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Although these parameters limit the usefulness of the RTK technique for general navigation, the technique is perfectly suited to roles like surveying. In this case, the base station is located at a known surveyed location, often a benchmark, and the mobile units can then produce a highly accurate map by taking fixes relative to that point.
It is the most accurate technique currently available to determine the geocentric position of an Earth satellite, allowing for the precise calibration of radar altimeters and separation of long-term instrumentation drift from secular changes in ocean surface topography. Satellite laser ranging contributes to the definition of the international ...
Precise positioning is increasingly used in the fields including robotics, autonomous navigation, agriculture, construction, and mining. [2]The major weaknesses of PPP, compared with conventional consumer GNSS methods, are that it takes more processing power, it requires an outside ephemeris correction stream, and it takes some time (up to tens of minutes) to converge to full accuracy.
Total stations are the primary survey instrument used in mining surveying. A total station is used to record the absolute location of the tunnel walls, ceilings (backs), and floors, as the drifts of an underground mine are driven. The recorded data are then downloaded into a CAD program and compared to the designed layout of the tunnel.
StarFire is a wide-area differential GPS developed by John Deere's NavCom and precision farming groups. StarFire broadcasts additional "correction information" over satellite L-band frequencies around the world, allowing a StarFire-equipped receiver to produce position measurements accurate to well under one meter, with typical accuracy over a 24-hour period being under 4.5 cm. StarFire is ...
Real-time kinematic positioning (RTK GPS) is employed frequently in survey mapping. In that measurement technique, unknown points can get quickly tied into nearby terrestrial known points. One purpose of point positioning is the provision of known points for mapping measurements, also known as (horizontal and vertical) control.
A direct-readout theodolite, manufactured in the Soviet Union in 1958 and used for topographic surveying. A theodolite (/ θ i ˈ ɒ d ə ˌ l aɪ t /) [1] is a precision optical instrument for measuring angles between designated visible points in the horizontal and vertical planes.
Surveying with a chain is simple if the land is level and continuous—it is not physically practicable to range across large depressions or significant waterways, for example. On sloping land, the chain was to be "leveled" by raising one end as needed, so that undulations did not increase the apparent length of the side or the area of the tract.