The automatic driving system possesses functions such as automatic train wake-up and start-up, automatic entry and exit from the parking lot, automatic cleaning, automatic driving, automatic parking, automatic door opening and closing, and automatic fault recovery. It also has multiple operating modes, including normal operation, degraded operation, and operation interruption. Achieving fully automated operation can save energy and optimize the reasonable matching of system energy consumption and speed.
Automated driving systems require urban rail transit systems to achieve high levels of interconnectivity, safety, speed, and comfort. Since the 1990s, with the development of communication, control, and network technologies, high-capacity, two-way information transmission between trains and subways has become possible, making it possible for high-density, high-capacity subway systems to become truly automated driving systems.
Functions of autonomous driving systems
The main functions of the automatic driving system are two-way information transmission between the train and the ground, and the integration of operational organization and emergency response. The train-to-ground information transmission channel is an important component of the automatic train control system. The onboard equipment of the automatic control system relies entirely on the train control commands received from the ground control center to drive the train, monitor the actual speed of the train and the speed commands allowed by the ground in real time. When the train speed exceeds the ground speed limit, the onboard equipment will apply the brakes to ensure the safe operation of the train.
The automatic driving system enables the train to start and run automatically, stop at designated stations, turn around automatically in fully automated driving mode, and enter and exit the depot automatically. At the same time, it monitors and detects the status of passengers, carriages, and equipment on the train, performs automatic diagnosis of various train systems, transmits the status of train equipment and fault alarm information to the control center, and classifies various faults and unexpected situations to make contingency plans.
Key technologies of autonomous driving systems
Autonomous driving systems are comprehensive systems that integrate numerous advanced technologies. Key components such as environmental information acquisition and intelligent decision-making and control rely on innovation and breakthroughs in sensor technology, image recognition technology, electronic and computer technology, and control technology. For driverless cars to achieve significant development, breakthroughs and innovations in multiple technologies are essential.
Key technologies related to autonomous driving systems include environmental perception, logical reasoning and decision-making, motion control, and processor performance. With advancements in machine vision (such as 3D camera technology), pattern recognition software (such as optical character recognition programs), and LiDAR systems (which have integrated GPS technology and spatial data), onboard computers can control vehicle operation by combining machine vision, sensor data, and spatial data. It can be said that these technological advancements have laid the foundation for the development of "autonomous driving" by various automakers.
On the other hand, there are still some key technical issues to be resolved in order to achieve widespread adoption, including the standardization of communication protocols between vehicles, the issue of shared lanes for manned and unmanned vehicles, the establishment of a general software development platform, the fusion of information between multiple sensors, and the adaptability of visual algorithms to the environment.
