Technology is promising.
Digital pairing is to make full use of data such as physical model, sensor update and operation history. In order to integrate the multi-disciplinary, multi-physical, multi-scale and multi-probability simulation process and complete the mapping in the virtual space, thus reflecting the whole life cycle process of the corresponding physical equipment. In layman's terms, digital twinning is to create a digital version by collecting various data on the basis of a device or system.
"At present, the application of the digital twin system in the civil aviation industry is mostly based on three-dimensional geographic information, and it is still in the static digital twin stage, and the data update frequency is low. Its main functions are information integration and data visualization. " Yang Jie said, "The next step will be to realize dynamic digital pairing. Taking this technology as the carrier, the data of airport and aircraft are integrated. After the accessed data is displayed visually, the physical world will be controlled reversely by twins, so as to achieve the purpose of process control. In the future, it is also possible to combine technologies such as 5G, artificial intelligence and ubiquitous sensing to achieve precise control. "
In digital pairing technology, one system exists in the real physical world and the other system exists in the virtual computer world. In an ideal state, ontology and twins can establish comprehensive real-time or quasi-real-time contact. The two are not completely independent, and the mapping relationship is real-time and bidirectional. According to the information fed back by twins, take further action and implement intervention. Taking aircraft maintenance as an example, the model of real aircraft is established in digital space, which is completely synchronized with the real state of aircraft through sensors. After each flight, according to the structural situation and previous load, timely analyze and evaluate whether it needs maintenance and whether it can bear the load of the next mission.
"Aircraft maintenance is just a point in the digital twins. When they are connected, they will form a face. At present, many domestic airports have launched full-motion video systems, through which the real-time situation of airport scenes can be seen in the tower or operation command center. However, in bad weather such as rain, snow and smog, some cameras are blocked, which may have an impact on the monitoring of key dynamic targets. After the application of the digital dual system, the real-time data collection through sensors can reflect the operation of the target and provide more accurate information for the staff, thus improving the operational support ability. In the future, with the development of technology, points will be connected into faces and faces will be connected with adults. The traditional pyramid structure will no longer exist, the Internet of Everything will become a reality, and perception will be everywhere. Digital twin technology will have more room to play. " Yang Jie said.
At present, most airports still rely on the terminal platform to make decisions when performing tasks. For example, when the vehicle breaks into the runway, the tower staff need to command the aircraft and the vehicle separately to achieve the purpose of avoiding. In the future, sensors will be deployed on airplanes and vehicles, and two different types of terminals can obtain each other's data. Once there is a risk of runway incursion, through edge calculation, the digital twin system will directly inform the driver of the vehicle to avoid and provide an evacuation route, with fast response speed and high safety factor, and the millisecond alarm response time eliminates the potential safety hazard caused by delay.
Have a research and development foundation.
At the beginning of this year, the Civil Aviation Administration issued a roadmap for the construction of smart civil aviation, which divided the overall design of smart civil aviation into five main tasks, four core tasks, three types of industrial cooperation, ten supporting elements and 48 scene viewpoints. The construction of smart civil aviation needs the development and application of digital pairing technology, with the pilot projects of convenient travel in the whole process, refined operation based on four-dimensional flight path, coordinated operation of the whole airport, and data-driven industry supervision as the starting point, so as to help industrial synergy and show its talents in the construction of smart civil aviation.
High-rise buildings do not rise out of thin air, and so does the research and development of technology. Since 20 13, the institute of aeronautics and astronautics has started to establish an ADS-B ground station, and the data collected by ADS-B is of great benefit to the application of digital twinning technology. In addition, Guangzhou Baiyun Airport, Shenzhen Baoan Airport and other airport scene flight area vehicle monitoring systems, Air China, Sichuan Airlines and other global flight tracking monitoring systems have not only accumulated rich experience for aircraft tracking monitoring and vehicle tracking monitoring, but also laid a solid foundation for the development and application of digital twin technology.
The arrival of the 5G era makes digital pairing technology like a duck to water. The Internet of Everything makes data transmission faster and faster, and sensors and cameras can be seen everywhere, which can capture more and more details. The traditional airport operation control system based on three-dimensional geographic information can no longer meet the needs of the times. It is understood that the development of data twinning technology in the Academy of Aeronautics and Astronautics takes the game engine as the carrier. After accessing relevant data, not only data integration and visualization can be realized, but also the system can run more smoothly. The key information of the twin world and the real world is synchronous and consistent at the level of sensory experience.
At present, the development and application of digital twin technology is still in the stage of information integration and data visualization, but it has brought great influence to the operation of airports and aircraft. The dynamic digital twinning technology will touch all processes of the civil aviation industry and improve the efficiency and empowerment of each process.
Based on digital pairing, real-time pairing images can be generated from airport, personnel, aircraft, vehicles and other data, making personnel training more convenient. Vehicle drivers no longer need to walk into the classroom with teaching materials to learn airport driving rules, but learn in the real-time running scene of the system; Driverless driving will be smarter. Equipment and vehicles will be tested by the digital twin system first, and then formally mass-produced and applied, thus minimizing the cost. ...
Data is the key
The more complete the data collection, the more data that can be analyzed in real time, and the closer it is to the real situation. On the one hand, the data collected by technologies such as ADS-B and digital twin are complementary, but each technology has a tendency to be used, and collecting data has limitations. The data transmitted by ADS-B is limited to aircraft position, altitude, heading, speed, climb rate, etc. The original intention of this technology is more inclined to air traffic control, but it is impossible to obtain data such as fuel quantity, engine parameters and flight management computer output information, and the data needs multi-interface access. On the other hand, the data collection in the real world has not been fully covered, cameras and sensors are increasing with the development of the times, and the number of access facilities and equipment will gradually increase. In addition, real-time collection of people's location data involves many issues such as privacy and needs to be treated with more caution.
"The key indicators of spatial data acquisition are accuracy and acquisition frequency. In the GPS system and the Beidou satellite system that is gradually put into use, the position accuracy and positioning accuracy can reach decimeter or even centimeter level, which can meet most of the needs of the airport in operation. " Yang Jie said, "But the main shackle of technological development lies in the frequency of location regression. Although the current technology can reach the standard of 20 Hz, that is, 20 times of data information is returned every second, many airports still stay in the state of returning once every second and returning once every few seconds. "
The data transmission frequency between traditional radar monitoring and data station monitoring is quite different, ranging from once every 4 seconds to once every 15 minutes, which cannot reflect the real world in real time. After installing ADS-B, the data can be transmitted back to 1 s twice at the earliest, but it is still far from the technical ability of 20 Hz.
"Domestic airports basically don't need 20 Hz, and few can reach 5 Hz. The higher the backhaul frequency, the greater the network bandwidth consumed, and the greater the processing pressure of the background processor. From this perspective, if you want digital twin technology to play a greater role, you must first solve these problems. " Yang Jie explained.
Only by dealing with the problems of data collection, return frequency, accuracy and processing, can digital twin technology really contribute to the construction of smart airport, rather than providing a "vase" for data visualization platform. This information technology is organically integrated with traditional infrastructure, with cloud computing, big data, Internet of Things, artificial intelligence and 5G communication as the core means to promote the high-quality development and leap-forward progress of China's airports.