船 舶 导 航 定 位 系 统
（Marine Navigation and Positioning
Systems）
授课学时：32学时 授课专业：测控技术 课程类型：指选课 教学方法：双语教学
自动化学院 Automation College
赵 琳 Lin Zhao
Marine Navigation and Positioning Systems
Marine navigation blends both science and art. A good navigator gathers information from every available source, evaluates this information, determines a fix, and compares that fix with his pre-determined ―dead reckoning‖ position. A navigator constantly evaluates the ship‘s position, anticipates dangerous situations well before they arise, and always keeps ―ahead of the vessel.‖ The modern navigator must also understand the basic concepts of the many navigation systems used today, evaluate their output‘s accuracy, and arrive at the best possible navigational decisions. Navigation methods and techniques vary with the type of vessel, the conditions, and the navigator‘s experience. Navigating a pleasure craft, for example, differs from navigating a container ship. Both differ from navigating a naval vessel. The navigator uses the methods and techniques best suited to the vessel and conditions at hand. Some important elements of successful navigation cannot be acquired from any book or instructor. The science of navigation can be taught, but the art of navigation must be developed from experience.
What will we learn from the lecture?
? Some basic knowledge on earth, coordinate, nautical
chart, dead reckoning, landmark fixing and so on; ? Some basic principle of navigation systems, such as
celestial navigation, radio navigation, radar navigation, satellite navigation, inertial navigation, integrated
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navigation system, and so on.
Can you tell the difference among: Navigation: Guidance: Positioning:
###PLANS----Position, Location And Navigation Symposium
Part 1 Introduction to Navigation
1.1 What’s navigation
Navigation: The theory and practice of navigating, especially the charting of a course for a ship or an aircraft. Or the method used to guide a vessel from departure point(起航点) to its destination.
Navigation System: The system or device that can be used to guide a vessel to its destination. 1.2 Brief History of Navigation
- 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 them—a technique known as piloting.
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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
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. 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 \south rather than north.) The first mention of the compass in the West comes from the Englishman Alexander Neckham, who wrote in 1187 that %use a magnetic needle which swings on a point and shows the direction of the north when the weather is overcast.\Around 1730, an English mathematician, John Hadley (1682–1744), and an American inventor, Thomas Godfrey (1704–1749), independently invented the sextant. Still, while latitude measurement improved, longitude measurement remained
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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. 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). 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. 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.
But the story is far from over. As civilization reaches
farther into space—where terms such as \hold little meaning—new navigational techniques will be required. As space vessels venture out beyond the reaches of the inner solar system, they will encounter new navigational challenges.
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