How Drones Are Used in Construction (Explained for Beginners)

More than 6 years ago I started exploring the drone industry for business purposes and found that I needed to educate myself on all the possibilities.  My first step was a live, in-person seminar that introduced the vast area of drones in construction.  

Since then, I have taken several classes from different media and put the lessons learned into immediate practice.  Although success sometimes seems to come slowly, my persistence and dedication to excellence have provided many successful construction/drone collaborations.

**Being in charge of a construction project is no easy assignment. Construction managers need data from drones to keep track of the site’s progress.  By utilizing drones, construction managers can save time and money, closely monitor safety procedures, maintain supply availability, and keep customers informed and satisfied. **  

Let’s explore how you, the drone pilot in charge, can deliver the product construction supervisors require. 

The connection between drones and construction: the big picture #

Construction sites, no matter how big or small can greatly benefit from the information provided by drone mapping, 3D modeling, and record keeping.  I have flown over projects as small as a single house and as large as a multi-story complex. 

With daily and weekly drone shots, managers are able to keep track of supply inventory.  With orthomosaic mapping in the same configuration each time, the site owner can be shown the progress being made. With a digital copy accessible, questions can be speedily answered by comparing one image to another. 

There are several programs, applications, and companies available to drone pilots that can increase the value of a drone flyover. Skyward, Litchi, and Drone Deploy are just a few of the vast amount of resources a pilot can use.  From the basic planning of the flight to the photographs used for analysis to the data gained, the limitless value to project supervisors is hard to measure.  

The drone pilot can enter an exact path for the drone to take each time they fly.  This gives the same orientation for comparison against each progressive flight. Once the flight pattern has been established, the program automatically takes a photo at the same position.  These photos are processed by the drone provider into an orthomosaic map of the region. 

This map is produced to scale and can actually be placed right over a Google Earth image to allow comparisons to the surroundings.  Additionally, with further processing, a 3D photogrammetry image can be produced.  The site manager can use this image in planning different project phases.   

The use of a drone in construction is far more advantageous than a helicopter or plane.  A drone can fly lower, getting more detailed photographs.  A drone can fly a closer pattern and fly the exact same pattern each time.  Being that each flight is the same, more detailed comparisons are possible.  

Before construction starts #

Drone imagery is extremely important in the planning phase of any construction project.  While it is true that Google Earth images can be used, these images could be years old and not show an accurate depiction of trees and undergrowth or changes that might have been made by water, floods, or other natural occurrences. 

A drone flight is timely, showing the current conditions, and can be executed at a range of altitudes.  The site can be viewed during the flight via the live image feed, and managers can have the pilot shift from place to place to get all the images needed.  

These images can be used to draw in the best paths for utilities to be installed, best sites for electrical mains or wire towers, and contractors can plan for access problems in advance.  

Drones save time, and saving time is saving money #

**One of the major benefits of using drones for construction documentation is that the time necessary to set up and deploy a drone is vastly shorter than traditional aircraft.  **

Faster than manned aircraft #

Flight planning for helicopters and planes involves fuel consumption calculations, airport planning, and having at least two personnel to operate.  The paperwork involved with submitting a flight plan with airport officials can take hours.  

The pilot must drive to the airport where his aircraft is kept, then spend time fueling and preparing for the mission.  Pre-flight checklists have to be done. Like I said, at least two people are needed for the project since the pilot cannot be taking photos at the same time they are flying.  Flying the exact same pattern around a construction site is nearly impossible.  Then there is the return flight to the home base.  All this takes time, and time is money. 

A drone pilot needs only a few minutes to check the airspace availability.  If in restricted airspace, application for permission is done right in the mobile or computer app and approval is only minutes away in most cases.  

All the batteries should be charged before leaving your home or office and the pre-flight checklist for a drone that you carry in a large suitcase is only minutes. The drone pilot drives to the construction site, and the setup and launch take only a few minutes.  

Although there are larger, more complex drones that have a pilot in charge and a person to operate the camera, this is not the usual case at construction sites. The mapping programs take control of the flight path and taking of the photos.  The pilot maintains close observation and can at any time take full manual control of the drone to change the pattern for better shots. 

Save time on walking the site #

A site manager spends a lot of time walking around the project. The image of the supervisor, clipboard in hand, going from place to place is what we all see in our minds when we think of a construction site.  That can amount to hours of time just walking around and checking on where supplies are stacked. 

However, an hour drone flight over the site, in the same pattern at the same time of day can provide a high-quality, digital image on the manager’s tablet or computer.  That image can be expanded or zoomed to provide great detail. The manager can now spend a few minutes focusing in on the particulars and forming strategies to improve the effectiveness of the operation. 

