Drones are Thriving in Some Areas of Surveying
Drone news splashes have regularly appeared in 2017, but if you're in the surveying and mapping disciplines, you probably already know that drone technology is still evolving at your company, and that current regulatory limitations constrain drones from being used to their full potential.
Despite this, it isn't too early to think about how your firm could use drones.
Where Drones are Thriving
In surveying and mapping, drones are being used for operations in smaller areas, where there are physical barriers that discourage on-the-ground surveys. Drones are also being used to inspect and monitor infrastructure assets like utility towers, and to perform volume estimates of piles of coal.
"Surveyors and mappers are realizing that unmanned aerial systems (UAS) are a versatile and powerful new platform for surveying and remote sensing instruments, including digital cameras, LiDAR and multispectral sensors," says Karen Schuckman, assistant teaching professor at Penn State University and program manager of the American Society of Photogrammetry and Remote Sensing (ASPRS). "They bridge an important gap between ground-based static and mobile mapping systems, and traditional fixed-wing and rotary-wing airborne platforms. Very large-scale imagery can be quickly collected over smaller areas of interest at relatively low cost; final products can be generated in a matter of days or even hours."
She says that drones excel in any application requiring detailed 3D mapping over a small area.
"For example, stockpiles, archaeological sites, industrial facilities, bridges and dams," she says. "UAS mapping is also showing promise in resource management applications, such as mining, forestry and agriculture. Finally, UAS provides the means to map sites that are in some way hazardous or inaccessible, yet need more detailed mapping than a conventional airborne survey can provide."
It is equally important to mention that drones must operate under tight regulatory constraints.
"Drone technology is extremely advanced, beyond the functions that drones are being used for today," says Mike Tully, CEO of Aerial services Inc. "For instance, drones can fly great distances over lightly populated areas, but they are limited by regulatory constraints that require them to operate within 400 feet of the ground and within line of sight."
Surveyors and mappers must consider the regulatory constraints on drones, and where it is more appropriate to use an aircraft equipped with LiDAR in a project.
In spite of regulatory limitations, the value of drones for companies in increasing with the awareness of the applications where they can be used.
"A drone is just a means of getting a payload of sensors in the air to assist with mapping such as capturing of photographic images," says Christian Stallings, R&D manager at McKim & Creed. "The data collected can be processed into a point cloud, which enables surveyors and mappers to work with it. ... Going forward, the size of sensor payloads are continuing to expand, as well as the reliability of systems. Drones will be able to do more."
The Achilles Heels of Drones
In addition to the potential in drones that is only limited by regulations, there are shortfalls in drone technology that need to be addressed.
"It is still difficult to replicate the geometric and radiometric precision of instruments widely used in geospatial projects today," Schuckman says. "Costly GNSS/INS direct georeferencing systems are required to produce accurate 3D point clouds from LiDAR, for example. Cameras and multi/hyperspectral sensors small enough to fly on a UAS and inexpensive enough to risk a 'hard landing' are not as stable and are more difficult to calibrate."
Tully has concerns about security.
"The security area has not been a focus for drone manufacturers, so what we are finding is that drones are not sufficiently hardened to protect them from jamming, interference, crashes and hijacking," Tully says. "Because this area is still evolving, insurance companies also hesitate when it comes to developing liability insurance."
Schuckman also cautions against expecting too much from drones.
"Drones can't do everything," she says. "While drones fill in some crucial gaps in geospatial data acquisition, they are still one tool in a very big toolbox. They are not suitable for mapping large areas such as citywide, countrywide, statewide and nationwide mapping programs that are the mainstay of geospatial data for most end users. What drones do provide are high-resolution, quick updates over small areas. They cannot and likely never will be the platform of choice for important products like seamless high-resolution elevation models or land cover datasets."
It is also important to remember constraints on drones that require them to be battery-operated. Since batter life is limited, realistic drone airtime might only be 15 or 20 minutes.
Weighing the Adoption of Drones
There are pros and cons to investing in drones for geospatial work.
First, the pros:
The rapid development of robust data processing tools that support product generation is invaluable, according to Schuckman. "Our ability to create realistic and accurate 3D models of almost anything using UAS-acquired data opens up many new opportunities for surveyors and mappers who are willing to make the investment in equipment and education."
Stallings says that topographic map development is a good application for drones because more data can be collected with greater accuracy. Many McKim & Creed clients report operational cost reductions of 30 to 70 percent when they use drones. "The time to develop a topo map is also reduced, although you must use the drone over cleared land, not land with cover. This makes drones ideal for cleared areas like building sites or farm fields."
Cons of adoption:
UAS mapping automation and relatively low cost of entry make it easy for "the blissfully unaware" to create a bad product, Schuckman says. "The FAA has exerted some control over the training and qualification of drone pilots. However, anyone can make, and presumably sell, a drone-derived map. The issues of professionalism, proper training, industry certification, and even professional licensure have been around and hotly debated in the geospatial industry for decades. Is 'buyer-beware' a sufficient barrier to the proliferation of 'bad' data?"
Shuckman explains that many geospatial data consumers, particularly public agencies, have traditionally relied on the professionalism and proven qualifications of their vendors. It is imperative that newcomers to surveying and mapping respect the level of education, training and experience required of a true geospatial professional.
"Drone adoption has certainly encountered its speed bumps," Stallings says. "Regulations are still maturing at the state and federal levels, although they are settling down. Manufacturers, too, are still struggling with how to standardize hardware and software that address applications like mapping."
Finally, the understanding of drones within geospatial companies must be further developed.
"More technology training and educational awareness of drones in the surveying and mapping sector will definitely help," Tully says. "There are many surveyors who haven't had experience with remote sensing and data capture gear, and who might not understand the principles and techniques of mapping in this environment when it comes to assuring positional accuracy. There are accuracy standards that need to be achieved, and training is needed so that surveyors have the necessary background."
Tully says that determining the accuracy of a map is a function of all of the components of a drone's operating system, not just what a sensor or a camera transmits. "Many drones come with extremely accurate cameras, but unless an individual is able to manage operations through the system on the drone, it can be hard to achieve the outcomes that you want. You need to understand the drone's management system well enough to work with it."
Drones: Something to Consider
Although drones are still an emerging technology for surveyors and mappers, and they can't compete with aircraft and LiDAR in every situation, it isn't too early to think about where they can be deployed to improve operations.
"I would encourage experienced GIS mappers, seasoned surveyors and newcomers alike to seek out high-quality educational resources to accelerate their entry into the world of UAS mapping," Schuckman says. "There are man new developments that challenge even those of us who have years of experience and solid geospatial fundamental knowledge. Many universities are offering for-credit and short courses in UAS mapping, and organizations like ASPRS provide guidance in the form of workshops, symposia and standards development. Aspiring UAS mappers should seek out these resources to help build a strong, credible resume and assure their ultimate success."