Global Positioning System
The Global Positioning System is a 24-satellite constellation that can tell where someone or something is in three dimensions. GPS navigation and position determination is based on measuring the distance from the user position to the precise locations of the GPS satellites as they orbit. By measuring the distance to four GPS satellites, it is possible to establish three coordinates of a userís position (latitude, longitude, and altitude) as well as GPS time. Originally developed by the Department of Defense (DoD) to meet military requirements, GPS was quickly adopted by the civilian world even before the system was operational.
There are two main areas which GPS can be used in Construction: Surveying and Asset management
The main advantages of using GPS over other surveying techniques are:
- Intervisibility between stations is not necessary
- Because GPS uses radio frequencies to transmit the signals, the system is independent of weather conditions
- Because of the generally homogeneous accuracy of GPS surveying, geodetic network planning in the classical sense is no longer relevant. The points are placed where they are required (for example, in a valley), and need not be located at evenly distributed sites atop mountains to satisfy intervisibility, or network geometry, criteria
- If the same field and data reduction procedures are used, position accuracy is largely a function of interstation distance, and not of network "shape" or "geometry"
- Because of the two advantages of not requiring intervisibility of stations, or following a conventional network design strategy, GPS surveying is more efficient, more flexible and less time consuming a positioning technique than using terrestrial survey technologies
- GPS can be used around-the-clock
- GPS provides three-dimensional information
- High accuracies can be achieved with relatively little effort, unlike conventional terrestrial techniques
The Asset management system is designed to:
- have an easy, efficient way to gather, store and access the information
- be compatible with existing and future in-house GIS, accounting and administration systems
- provide operators and supervisors with current, detailed information in the field
- ensure adherence to changing legislation and provide supporting data to minimise liability exposure
- be able to easily and instantly access the data for use in budgeting, scheduling and reporting activities
- have the ability to collect GIS data quickly and easily that is compatible with full GIS systems
- be able to monitor, in real-time, the location and actual activities of all vehicles and equipment
- save time and increase accuracy for operators, generate activity reports and improve operator safety