'Air Taxi and Drone Delivery' Era Approaches... Will the Increasingly Crowded Skies Be Safe? [Reading Science]

Unmanned Aerial Vehicle Traffic Management System - Active Development of AI Autonomous Flight Technology
South Korea and Major Countries Expected to Commercialize Within 5 Years
Ultra-Precise GPS Technology Enables Navigation Like Human Eyes, Avoiding Obstacles

On the 11th, Volocopter is conducting a test flight at the 'Urban Air Mobility (UAM) Flight Demonstration Event' held at the Gimpo Business Aviation Center (SGBAC) in Seoul. Urban Air Mobility is a new air transportation system that operates in connection with other transportation modes for the purpose of transporting passengers or cargo, using eco-friendly electric vertical take-off and landing vehicles that can be utilized within urban areas. Photo by Moon Honam munonam@

[Asia Economy Reporter Kim Bong-su] The 1997 sci-fi film "The Fifth Element" provided many hints about the future of humanity brought by advances in science and technology. One of these was the "flying" cars. The manned and unmanned flying cars that freely navigated through the maze-like complex skyscrapers in the movie stimulated the imagination of audiences at the time. Now, 25 years later, just like in the film, with the increasing vertical development of cities, urban air mobility (UAM) and unmanned drones are actively being developed as cargo and passenger transportation means. However, the most crucial factor for commercialization is "safety." Even ground vehicles cause significant damage when accidents occur. If drones flying in the sky fall, not only can the passengers be injured or killed, but secondary damages such as destruction of facilities and casualties at the crash site are even more frightening. Therefore, active research is underway to develop technologies that ensure safe transportation without collisions or crashes, even when hundreds of drones fly concentratedly in a specific area. South Korea is also conducting full-scale research and development on unmanned aerial vehicle traffic control technology (UTM) and AI autonomous flight functions for safe drone flight.

Damian Hischier, a test pilot, is posing for the press after completing an on-site flight of the Volocopter at the Urban Air Mobility (UAM) flight demonstration event held on the 11th at the Seoul Gimpo Business Aviation Center (SGBAC). / Photo by Moon Honam munonam@

◇ Full-scale Research on Low-altitude Air Traffic Management Systems Begins

There are rules even on the roads we casually drive on. Speeds above a certain limit are prohibited, and rules regarding road width and vehicle spacing must be followed. Likewise, airplanes flying in the "empty" sky are subject to similar regulations. Urban unmanned aerial vehicles, which inevitably cluster in the low altitude range around 150 meters above ground, require even stricter regulation and control. Safety devices such as centimeter-level precise positioning, route tracking, collision avoidance, and continuous communication connection guarantees are essential.

Unmanned aerial vehicles are likely to operate autonomously at altitudes below 150 meters, where manned aircraft operations are prohibited. The big challenge is how to ensure free flight and safety of both the aircraft and ground facilities in these densely built low-altitude areas. To solve this challenge, UTM technology is being developed. In places like NASA in the United States, where drone delivery has already started, traffic control technology has been developed that allows hundreds of drones to operate simultaneously in a specific area without issues. In South Korea, the Korea Aerospace Research Institute (KARI) has been developing precise integrated navigation, security, and communication technologies since 2017 under the project titled "Development of Core Technologies for Security and Unmanned Aerial Vehicles for UTM Systems." Although it sounds simple, experts say it is a highly challenging task to process an enormous amount of verified data and make accurate decisions while dozens to hundreds of drones are operating simultaneously.

In October last year, KARI succeeded in an experiment operating eight drones simultaneously at low and high speeds while performing delivery missions. Currently, they are testing a web-based ground control system (GCS) capable of simultaneously managing 30 to 100 drones. This system exchanges data with flying drones once every second to display location and status information on the web. Each drone is remotely managed to take off, hover, or fly automatically to pick up items from a logistics warehouse and deliver them to the destination for landing. The system precisely detects the positions of the drones to maintain spacing, verifies how well drones respond to commands when far from the control center, ensures clean communication, and checks for risks of hacking or flight information theft. Due to various weather changes such as snow, rain, and wind, more verification is still needed. Dr. Bae Jung-won of KARI's UAV Research Department said, "We are developing UTM technology that helps companies' businesses and providing various services supporting safe flight. UTM can also help resolve grievances of stakeholders and clarify responsibilities in case of accidents. Along with improving UAV endurance and safety technologies, the development of UTM services must also progress."

