Conventional surveying methods

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Conventional surveying methods are time consuming and costly. They often requie multiple trips to the same area to make sure that the collected data is accurate. They can also be delayed by bad weather such as high winds or torrential rain. Generally surveying with GPS requires a base receiver and a roving receiver.

Traditional use of GPS for surveying requires two receivers (one as a base station and one as a rover). OS Net-enabled services does not require this, as information for corrections is fed directly to user's GPS device without the need for a base station. This means that expensive GPS units can be used at double the efficiency (as only one is needed per operator), and this saves time and money. The Utah Department of Transportation found that one person operating GPS equipment is generally twice as fast as a conventional survey crew, and a GPS system with two units is potentially four times faster than crews using conventional surveying technologies. Other advantages of GPS technology include the ability to use the technology across long distances with minimal setups. After a GPS system is placed, roving can be performed within a radius of 10 kilometers (6 miles) of the stationary base unit. Using conventional technologies, the base unit would have to be moved every 183 meters (600 feet).

In one study, GPS equipment recorded 5,511 topographic points in 30 person-hours, while a similar project using conventional technologies covered only 1,500 topographic points in 120 person-hours.

Utah, Michigan, and North Carolina are the lead States of the American Association of State Highway and Transportation Officials'Technology Implementation Group (TIG) initiative to champion GPS for surveying applications. Plans include hands-on demonstration workshops and training programs for agencies that plan to apply GPS to surveying efforts. The GPS TIG group also is considering developing nationals tandards and protocols for GPS programs.

No lengthy local network establishment As OS Net is a network solution, all base stations are already established within the OS Net network. This avoids the hassle and expense of establishing local control for any surveying work. This makes use of high-precision GPS more flexible and quicker and therefore more cost effective.

Putting it in Perspective

  • It takes many days to survey small sections of road using traditional techniques.
  • Complete road inventories may take years.

Successful Applications: Research Indicates Improved

Survey Accuracy and Reduced Costs

Can work anywhere (subject to GPS and correction signal availability)

An OS Net-enabled serviceis anational service covering most of Great Britain. This means that as long as you have a GPS signal and some means of receiving correctional data, you can usethe serviceanywhere in Great Britain. This Solution: GPS Increases Survey Accuracy, Improves Productivity, and Reduces Costs Over the past 5 years, studies across the United States have shown that GPS technology increases the productivity of conventional survey crews, reduces data collection time, improves survey accuracy, and allows crews to work under a broad range of weather conditions.

Moreover, less expertise is required to operate a GPS surveying unit than is needed to operate conventional surveying technologies.

What is GPS?

GPS is a space-based, radio-navigation system that provides worldwide, all-weather, three-dimensional position, velocity, navigation, and time data to both civilian and military users. Potential uses for GPS within the highway community are diverse and range from providing traveler information to mapping (GPS technology can be integrated easily with Geographic Information Systems).

How does it work?

GPS can provide a very accurate digital map of the highway infrastructure. The technology operates on the principle of triangulation-if the difference from an observer to three known points can be measured, the position of the observer can be calculated. The system includes at least 24 satellites in orbit 19,320 kilometers (12,000 miles) above the earth and inclined at 55°.

These satellites continuously broadcast their position, a timing signal, and other information. By combining the measurements from four different satellites, users with receivers can determine their 3-dimensional position, currently within 4-20 meters (13-66 feet). Allows great flexibility in operations.