One of these technological advances is that presently our survey crews are able to access the satellite signals of the Global Positioning System (GPS) with our Leica receivers. When the GPS receivers are operating in the real-time kinematic (RTK) mode, an accurate location can be obtained in less than 10 seconds thus saving valuable time for our client.

For example, topographical data of the project can be gathered by the combination of land and aerial surveying. Utilizing GPS, the land surveyor can locate aerial targets that have been set under the direction of the aerial surveying company who can provide us with digital aerial photographs and/or digital aerial topographic maps showing the digital terrain model (DTM). According to Jesse Cochran of Williams Stackhouse, Inc., an aerial surveying firm in San Antonio, Texas, the number of the aerial targets required depends on whether Williams Stackhouse uses one of its more conventional methods or, if the project warrants, a new method can be used called “Airborne GPS” in which 3 GPS receivers “talk” to each other. Two of the GPS units are located on the ground and one GPS unit is located in the airplane. Both methods yield excellent results both horizontally and vertically but the Airborne GPS requires less ground control (less time and money).

Topographical data and the DTM can also be obtained by more conventional land survey methods. One method could utilize RTK GPS and The Wallace Group’s 6 wheel all-terrain vehicle (allowing for quicker collection of field data) or another method using the now “old-fashioned” electronic total station. Both methods’ information is automatically downloaded into an electronic data collector which is then easily downloaded into the office’s computer local/wide area network (LAN/WAN).

Our planners and/or architects then can use the digital aerial photographs, the aerial digital topographic maps and/or the DTM to develop a concept of the project, the engineering staff can use the same to design the project and prepare construction plans. The surveyors can “download” the completed job from the office computers back into their data collectors then accurately and efficiently stake the project on the ground based on the engineer’s design (possibly utilizing GPS once again).

From start to finish, The Wallace Group endeavors to utilize the latest in technology to provide its client the best service possible.

Author: Webmaster