The Global Positioning System (GPS) is a satellite navigation system that allows users to determine their exact locations. GPS was initially developed for military use but has proved to be essential for emergency services and air traffic control. In recent years it has been increasingly used in construction.
GPS systems were first incorporated into construction surveying systems in 1982. Eleven years later the first mining machines were using GPS systems and in 1999 some construction machines were fitted with the application. Since 2002 Caterpillars and certain excavation machines have been factory fitted with GPS receivers.
GPS devices in construction are mainly used for mapping and surveying sites. With the help of satellite signals, distances, depths and elevations can be determined precisely. Commercial and large building projects have machinery fitted with GPS on site. These systems have been programmed with coordinates from the building plans to indicate, among others, digging locations or hazardous areas. Machines are also fitted with GPS devices to allow tracking in the event the equipment is stolen.
Pre-construction schedules have been reduced significantly with the use of GPS technology. Previously, location mapping took weeks to measure, while GPS now allows surveyors to determine site dimensions within hours. The system also reduces health and safety issues, as it allows workers to locate hazards, such as underground utility lines, more accurately.