Lasers, Robots and Machetes: Why Surveyors Use the Coolest Tools
High-tech gadgets like lasers, robots, and satellites seem more plausible as tools of the trade for Jedi Knights than for practitioners of one of the world’s oldest professions. But with a host of cutting-edge technological tools transforming how they do their jobs today, land surveyors are indeed among the most space-age pros in the field.
And surveying is the very definition of a field job: Surveyors measure land areas to establish legal boundaries and determine proper placement of all the intricate details that go into the construction of roads, buildings, office parks, residential developments, and so forth. But for nearly 6,000 years, from the days of ancient Egypt all the way until the late 1970s, surveyors used pretty much the same technology to perform their measurements: a measuring rope.
The only thing that really advanced during those thousands of years was the material. Ancient Egyptians would stretch a rope from one point to another to measure distances, but that was eventually replaced by a metal chain and later by a steel reel.
But over the last 30 years — affordable laser technology made its way into the hands of land surveyors in the late 70s — the rate of technological advancement has accelerated to warp speed, substantially reducing the amount of time and number of crew required to conduct highly detailed and precise surveys on a massive scale.
Mitch Evans, 50, who started working as a surveyor in his dad’s business as a teenager (using the low-tech survey chain as his primary instrument of measurement), has witnessed this quantum leap first-hand. Here are some of the coolest tools of the trade Evans, now president of Kirkland, Wash.-based Axis Survey and Mapping, says have revolutionized the world’s second-oldest profession.
Lasers: Electronic Distance Meters (EDM)
Evans recalls how much lasers simplified and shortened the measuring process when EDMs came on the market in his late teens. “It used to be that we needed two extra guys on a crew to stop traffic in both directions so I could pull the [measuring] chain across the road,” Evans says. “The steel had to be cleaned a certain way. It had to be kept in a certain order, rolled up and reeled up every night. It was all a pain-staking process.”
With the laser, however, you don’t need to pull a chain across the road. Instead, you aim the laser, mounted on a tri-pod, toward a prism, which is a piece of reflective glass, held by another crew member. The prism reflects the light back to the EDM, which calculates measurements within a second.
“With the EDM, we could go from a four-person crew to two people,” Evans says. “When I was a kid that was the coolest thing since rubbing two sticks together to get fire. It was amazing.”
Robots: The Total Station
Robotic total stations took EDM technology to the next level. Instead of requiring two people – one person operating the laser and the other holding the prism – the robot enables a single operator to both hold the prism and control the laser from a distance via remote control.
Despite the $50,000 price tag, Evans sees the economic benefits. “[The robot] never complains; it doesn’t have to take coffee breaks; it doesn’t have to take a pee. All it needs is some batteries to run for a while AND not get run over by a UPS truck,” Evans quips. “Now the crew can be just one guy or, if needed, we could get four times more work done with a two or three-person crew.”
Satellites: Global Positioning Systems (GPS)
One of the challenges with surveying is making sure that you have clear “line of sight,” which means you can’t have anything blocking the straight line between the laser and prism. So, when it comes to measuring land areas with mountains or other steep terrain or deep woods, it would take several days to complete — that is, before highly accurate GPS technology came along about 15 years ago.
The impact? “If we were taking a measure that’s four or five miles away, we had to physically measure 300 feet at a time, which would take 3-4 days worth of work,” said Evans. “The GPS allows us to achieve accuracies down to one-eighth of an inch and take a four-day measuring process down to four hours and get it done in a morning.”
3-D Laser Scanner
While the standard EDM captures one measurement per second and requires a prism to reflect back the light, a three-dimensional (3-D) laser scanner takes 50,000 measurements per second, without the need of a prism. The 3-D Laser takes random shots that bounce light off everything in its path, with an effective range of 400-500 feet. The result is a three-dimensional model of the scanned area, with precise measurements and every detailed imaginable. “I can even see cracks in the concrete,” said Evans.
It comes with a hefty price tag — about $120,000 — so Evans doesn’t equip all his trucks with it. But he is finding new markets that help justify the investment.
“We’re getting calls from video game developers saying, ‘We’re trying to build an accurate three-dimensional model. So we want to do a street race down the downtown Seattle corridor. How much would it cost us to map everything you would see at street level if you were driving a race car down Fourth Avenue in downtown Seattle?’ We go down to the corridor and scan it to get an accurate three-dimensional point cloud from which to build their ‘fake’ three-dimensional world for a video game,” Evans says. “Very, very friggin’ cool stuff.”
Mobile Mapping System
Now, imagine you could take a 3-D Laser Scanner and GPS, securely mounted on top of a vehicle, and conduct a “drive-by” survey of an area at 40 miles an hour. How much time would that capability save a survey crew? That’s precisely what a Mobile Mapping System does.
How accurate are the images captured at high rates of speed?
“I can drive by a power pole during my scan, come back to the office, look at the point cloud data I gathered while driving, and read a number off a power pole that was scanned,” Evans says.
Peering through his crystal ball, what other technologies does Evans see coming?
Aerial drones, equipped with mobile mapping equipment, Evans predicts. “I could sit here at my desk and play it like a GameBoy doing a survey. And while I’m talking with you on the phone, I’m droning by your house, figuring out what it is I’m supposed to be shooting, and by the time you and I finish our conversation, I’m sending you a map. That’s what’s next.”
While the technology exists today, the multimillion-dollar price tag has made it too cost prohibitive for wide spread adoption among surveyors, he says.
Keep in mind, not all tools surveyors use are high-tech gadgets. Evans says he still lines his tool belt with the old-school stuff, like hammers, machetes, and brush cutters – but the machete is one of his favorites.
“We use machetes in the woods or if I’m surveying down the side of someone’s property and need to clear stuff out of the way so that we have clear line of sight,” said Evans. “But sometimes it’s really nice to have when you’re down in the really nasty sections of town, where you’re not going to clear any brush but you’re worried about people stealing your stuff. You wear [the machete] so you have their undivided attention. They think, ‘You know, I could steal this guy’s $40,000 total station, but he’s wearing this two-and-a-half-foot blade on his side. I better not [mess] with him.’”
What are the coolest tools of your trade? What new technologies have emerged? How have they transformed your business?
“[The robot] never complains; it doesn’t have to take coffee breaks; it doesn’t have to take a pee. All it needs is some batteries to run for a while AND to not get run over by a UPS truck."