◇ Safe Even When GPS is Lost

What happens if a drone's GPS malfunctions or communication is lost during flight? To prepare for such cases, technologies are being researched to enable unmanned aerial vehicles to fly safely by themselves, avoiding buildings and people, supplementing existing GPS. A notable domestic technology is the 3D semantic mapping and surrounding environment recognition technology using deep neural network technology developed by Professor Kim Sang-hyun's team at Cheongju University’s Department of Aeronautics. GPS signals can be risky in urban areas with many signal interferences and distortions, especially near skyscrapers. The core idea is to apply deep neural networks, a type of artificial intelligence, so that unmanned aerial vehicles can recognize their surroundings similarly to humans, allowing safe flight even if GPS is lost in the "urban canyon."

Professor Kim explained, "We are developing deep neural network-based object and environment recognition technology to process real-time images obtained from cameras mounted on unmanned aerial vehicles. Using this, we aim to create 3D semantic spatial maps and sensor fusion-based 3D precise positioning so that UAVs can autonomously refer to map information and find safe routes for flight." However, unlike cars, drones must be miniaturized and lightweight, so developing algorithms that operate effectively on limited hardware is a challenge. Another factor slowing research progress domestically is the many no-fly zones, which restrict free drone flights.

◇ Commercialization Already Near Overseas

The United States, which has already commercialized drone delivery such as pizza delivery, is moving swiftly. Last year, it established regulations mandating remote identification devices on drones, to be fully enforced from next year. All drones over 250 kg are required to have remote ID attached. The Federal Aviation Administration (FAA) and NASA are jointly conducting pilot and demonstration projects for UTM technology development. The U.S. is developing a UTM pilot program in the first phase, researching and developing systems such as flight plan sharing among operators and flight information management systems (FIMS) usable by UAS service suppliers (USS). In the second phase, to activate the UTM ecosystem, remote ID recognition technology (RID) will be distributed to UAS service providers such as Airbus, Amazon, Intel, OneSky, and Skyward. They also plan to upgrade this to provide safer and more efficient UTM services through a "UTM Field Test Project."

The European Union (EU) also implemented the "European Drone Rules" in January 2021, established by the European Union Aviation Safety Agency (EASA), applying to all EU member states as well as non-member countries such as the UK, Norway, Iceland, and Liechtenstein. The rules cover drone size, output, type, performance, technical requirements, flight safety conditions, drone identification, prior approval requirements, and pilot training. Currently, drone flight altitude is limited to 120 meters, and operation in densely populated areas is prohibited. All drones must be certified and registered, with registration numbers displayed. EASA is also implementing the "Drone Strategy 2.0 Policy," including strengthened cooperation between civil and airspace industries since October last year. The EU has been actively developing UTM since 2017, establishing the "U-space blueprint" roadmap in four stages to create an unmanned aerial vehicle flight environment. The EU, Eurocontrol, and companies are each investing one-third of a total 1.6 billion euros to build UTM services by 2024.

Japan launched the public-private JUTM project in May 2017 to develop UTM, aiming to implement the completed program between 2020 and 2030. Under the Ministry of Land, Infrastructure, Transport and Tourism, the DRESS project was promoted until last year to develop drones and robots for logistics, infrastructure inspection, and disaster response, as well as systems for social implementation and flight testing. China has also been intensively fostering drone development at the government level, enacting the world's first small drone operation regulations in December 2015. In 2016, the Civil Aviation Administration of China enacted related laws to strengthen unmanned aerial vehicle management. In 2017, it mandated real-name registration and management for all unmanned drones over 2.5 kg.

Dr. Bae said, "Compared to overseas, South Korea has one of the world's best wired and wireless network infrastructures, and we are actively adopting and researching the use of the well-established LTE network for remote identification and location reporting (Remote ID). This is excellent technology that can cover both visual line-of-sight and beyond visual line-of-sight flights." He added, "It is necessary to clearly define the roles and authorities of stakeholders through laws and regulations, and to resolve issues such as the dual system of video recording and flight permission."