For Nathan Scrivener, Quality Control Director for Reliable Contracting Inc., of Odenton, MD, stockpile measurement has become a monthly operation rather than a quarterly one. That is because in October 2016, the company purchased a DJI Phantom 4 Pro professional drone to perform that task. Coupled with “Map Pilot” software, Scrivener said the once-tedious task of determining stockpile quantities has become a simple, clear-weather-day project.
“We went from manually measuring stockpile inventories on a quarterly basis to hiring a drone measurement company to take those inventories for us,” he said. “After a time of seeing how well that technology works and by seeing how easy it was to fly the equipment, we decided to purchase our own equipment. Our sister company, Environmental Quality Resources (EQR), had been using drone technology for some time doing work with it on as-built construction projects. They do a lot of retention ponds and green space building projects. They use the drone technology especially to build ponds. They would fly a grid and get a 3-D map of what the pond would be.”
“They upgraded from a Phantom 2 to a DJI Inspire Pro. The Inspire Pro model has a better GPS system, with better stability and wind control. It also has a higher quality camera set up, which gives them more options for flying. Unless it is raining, they can use their drone in almost any weather.”
“So, based on their success, we went ahead with a DJI Phantom 4 Pro,” Scrivener said. While EQR was using software that helped them map out retention pond parameters at jobsites, the software that Scrivener chose was designed for open space stockpile measurements. “All I have to do is program into the system where I want the drone to do its measurements, and it does the rest. It flies over the site in a grid pattern and returns when the job is complete. We have been extremely happy with our results. It was an extremely cost-effective purchase. Even with having to purchase our own equipment, liability insurance, FAA permitting and other related costs, it costs us less than doing it the other ways.”
Phantom 4 Pro capabilities
According to DJI’s online product information, the Phantom 4 Pro drone is an entry-level, professional drone, equipped with an obstacle avoidance system that make flying the drone safer and more error-free. Scrivener said that his previous experience as a youngster, playing with remote-controlled helicopters, made flying the Phantom 4, easy to do. With only two joysticks needed to manually fly the machine, it didn’t take Scrivener long to fly the drone successfully. “There was very little in the way of a learning curve,” he said.
This model drone weighs slightly more than three pounds with battery and propellers, and is able to fly for up to 30 minutes on one battery charge. Having multiple charged batteries at the jobsite will increase the overall flying time when visiting a project. The 20-megapixel video camera is capable of 4K, video recording with 60p resolution. The sophistication of this model offers forward, backward and downward vision capabilities. Additionally, it can sense objects front and rear and left or right using its infrared obstacle avoidance system.
Not only can the Phantom 4 Pro store video and still photos in its onboard storage, but it is also able to transmit those images back to the operator at a distance just over 4 miles, using the Lightbridge system. These images can be viewed in “real time” via Wi-Fi connection to either a smart phone or electronic tablet, equipped with the appropriate apps.
Scrivener said he sometimes takes photos of jobsite projects, depending on their location. If he is too close to a nearby airport, he is not able to fly the drone without permission from the FAA. He also uses it from time to time to take photos for promotional items or company video archives.
He added that he is looking forward to seeing how this technology improves and develops over time. He said that he would be interested to see how combining their existing mapping technology with technology from Trimble Company, a GPS company with whom they are already doing business. Scrivener believes that combining the two systems, could improve the usefulness of drones. He is looking forward to not only measuring specific sites or stockpiles, but also attaching that information to specific ground control points. He said that surveying for site layout and plant design capability would be a helpful tool as that software becomes available in the future.