Embry-Riddle Aeronautical University and Gaetz Aerospace Institute studying the effects of urban landscapes on drones.
Urban Air Mobility (UAM) represents a new era in air transportation. A community of government, industry and academic partners is working together to research the practicalities before UAM is declared fully viable in populated areas. The goal is to develop a safe and efficient air transportation system where everything from small package delivery drones to passenger-carrying air taxis is able to operate over towns and cities.
Whereas drones are already being used in relatively unpopulated parts of the world, cities offer a very different terrain. The effect of ‘urban canyons’, such as building-lined streets, needs to be fully understood. For example, as the breeze is funneled into the relatively narrow gap between buildings, wind speed can increase dramatically, and the heat from city surface temperatures can produce unexpected thermals.
To study the effects of urban landscapes on drones, a team from Embry-Riddle Aeronautical University and Gaetz Aerospace Institute took off to Kosovo. The team knew it would have been extremely difficult to get permission to fly in a built-up, densely populated area in the US. Kosovo was identified as a potential location for testing as many of its urban environments are sparsely populated due to the war in the 1990s.
The team flew a small unmanned aerial vehicle (UAV) rigged with special instrumentation, including two FT205 sensors which were mounted orthogonally so as to measure both horizontal and vertical wind fluctuations. The eight-motor ‘octocopter’ drone (a DJI S1000) also measured the temperature, humidity and air pressure in two cities – Janjeva and Prishtina. Combining the wind speed, direction and temperature information gained from the anemometers with aerial photos taken by the drones, the team were able to generate 3D models showing 3D wind components.
With the help of the FT205 sensors, the team was able to measure the wind turbulence in an urban canopy. This will be hugely helpful to companies looking into urban air mobility as it will help them better understand the environment their aircraft will be placed in.
“Within the atmospheric ‘boundary layer’ in cities, the wind constantly shifts as it flows over hot asphalt, followed by cooler green spaces, water-filled canals, and structures of various shapes and sizes. To map those unseen changes, researchers have traditionally simulated urban environments in wind tunnels or with computer models. For the first time, Embry-Riddle faculty and students have captured real-world data to create a three-dimensional map of drone routes.
“Nobody else has been studying the urban atmospheric boundary layer in this particular way. Many companies are now working on drone-based package delivery, infrastructure inspection and urban air mobility. We need a better understanding of airflows and microclimates in cities so that these new technologies can operate as safely as possible.
“We were able to make multiple urban boundary layer measurements, right smack downtown in Prishtina, in an urban canyon with 14-story buildings on either side.
“The FT205 wind sensors were perfect for our operations. Their light weight and accurate measurement contributed immensely to the success of the project. The sensors have been on the road, traveled halfway round the world and back again, and have stood up well!”
Dr Kevin Adkins
Associate Professor of Aeronautical Science
Embry-Riddle Aeronautical University