Land surveyors once used tape measures and transits to measure distances and positions. Since the 1980s, electronic distance measurement, or EDM, devices have allowed for a lot more efficient and accurate measurements. Find more info with a wave of energy that's shot between your EDM instrument and a reflector. Enough time the beam takes to come back is then calculated as distance. Today, such calculations can be carried out using sophisticated GPS systems.
The Global Positioning System runs on the network of satellites to precisely pinpoint the device's location on the planet at at any time. GPS uses the principle of trilateration, utilizing the location of several satellites to pinpoint an exact location. A receiver can determine the latitude, longitude, and elevation of a spot using four or even more satellites; there are always a total of 24 Global Positioning System satellites currently used. First developed by the U.S. Department of Defense as a navigational aid in 1994, today it is found in many devices, tracking from cell phones and delivery vehicles to the movement of the tectonic plates of Earth's crust.
Land surveyors use Global Position Systems to note the precise coordinates of spatial locations. Exact measurement of the positions is probably the fundamental elements of land surveying. The advantage of is that it's much more accurate than hand-measuring these locations. There's some degree of error in every land surveying measurements, because of human errors, environmental characteristics like variations in magnetic fields, temperature, and gravity, and instrument errors. GPS permits a lot more precise measurements than previously available to land surveyors using measuring tape and an angle sight.
Another benefit of the usage of its use as a land surveyor is that the coordinates could be located precisely, while other methods of land surveying depend on measurements from other known locations, like the edge of the house line, the corner of a residence, or another landmark. These locations could change over time, such as in case a house is torn down or another obstacle is built between the structure and the measured point; a good surveyor's stake may be removed prior to the land is re-surveyed. The coordinate of confirmed location on Earth, however, remains the same. Therefore, using GPS as a land surveyor produces measurements which will be accurate regardless of what happens to the encompassing land.
Although Global Position System receivers enable very precise measurements, there is still a degree of error involved. A receiver on a tripod will record the location slightly differently each time; when many measurements are taken, these data points will form a cluster round the actual location. Better-quality receivers, of course, reduce this level of error. Survey-grade receivers, rather than those designed for non-surveying uses, may create a group of measurements clustered within just one centimeter of the actual location. Today's receivers are steadily gaining in use, but may not be as accurate because the surveyor would like, especially in areas that are heavily wooded or that have other large obstructions. However, the technology is rapidly advancing and gaining a foothold in the available equipment for land surveyors. Since 1994, the accuracy available when using GPS units has improved steadily.