LiDAR Sensing Technology in Smart Rail

LiDAR plays an important role in smart rail transportation, so in what areas is LiDAR sensing technology used?

1.Track intrusion detection:

At present, there are two main types of railway safety protection facilities. One is to conduct manual inspections, and the other is to install video devices on lines prone to foreign body intrusion, analyze the collected videos in real time, and manually observe and process the data. However, the manual inspection cannot guarantee real-time performance; manual monitoring video may easily result in missing detection due to fatigue, and the automation degree is low. In railway operation, foreign body intrusion monitoring technology is an indispensable part.

LiDAR has strong anti-environmental interference ability, can accurately measure distance, and has a wide scanning range and field of view. The use of LiDAR sensing technology to realize the detection of foreign body intrusion in the railway can accurately detect whether there is foreign body intrusion in real time, and issue an alarm signal in time to ensure the safety of railway operation.

2. For rail transit obstacle detection:

The current rail transit obstacle detection technology is difficult to detect low-reflectivity, small-size targets with a color close to the surrounding environment or under low light conditions. By integrating LiDAR sensing technology and machine vision, obstacle detection technology solutions can achieve the purpose of fast, high-precision detection without restricting detection materials, and not being affected by changes in ambient light intensity, to better improve the safety factor in the operation of urban rail transit systems. 

3. For the urban rail transit survey:

The use of LiDAR sensing technology can quickly obtain massive 3D laser point clouds and digital image data of the surrounding environment of urban rail transit. It is an effective means to solve the problem of surveying and mapping the areas with complex landforms and features. Compared with traditional measurement methods, the survey efficiency of LiDAR technology is more than ten times that of traditional measurement methods, and LiDAR can greatly reduce the safety risk of field measurement.

4. Foreign body scanning of screen door:

At this stage, the design requirements of the screen door system have resulted in the gap between the screen door and the train body forming an unsafe closed space after the screen door is closed. In extreme cases, this enclosed space is enough to accommodate thin adults or children. If passengers are caught between the screen door and the train body, it will cause a potential safety accident.

The use of human intervention methods is easy to affect operational efficiency. There is an urgent need for more effective ways to deal with rail system operational efficiency.

LiDAR scanning foreign object detection system can effectively solve this problem. When the operating train enters the station, the LiDAR detection system automatically starts working, and at the same time determines the number of trains entering the station. After the system detects that the screen door is closed, it enters the detection mode. If the LiDAR sensing technology detects an object within the set area and time, if the judgment conditions are met, an alarm will be triggered, and the alarming screen door status will be transmitted to the terminal controller display screen and transferred to human intervention, which can effectively avoid false alarms and improve operational efficiency.

5. Deformation detection for subway tunnels

Aiming at the deformation problem of subway tunnels, LiDAR sensing technology can be used to scan and detect subway tunnels. The point cloud data measured by this method needs to be transformed into coordinates. During the preprocessing of point cloud data, denoise with an algorithm. The local deformation analysis is carried out on the detected section at the same position, and the section convergence analysis is carried out on the section at different positions in a certain section, to realize the deformation analysis of the subway tunnel section. Through the processing of this method, the deformation information of the subway tunnel can be the reference for the dynamic detection of subway tunnel deformation.

6. Safety protection between platforms and trains:

Since China’s urbanization construction, urban rail transit has developed rapidly, and the subway industry has paid more and more attention to the safety protection of the gap between the platform door and the train door, and they find ways to effectively ensure the safety of passengers staying in the gap. The stability and safety of LiDAR detection technology have been greatly improved for smart rail, and the accuracy has also been greatly improved. LiDAR sensing technology has broad application prospects in the safety protection of rail transit platform doors.

Neuvition Titan M1 series LiDAR

With a resolution of up to 700 lines and an angular resolution of 0.01°, Neuvition LiDAR Titan M1-R can effectively detect 600 meters, and meet the needs of faster measurement speed and higher measurement accuracy (up to ±2cm). Neuvition LiDAR uses a 1550nm laser which is a safe waveband for human eyes, can penetrate dense fog and dust, and adapt to harsh work environments. It meets the railway department’s requirements for vibration, radiation interference, different environmental temperatures, humidity, electromagnetic compatibility, etc.