Survey Technology Sets Higher Stakes

GPS upgrade boosts grading productivity and accuracy.


In addition, Sorrell was able to use the GPS900's Nearest Point feature to quickly verify utility locations in each subdivision. The feature automatically looks at all the points yet to be staked out, calculates a distance from the current position to all remaining stakeout points, then selects the shortest distance to the next stakeout point.

"On this project, we checked 100 sewer laterals along the right-of-way for the county inspector, and it took 15 minutes. I just walked to the point, hit one button and it quickly read how close I was to the intended point," says Sorrell. "We use this feature daily. Its compatibility with CAD saves a few steps because there is no need for data conversion.

"Bottom line, GPS is a critical resource to our company," he adds. "We can't afford to do business without it, and fortunately, it's now available at a price point we can support with functionality that exceeds our expectations." ?

Staying Connected
With every GPS tool, the user is at the mercy of the available satellite signals. When those signals get dropped, the equipment must make adjustments to the data — in some cases, with disastrous results.

Ellis Astin's John Sorrell recalls one topographic survey project using a different GPS product. "It was a simple topographic survey of a relatively flat field. I lost the signal from the GPS about halfway through the survey, so I paused and waited for it to return. It did and I moved on," he notes. "During post-processing, I noticed there was a big valley that appeared in the middle of the field. I knew that wasn't right." It turns out the GPS tool had picked up the wrong signal in the middle of the field.

The Leica GPS900, on the other hand, is equipped with SmartCheck, which performs two independent checks — one every four seconds — on the GPS signal. "Our GPS900 ensures we don't have that mistake again," Sorrell states.