Stockpile measurements and supply efficiency #

The orthomosaic map is to scale, and measurements can be taken of all the aspects of the site. For instance, if a stockpile of drainage pipes is placed on-site, the manager can go to that portion of the image and measure how large the stack is.  A week later, a second image can be compared to see how large the stack is currently, and with the measurements, it can be computed how many of the pipes have been used and when more should be ordered. Think of the time saved in having to go out to the stack and physically count how many pipes are on hand.  

A site manager can take a look at the mapping and see where supplies and materials have been delivered around the site. They can study if the supplies are close enough to where they will be needed and whether workers are spending more time looking for what they need and transporting equipment to a particular spot.  

Drones offer improved safety and hazard identification #

When we think of safety on a construction job site, our main concern is that no one gets injured while working.  The weight and size of the supplies and equipment, and the height of the project can cause catastrophic injuries.  Accidents at construction sites can take away someone’s ability to support their family for many years or even permanently.  

Identifying safety hazards #

Using drone imagery on a daily basis, a manager can quickly identify potential safety issues and prevent the injury of workers before accidents can happen. I have witnessed a supervisor who kept a close eye on consecutive flyover images. He compared photos on his computer screen and was able to zoom in digitally to a junction several feet above the ground.  Seeing the problem, he got on the radio and had a worker correct the issue before anyone got hurt.  

In this case, the problem might not have ever been recognized in time.  The imaging programs available can place the photos side by side so that differences can be seen and then corrected within minutes, thereby improving safety. 

Record of conditions #

Another very big advantage of having digital drone photos is that the construction company has a permanent record of conditions and hazards.  Cases have been recorded where a worker was injured and when investigators came to the site, the supervisor had the capability of showing the condition of the site before and after the incident, proving that all hazards had been mitigated and safety protocols were property in place.  

Search and rescue #

Drones and the images they capture can also be used in live situations, search and rescue, and danger recognition.**  If a collapse of a structure is so precarious as to be unsafe for people to explore, the drone can be launched to provide close-in images**.  Structure integrity can be examined closely while keeping personnel at a safe distance.  Plans can be formulated and material gathered to be able to safely approach a danger zone.  

Certain drones can even carry enhanced devices to aid in search and rescue operations.  A drone can carry and deliver water to a trapped worker who is in an area too hazardous for others to go into.  

Lightweight ropes can be dropped at a location and then the light rope can be used to pull a heavier line until rescue grade cables can be pulled in and attached where needed.  

Thermal image cameras can be mounted on a drone to be flown over a scene and spot trapped workers, or recognize hot spots where fires might be starting or need water and foam to mitigate the potential of further damages. 

Drones can help with keeping the customer happy #

We all know that the primary task of any business is to provide a valued service to your client and make them pleased with the fact that they hired you.  When you have the ability to update your client with accurate, concise reports that demonstrate your progress, the customer will be pleased with the cost of your service and they won’t hesitate to give you repeat business.  

This is especially true in the construction business where projects can run into the millions of dollars.  When the construction company managers can show their progress with side-by-side aerial videos, the client has the opportunity to examine the project up close without actually visiting the site. Even when they might be on the site, being able to view on a tablet current images from an altitude gives an entirely different perspective of the entire site.  

Having digital images means that a construction manager can even send the photos to the client’s office to view in a board room or conference center for all the stakeholders to peruse. 

A client called me awhile ago to look at the inside of his factory.  This very experienced manager had recently been brought on board to modernized the production line and what he found greatly upset him.  He was having a hard time explaining by conference phone calls to the foreign owners the necessary changes that had to be made to the factory.  

His first solution was to rent a power lift and stand on the raised platform while someone drove the lift around the factory floor. He quickly recognized the drawbacks of this operation.  The platform, while in the air, was unstable while moving, and it was hard to change locations to get just the views he wanted.  Additionally, since the factory floor was taken up with supplies, machines, and materials, the lift operator could not get to every point in the factory. 

I launched my drone and while the manager was viewing the flight with live view goggles, he was able to tell me the exact shots he wanted.  I completed the flight, recording video and taking photos at the same time.  My product was delivered the next day directly to the conference room and shared with the factory owners in Japan.  

The manager was ecstatic with the results and the owners immediately authorized everything he wanted.  My flight took a quarter of the time that it would have taken to drive the lift around the whole factory and the images were exactly what was needed. 

All this was possible because the manager could view in live time and communicate any changes needed. I cannot tell you how many repeat appointments and referrals I have received from this mission. 

