Using GPS in Land Surveying

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Land surveying is a profession that greatly utilize the GPS system.

land surveyingToday, man-made constellations are in orbit. Their purpose is to provide instant, exact and global positioning information. This global positioning system or GPS is revolutionizing the modern construction sites, automating and guiding land surveying equipment, providing instantaneous circles and volume gap, simplifying total and controlled surveys. Nearly everyone involved in the land surveying and construction industry has heard something about satellite positioning technology or maybe you or someone you know is already using it. Whether an operator or a casual observer, there are still many questions about how this exciting system really works.

These positioning satellites don’t stay in one place like the stars; they orbit the earth about twice a day. Constantly transmitting uniquely identified radio signals that can be perceived by specialized units on earth. These signals are used to precisely measure the distance to the receiving instrument from each satellite visibly overhead.

Just as stars have exact locations in the sky, the locations of the GPS satellites are also defined, becoming orbiting reference points. Using a process based on triangulation, a GPS receiver processes the signals from multiple satellites to compute an accurate position on Earth, which is why it is widely use in land surveying.

For mobile applications that require high accuracy, such as three dimensional machine control, there are two requirements that must be met. First, the signals from a minimum of five satellites must be received at all times. And second, those five satellites must be distributed across the sky. This is called Dilution of Precision or DOP. The simple rule of thumb is this, the more satellites received the better your system will perform.

land surveyingAll land surveying receivers incorporate standard GPS tracking technology; unfortunately the GPS satellite constellation alone cannot continuously make the minimum requirement of accurate mobile positioning. For any given location, there are times in a day when there are less than five available satellites or very poor DOP.

Now, consider a land surveying job site with trees, buildings, or other obstructions when satellite receptions are easily be further reduced. All land surveying GPS receivers suffer this same problem because they all use the same satellites to operate.

Even the planned signal modernization to the GPS satellites won’t solve this problem. An obstruction that blocks one signal blocks all signals from that satellite. A land surveying equipment provider has solved this problem. The solution isn’t adding more signals from the same satellites; it’s adding more satellites.

Today, there is a second positioning satellite constellation in operation, the Glonass System. This positioning system is operated and maintained by the Russian government; much like the GPS is operated and maintained by the United States government; combining these two satellite constellations give land surveyors access to 38 different satellites; 14 more than a GPS-only system.

The additional satellites mean stronger and more accurate positions and better performance in obstructed land surveying areas. These additional satellites mean maximum up time in all land surveying locations, in all conditions.

For an up to date and accurate land surveying service, contact Columbus Land Surveying at (614) 591-8665 or better yet, you may fill out our contact form request and a licensed land surveyor will contact you. 

Land Surveyors: Leaving Their Mark

Columbus Land Surveying Posted on by

Land Surveyors are Men and women who combine their sense of adventure, their love of technology, and also their talents in making things happen with their desire to leave a lasting impression on the earth.

land surveyorsLand surveying is likely one of the world’s most vital occupations. It’s the only job qualified to form new property boundaries. Moreover, land surveyors also play a significant part in the construction of incredible architectural accomplishments – from the historical achievements that are ages old to the impressive buildings today. As a matter of fact, three of the gentlemen on Mount Rushmore were land surveyors themselves, in addition to their other more unimportant accomplishments.

Geographic Information System or GIS experts and staff rely upon surveyors for mapping details. The task of your land surveyor has shaped the world as we know it; and it all starts off with small survey markers. It might be merely a small orange survey marker, but this mark is one of the millions that the surveyor uses to take detailed measurements that would become maps which will someday become amazing buildings, new roads, master planned communities, or entire cities – and in each step along the way is a surveyor.

Land surveyors specialize in many types of surveying:

Photogrammetric surveying

In the office, a photogrammetric surveyors may be involved with map making using aerial photos ground control points. This field uses cutting-edge software and state of the art machines. Photogrammetrists themselves are typically licensed separately.

Boundary Surveying

These are land surveyors who may do in-depth research studying old maps and deeds in order to properly lay out a property boundary of a particular piece of property. Typically, we see these boundary surveys as being of larger tracts of land than the “lot survey” that is done within a subdivision. Another specific type of boundary survey is the ALTA Land Title Survey, which is typically done on a commercial parcel of land.

Construction Surveying

Construction surveyors are the power behind any growth; these people team up with engineers to ensure that the structures are constructed within the proper area and at the right location and grade. Construction surveyors also keep up with quantities for items that need to be measured and may also do an “as-built” survey at the end of construction to make sure everything is according to the design.

Hydrographic surveying

Hydrographic surveyors take their work to the lake or sea, determining depths, borders, and a lot more. This type of survey work usually uses sonar in order to determine depths and combines these readings with the exact coordinate of the sonar instrument to determine the shape of the lake or sea bottom.

Topographic Surveying

Topographic surveys are done to locate natural and man-made features on a particular parcel of land. The topo survey is different from the other types in that the elevation of the surface of the land is surveyed and represented on the resulting map of the survey. The topo survey usually also includes any man-made underground features, like utility lines. The survey will also show above ground improvements like buildings, utility poles, retaining walls, etc.

Forensic surveying

Land Surveyors may also find themselves inside the court room. On many accident scenes, the exact location of vehicles, obstacles and people at the time of accidents are helpful in determining who may be at fault and what exactly happened during the accident.  They also perform a vital role in providing expert testimonies with regards to boundaries and evidence interpretation.

Qualifications of land surveyors

With a high school diploma, anyone can begin as a surveyor technician, then on the job training would last anywhere from six weeks to a year of field training. However, in most states now licensed land surveyors must be college degree holders. Local community universities may offer programs or a two year comprehensive program in land surveying. Incomes tend to be greater than average career fields that need a 4 year college diploma or if these people acquire a degree or higher, they could begin management or one of the many specializations. Individuals working as land surveyors are among the oldest and one of the most useful professional fields.