Purdue News
Purdue NewsNOTE TO JOURNALISTS: Personnel from the National Geodetic Survey will be at the Purdue Airport on Wednesday (8/13), Thursday (8/14) and Friday (8/15) from about 7:30 a.m. to 1 p.m. each day taking data with a global positioning system receiver. For information about areas involved with in the survey, call (765) 494-2165.
WEST LAFAYETTE, Ind. -- Purdue University engineers are helping coordinate a statewide effort to establish a network of highly accurate reference points for use in surveying and navigation.
"Most of the existing reference points in Indiana were determined many years ago using older technology, so many may be in error," said Boudewijn van Gelder, professor of civil engineering in the area of surveying engineering. "Redetermining the exact position of these points using new, sophisticated global positioning system (GPS) equipment will result in much more accurate surveys."
Global positioning technology relies on gathering data from satellites using special electronic receivers. The data is then used to determine positions on the Earth very accurately.
Van Gelder is the Indiana liaison to the National Geodetic Survey, which has been using global positioning technology to measure reference points across the country for about 10 years. The national organization is responsible for measuring some 20 sites in Indiana during the next five weeks. One of those sites is at the Purdue Airport, and NGS personnel will be taking measurements there Wednesday through Friday.
About another 100 Indiana sites are being measured by a private contractor and volunteers from the Indiana Department of Transportation, the Indiana Department of Environmental Management, and various private surveyors.
Two representatives from the National Geodetic Survey are stationed near Purdue for the next five weeks to collect all the data gathered around the state. The information then will be processed and made available on CD-ROM in about a year, said Thomas Mahon, a Purdue engineering graduate student involved with the survey.
Surveyors must know the exact position of reference points in order to determine the positions of unknown points. For example, reference points are used in construction projects, property boundary surveys and locating underground utilities.
Geographic information gathered from GPS surveys also can be incorporated into graphical computer displays used by city and county planners. Pilots also use it for navigation, which is why many of the GPS reference points being measured in Indiana are at airports.
While not all surveyors use GPS technology, all will benefit from the more accurate reference points, van Gelder said.
CONTACTS: van Gelder, (765) 494-2165; e-mail, vngelder@ecn.purdue.edu
Mahon, (765) 494-2164; e-mail, mahon@ecn.purdue.edu
Purdue News Service: (765) 494-2096; e-mail, purduenews@purdue.edu