Drone operations decision point #

A decision that must be considered at this point is, does the construction company want to operate its own drone fleet or hire outside drone service to provide the service. 

Putting together a new drone operation can be very costly and time-consuming. One of the first things to consider is what kind of drone will fit your needs. So, what are some of the drones that can be used in construction? There is no best answer to this question. 

Factors that need to be weighed are the budget, scale of the project, and what tasks need to be accomplished.  There are a number of drones that stand out and construction companies that are thinking of running a drone program for their projects should study several before investing in them.

Fixed-wing or multi-copter? #

There are two different platforms of drones for construction. There is the fixed-wing version and the multi-copter version. Fixed-wing drones are generally more expensive and have fewer options but offer extended flight times per battery and can therefore cover very large and expansive areas. A multi-copter drone is more maneuverable and can carry a multitude of payloads but have shorter air time and have trouble in inclement weather. 

Two examples of fixed-wing drones that are popular for construction projects are the WingtraOne drone and eBee X by Sensefly. 

WingtraOne #

The WingtraOne is actually a VTOL (vertical take-off and landing) drone. The WingtraOne is a good choice for large-scale construction projects thanks to its estimated 55 minute flight time. The drone can cover hundreds of acres in a day and comes with a 42MP full-frame Sony camera. 

The drone comes with a PPK (post-processing kinematic) receiver that can achieve extreme accuracy. And with its IP67 and military-grade rating, it can be flown in harsh weather conditions.

eBee X #

The other option for a fixed-wing drone is SenseFly’s eBee X. This is another good choice for large-scale construction projects. The standard flight time is reported to be 55 minutes and can be extended to 90 minutes with their “endurance extension plan”. 

The drone is compatible with multiple cameras including the Aeria X camera with its APS-C 24MP sensor and the S.O.D.A 3D mapping camera.  

Multi-copter drones include a number of options many of which are from DJI,  the leading drone company worldwide.

Phantom 4 Pro RTK #

One of the most popular drones for construction purposes is the Phantom 4 RTK (real-time kinematic).  The drone comes with many advanced features which include its internal RTK receiver that can achieve centimeter-level accuracy from low altitude. 

The camera has a 1-inch sensor and captures 20MP images. These aerial images can be transformed into 2D orthomosaic maps and 3D models. The drone has omnidirectional obstacle avoidance sensors for safer flying and has a flight time of about 30 minutes.

DJI Matric 300 RTK #

The DJI Matrice 300 RTK is an advanced technology drone and comes with a maximum flight time of 55 minutes. It’s a well-built drone with a rugged design that allows it to be operated in all kinds of weather conditions. It comes with multiple payload capabilities and is compatible with DJI’s new L1 LiDAR sensor.

Mavic 2 Enterprise #

A couple of other drones from DJI suitable for the construction industry include the Mavic 2 Enterprise which comes with a dual-camera. One is an RGB camera that has a 1/2.3 inch sensor the other is a thermal camera. 

Mavic 2 Pro/Zoom and Inspire 2 #

There are also the Mavic 2 Pro and Zoom and the Inspire 2, all of which come with high-quality cameras that can be used for things like inspections and mapping.

Microdrones #

A good alternative to DJI is microdrones. This company manufactures its own range of commercial drones. Their drones can be equipped with LiDAR sensors or a professional camera like the Sony XR1R II.  The average flight time of each of their drones is around 40 minutes and they are built to be operated in the harshest of weather conditions.  

Autel Evo II, Parrot Anafi, Skydio 2 #

Other multi-copter drones that are suitable for commercial use include the Autel Evo 2 RTK series, the Parrot Anafi dual-camera drone, which is more suitable for inspection thanks to its thermal camera and the Skydio 2 drone.

Professional drone pilots: in-house or outsource? #

Any construction company that is starting an in-house drone program would also need to train pilots for their drones.  The United States FAA has a certification process and requires that all drone pilots that fly for commercial purposes have to have a current Part 107 certificate.

Using an established drone service that already has the proper equipment, certified personnel, and experience in construction site missions can be highly advantageous and cost much less, at least in the beginning phases.   

The use of drones in the construction industry is growing, as it is a relatively new technology. What is clear is that those companies that are using drones to survey and map their construction sites have seen significant improvement to their operational efficiency and also helped improve worksite safety and reduce costs. 

Using the process of capturing aerial images and data, which is much easier and faster, allows for improved decision making, mitigating issues as soon as they are identified, and helping to keep projects on schedule and save costs.

References:Microdrones