Connecting the Laser Dots

As a result of the demand for information on highways, cityscapes, railroad right-of-ways, Tulsa-based Aerial Data has acquired an innovative tool for collecting 3D data of large areas and corridors in conditions that do not allow for traditional photogrammetric methods.
Aerial Data, 301 E. 51st Street, Suite 100, is using the next generation of mobile light detection and ranging, or LiDAR, equipment to extend its mapping characteristics. LiDAR has been around in some form since the mid-1990s.
The demand for mobile LiDAR systems has increased, as more areas have to be surveyed at an accuracy and resolution level that exceeds those available through traditional aerial photography and photogrammetry. The process has become necessary to establish location, direction and position. Using a static LiDAR is system is impractical for most projects today. The mobile mapper captures high-accuracy, high-density points, allowing easy and precise identification of objects.
“Aerial LiDAR is an innovative tool for extracting and producing surface models for large areas and corridors in conditions that do not allow for traditional methods,” said Eric Andelin, Aerial Data vice president.
Interest in Aerial Data’s product is coming from south of the Red River, Andelin said.
The Texas Department of Transportation has generated enough business to justify opening an office in the Texas capital in 1998. On average TXDOT is about 65 percent of total highway work at ADS, Andelin said.
“However, If you combined direct ODOT work with the consultants who use ADS for ODOT projects, ODOT might be a larger percentage,” he said.
Genesis
Pioneers mounted LiDAR systems to airplanes and flew from location to location, collecting data from above. Later, stationary terrestrial systems were developed and mounted on survey tripods to collect their surroundings.
The next step was to place a terrestrial system on a vehicle to collect data as the crew drives from place to place, said Andelin.
Crews can drive up to 300 miles a day on projects, mapping for government agencies, private individuals or companies.
The latest LiDAR equipment allows Aerial Data to obtain survey grade data at true highway speeds, in excess of 65 mph. Using a two-sensor system capable of firing 200,000 points per second per laser, point densities of 10,000 points per square meter are possible. The device “paints” everything — buildings, bridges, trees, poles, fences, power lines, other traffic, the road — with laser beams. The device fires hundreds of thousands of pulses calculate each pulses location and the intensity of its return to create a picture. The mountain of data is used to build a 3D representation of anything within 200 meters of its path.
“There is a ton of data,” Andelin said. “There are hundreds of thousands of points created and plotted. They are assigned a color value to create a color photo.”
Outer Limits
There are limitations to the data that aerial systems collect. Some limitations include tunnels, bridges, and vertical features for architectural work and asset inventory.
“Think of it this way: When you look down on a pole or sign from an aerial photo, you see it from a top down view. With our mobile system, you see it as you’re used to — from an immersive view,” said Andelin. “You can see not only a sign, but what that sign says. Which is not possible with data from aircraft.”
Founded 45 years ago, Aerial Data Service has moved from being a small business to a technological trendsetter. ADS relies upon its years of experience to produce accurate aerial photos, digital maps and geospatial maps.
Local businesswoman Regina Carter bought the company in 1984 from the original owner, Jack Beindorf. Carter has overseen the growth of ADS from 10 employees to 35 and its expansion to include a second location in Austin.
ADS serves a variety of clients including civil engineering firms, departments of transportation for five states, municipalities, airports, railroads, utilities, oil companies and developers.



Was this article helpful?

Related Articles

Leave A Comment?