Global Positioning System Reference
In-Depth Information
CHAPTER EIGHT
The Electronic Age
Electronic technology has led to a revolution in navigation, in terms of accuracy,
scope, and accessibility. In this chapter we see how several electronic naviga-
tion technologies work and how they have contributed to the twentieth-century
flowering of navigation.
Gyro Navigation
Gyroscopes have been around since the nineteenth century—longer, if you
include children's spinning tops. The marine gyroscopic compass (
gyro-
compass
) was invented by Dr. Hermann Anschütz-Kaempfe in 1906 and
patented in 1908. Elmer Sperry, in the United States, was hot on his heels
and patented his own device later the same year. These inventors realized
that the complicated physics of gyroscopes could be harnessed to the cause
of navigation. Both were motivated by the need for accurate navigation at
sea, in an age of increased international tensions and the building up of sea
power. Sperry's gyrocompass was quickly adopted by the U.S. Navy, and
soon such compasses were on board most ships of the navy and, later, most
ships of the world.
1
The much greater expense of gyrocompasses, as compared with the
traditional magnetic compass, is repaid in terms of increased accuracy
(typically 0.1-0.2\). The gyrocompass points to true north, not magnetic
north. It is independent of the earth's magnetic field and is una√ected by
magnetic anomalies, the ship's magnetic field, and suchlike irritations.
Another advantage of the gyrocompass is that, being an electromechanical
1. Or, to be more accurate, ships and submarines. Anschütz-Kaempfe was motivated to
invent a gyrocompass because he was interested in guiding a submarine to the North Pole.
