GPS equipment is hard for the average excavation contractor to justify

Tag : GPS system
GPS systems are high-value tools. Prior to owning GPSsystems to control his earthmoving equipment , his firm had averaged $1.5 million to $2 million in annualrevenues. Then that changed.
"Last year was our first full year using GPS systems, and wemore than doubled our annual revenue," said Jon Rood,president of Tri-County Construction Co. in Livingston, Texas.
Last year brought Rood some projects that were naturallyprofitable, but he gives much of the credit for the increase inrevenue to his GPS+ machine control systems, which automate theblade controls on two of his dozers and a motor grader. Inaddition, he uses Topcon GPS systems to indicate digging grades ontwo excavators.
"GPS equipment is hard for the average excavation contractor to justify becauseit costs as much as another piece of equipment ," says Rood. "That's why it took us two years to pullthe trigger on the purchase. After some careful research, we choseTopcon equipment , and our initial purchase cost $180,000. That is a lot of money.But six months later, the GPS equipment had paid for itself and we asked ourselves why we waited two yearsto buy it."
With 10 employees, Tri-County works primarily in east and southTexas. Throughout last year, the firm had completed six earthmovingprojects — all stakeless — using Topcon GPS systems.Two Caterpillar dozers, a D6N and a D5N, as well as a Cat 140Hmotor grader, were all equipped with Topcon's 3D GPS+ systems. ACat 330 DL excavator got a Topcon 3DXi system for indicating grade.Tri-County also bought a Topcon Hiper Lite+ base and rover with anFC 200 controller and a Topcon stand-alone base station only (norover). All of Tri-County's earthmoving machines are nowGPS-equipped.
Rood quickly counts the weeks that his GPS systems have saved: At the Willacy County Regional Detention Facility in Raymondville,the GPS systems slashed the time of grading completion to 34calendar days from the 50 days it would have taken usingconventional surveying equipment . The project involved 73,000 cubic yards of excavation, threelarge building pads and 270,000 square feet of parking. For the Maverick County Detention Facility in Eagle Pass,Tri-County spent just 28 days to move 100,000 cubic yards of earth.With conventional surveying equipment , the job would have taken 45 to 50 days, according to Jeff Rood, aco-owner of Tri-County with his brother Jon. Heaven's Gate Lake, a private 7-acre lake in Moscow, Texas,required just 11 days to move 42,000 cubic yards of earth. Roodestimated that it would have taken nearly month with conventional equipment .
In fact, Rood credits the GPS equipment with helping him to get the Heaven's Gate project over othercontractors who bid lower. The owner was an engineer who designedthe lake with multiple grade breaks to create structural habitatfor bass fishing.
"The owner asked me if it was possible to grade his lake theway he had it designed, and we assured him that since our 3-D modelwould be based on his drawings, that our grading would beaccurate," says Jon Rood. "The owner had multiplecontractors to choose from, and although we were not the lowbidder, we got the job because the owner said he was impressed withour professionalism and the amount of GPS equipment that we use. When we finished, he used our Topcon rotary laser toverify that our grades were correct." Step by Step
Jon Rood said learning to work with a Topcon GPS system is notparticularly difficult. The first step is to estimate the job usinga digitizer and cut-and-fill software. A digitizer is a large boardon which you can trace a stylus over the 2-D drawing and enter theinformation into the computer. (Tri-County uses Quest cut-and-fillsoftware.) Total square footage of the project, the building pads,the parking lots, the sidewalks, total cuts and fills, and proposedlandscape areas are all estimated.
"When we win the job, we immediately request theComputer-Aided Design (CAD) file from the engineer and we forwardit to Geoshack Services and Solutions," says Jon Rood."That's a business unit of our Topcon dealer, Geoshack. Welike having our models built by the same people that sold us the equipment . When you can mesh contractors and high technology, that is a hugeasset."
The CAD file, Rood explains, is a two-dimensional engineer'sdrawing of the project. Then Geoshack Services uses Carlsontake-off software to convert the CAD file to a usablethree-dimensional model. Field corrections can be handledimmediately by e-mail, before the model is sent to the field.
Jon Rood says that because he and his brother Jeff have extensivesurveying background, they themselves establish the control pointson the project. This is called localization, and can be done by anylicensed surveyor.
"The control points are benchmarks for GPS," says JonRood. "You have northing and easting and elevations for all ofthem."
Next he uses the Topcon Hiper Lite+ and the FC200 controller tocreate a local control file. Then he loads the control file, the3-D model and the linework file (which also comes from Geoshack)into the GPS system on the earthmoving equipment . All of that information is contained on a flash card or a USBdrive.
The base station can be set up on a known control point or anyplaceelse on the site. Jeff Rood says it takes about half a day tolocalize the GPS system — to set up the base station, load equipment with the files, and get the equipment on target. Unlike a rotary laser, a GPS base station does not haveto have sight lines to its targets — the antennae on yourearthmoving equipment .
Topcon equipment uses two constellations of satellites for positioning signals— the U.S. GPS satellites and GLONASS, the Russianconstellation of satellites. "We have never had to delay aproject because we couldn't get a GPS signal," says Jon Rood."Early in the days of GPS systems, if your satellites wentdown over the horizon, you might lose two or three hours a day ofwork." Good Dealer
"When you're buying GPS equipment , first and foremost you're buying the equipment ," says Rood. "The next key ingredient is your dealer.Our dealer is Geoshack/Houston and our salesman is Scott Bird. Ourinstaller is Matt Humbertus. I hope all dealers are asaccommodating as Geoshack/Houston."
His next project near Giddings is a $3.5-million excavation thatincludes clearing and grubbing stumps, mass excavation of 150,000cubic yards of earth, and placement of 40,000 tons of crushedlimestone base.
"We previously would have been afraid to bid this projectbecause of the stringent grading specification — plus orminus 0.05 foot," says Jon Rood. "But now we're planningto purchase Topcon's millimeter GPS grading system to help us morethan achieve the specified grades. In fact, GPS has takenTri-County Construction from being a good grading contractor tobeing a great one!"