The abilities of BIM systems, augmented reality, and the overlaying of data layers to enrich surveys and blueprints have given surveyors and engineers more information than ever before. Now you can add affordable LiDAR scanners to the mix.
“We use and encourage our clients to use inexpensive LiDAR scanners that can be purchased for under $20,000, and can perform field work and work on construction and facilities that were almost impossible to perform in a timely and cost-effective way in the past,” says Gary Outlaw, vice president of Merrick & Company, a geospatial solutions provider.
These portable LiDAR scanners can be mounted on planes or trucks, or they can be used in a ground-based stationary way to scan the contours of a conference room. They are easy to use, and allow surveyors and engineers to plug into their daily fieldwork.
“In the field, these portable LiDAR units can sit on top of a tripod and rotate during data collection so they collect 360-degrees of data. This data can include points below or above the scanner,” Outlaw says.
The speed of data collection is what’s most impressive. “Depending on the size of the LiDAR scanner that you use, the scanner can collect [anywhere] from 10,000 data points per second to over one million,” said Todd Beers, project manager of Merrick's surveying practice. Both photographs and data points can be recorded—with the caveat that LiDAR scanners are point-of-sight systems, so the surveyor or operator has to ensure that everything that he/she needs to record is visible for the scanner.
“Here is a practical example,” Beers says. “Let’s say that you’re working out the configuration of a conference room in an office building. You set the scanner up in the middle of the room, and the scanner’s 360-degree scanning ability will completely capture the data points and the visuals of that room in about three minutes. Keeping line of sight in mind, though, you have to remember to remove chairs, tables and other objects that have the ability to obstruct the LiDAR’s line of sight so you can capture all of the data points that you’ll need for your project….In some cases, this will require that you move the scanner to different locations within the room.”
So how are firms starting to use these portable LiDAR scanners in practice?
“We use them in our own business and we also help our clients use them,” Outlaw says. “Construction and mining companies can use airborne scanners to oversee and measure stockpiles of materials that are out in the field. Building architects can use the scanners in the interior of buildings, perhaps taking a data point representation of an ornate texture that is on a wall of a building they are preserving. In other cases, firms planning to construct a bridge can record fence lines, roads and other elements that the bridge will have to coexist with.”
One of the projects that Merrick has been involved with is the McMurdo Station in Antarctica.
“The facility is extensive, and it would take months to map it all in order do a retrofit of the facility,” Outlaw says. “By using portable LiDAR, a surveyor or construction engineer can expedite the process.”
LiDAR scanners have also benefited the oil and gas industry.
“We’ve known of oil rigs off the Gulf of Mexico where the engineers want to design a retrofit, but they need information at the site that is hard to get,” Beers says. “If they try to use traditional survey technology, it would take them significant time to get this data and the data gathering could be dangerous. By scanning the area with 360-degree LiDAR, and then sending the data to a point cloud, the firm gets a complete set of information.”
The next step for surveyors and engineers is to operationalize the tool.
“There is a learning curve, and we typically see two approaches,” Outlaw says. “If you have the expertise in-house to operate the scanners and to compile the data and analyze it, you can be a self-contained operation. In other cases, companies understand that they might have the surveyors or engineers who can go out and capture the data, but that is all they want to do. In those cases, they can ship their data to a data preparation and analytics company that will harvest the information that they need in order to do a specific project. In either case, an engineering or surveying company doesn’t have to be left behind.”