The Khalifa University team explain the fog drone to Vice President and Prime Minister of the UAE, Mohammed bin Rashid Al Maktoum.
A team of three PhD students from the Sharjah campus of Khalifa University may have found a method of solving a perennial problem for the region’s aviation industry. And in the process, they could also have identified a new application for unmanned aircraft.
“We wanted something really innovative,” Sameera Adulrahman Almulla told ShowNewsduring last month’s Commercial UAV Show in London. “Ninety percent of the projects are based on image processing. It’s rare that any of these drones are used for something that I believe is more innovative.”
Sameera and her colleagues came up with the idea of using a small UAV for fog mitigation after deciding to enter the UAE government’s ‘Drones for Good’ competition. The initial use they envisaged was to clear fog on Emirati roads. After investigating the economic impact of fog on airport operations, the team extended their plan to a mitigation system that could work for runways.
“It took around four to five months to understand the fog and how we can dissipate it,” Sameera says. Dry ice can dissipate cold fogs, but the UAE’s warm fogs required a different approach. The team hit upon the idea of using a 6% brine solution, which—while its potential impact on the maintainability of aircraft and runways remains untested—is a more environmentally responsible alternative to a chemical-based dissipation agent.
“We had several challenges,” says Sameera. “We had the challenge of using drones, we had the challenge to spray our solution with the very limited power that we have on the drone, and we had another challenge in that we wanted to test our approach and the fog is a natural phenomenon—so we needed to create a fog and we needed to use the drone to spray and to check our concept. Could it get the results that we are aiming for?”
A small rotary UAV—the Typhoon quadcopter—was selected as the delivery mechanism. The 10kg aircraft is capable of carrying a 40kg payload of brine solution, though a key issue that needed to be overcome was maintaining stability in flight with a liquid payload. Work on flight control was carried out by the supplier, the Dubai-based design and distribution company Ultimate UAV, which partnered with the students for the competition.
According to their tests, the team found that spraying 3.5ml of solution would clear one cubic metre of fog. They built a fog chamber and found that within 20 minutes, fog can be dispersed sufficiently to improve visibility by 95%. To deliver this performance over a larger area would require several aircraft working together. “We would divide the runway into three layers, and would need about seven drones to clear it in 20 minutes,” says Sameera’s colleague, Khawla Abdulla Alghafli.
The concept of using the UAV to clear an artificially created fog was proven with a flight during the competition. There have been no further tests, though Etihad Airways has had initial discussions with the team that may lead to further work. Etihad’s hub, at Abu Dhabi, is particularly susceptible to fog.