the “how.” Until
very recently, modern military navigation has been primarily
facilitated by Long Range Navigation or LORAN, a terrestrial radio
system utilizing numerous transmitters to track receivers on
seagoing vessels. The Russian-American and Canadian LORAN chains
remain in use, though the technology seems to be largely on the way
out.
GPS has most definitely asserted itself as the state of the art. The
placement of global positioning satellites (GPS) into space enables
us to look back at the earth in such a way as to precisely locate a
variety of vessels from a merchant ship to the family van down to
longitude and latitude. Although GPS has also taken its place on
airplanes, radios and receivers still play a large part in
navigating inner space. Commercial airliners use radio signals and a
varied combination of onboard devices such as IRS (Inertial
Reference System) and INS (Inertial Navigation System), which rely
on first being told where they are starting from in order to
determine where they are en route.
However, while GPS is a great method to navigate, find your way from
one place to a pre-determined destination, it enables monitoring and
control of transportation systems such as rail and trucking. GPS
data transmitted computer networks facilitate the safe and effective
operations of truck fleets and railroads.
The reliance on satellite and computer technology for navigation and
navigational information management, while effective, has introduced
an ominous undertone of “what if.” The common nature of
communications and computer failures will likely leave radio
antenna-based navigational systems in a back-up position for years
to come. The human element in navigation should be equally on
notice. In the face of technology failure, skills like map reading
and terrestrial navigation come in very handy.
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