A gap detection system and a laser radar-based gap detection method

Abstract

The application belongs to the technical field of rail transit, and proposes a gap detection system and a gap detection method based on a laser radar, which can effectively solve the problem of inaccurate detection of the existing detection method. The system comprises a control device and M detection devices; the M detection devices are used for detecting the gaps between all the platform screen doors and train doors, wherein each detection device is used for detecting multiple gaps, and each gap corresponds to N detection devices, N is greater than or equal to 2 and less than or equal to M; and the control device is used for judging whether there is an obstacle in the gap according to the detection results of the N detection devices of each gap.

Description

Technical Field

[0001] This application belongs to the field of urban rail transit technology, and in particular relates to a gap detection system and a gap detection method based on lidar. Background Technology

[0002] In urban rail transit, to ensure train operation safety, it is necessary to detect obstacles in the gaps between train platform screen doors and train doors. Currently, the common method is to install a detection device (such as a grating or lidar) between each set of platform screen doors and train doors to specifically detect whether there are obstacles between that set of platform screen doors and train doors.

[0003] However, during the detection process, interference from factors such as flying insects and dust in the gap between the train platform screen doors and the train doors can cause the detection equipment to misidentify these factors as obstacles and send a warning message to the train control system. Upon receiving the warning message, the control system needs to instruct staff to immediately open the platform screen doors for operational handling, and the train will not depart until the handling is completed. Because the detection equipment's detection results for obstacles in the gap are inaccurate, the warning message may actually be a false warning, resulting in longer operational handling time, reduced operational efficiency, and a poor user experience. Summary of the Invention

[0004] In view of this, embodiments of this application provide a gap detection system and a gap detection method based on lidar to solve the problem of inaccurate detection results in existing detection methods.

[0005] The first aspect of this application provides a gap detection system, including a control device and M detection devices; the M detection devices are used to detect the gaps between all platform screen doors and train doors, wherein each detection device is used to detect multiple gaps, and each gap corresponds to N detection devices, N≥2 and N≤M; the control device is used to determine whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices of the target gap.

[0006] In conjunction with the first aspect, in the first possible implementation of the first aspect, the gap feature information includes the detection accuracy α of the detection device. i The height parameter h of the detected obstacle i and the angular parameter θ of the obstacle i .

[0007] In conjunction with the first aspect, in the second possible implementation of the first aspect, the control device determines whether there is an obstacle in the target gap based on the gap feature information detected by N detection devices of the target gap, including: the control device generates N detection results of the target gap based on the gap feature information detected by the N detection devices of the target gap; wherein, the detection results are used to indicate whether there is an obstacle in the gap; if the N detection results are consistent, the control device outputs the detection results; if the N detection results are inconsistent, the control device controls some or all of the N detection devices to re-detect until the N detection results are consistent.

[0008] In conjunction with the first aspect, in the third possible implementation of the first aspect, the control device determines whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices of the target gap, including: if a preset number of the N detection devices are not working properly, the control device determines whether there is an obstacle in the target gap based on the gap feature information detected by the remaining working detection devices.

[0009] In conjunction with the first aspect, in the fourth possible implementation of the first aspect, the detection device is also used to determine whether an obstacle in the target gap affects the detection of other gaps based on the gap feature information detected by the N detection devices of the target gap.

[0010] In conjunction with the first aspect, in the fifth possible implementation of the first aspect, the control device determines whether an obstacle in the target gap affects the detection of other gaps by the following method: if an obstacle exists in the target gap, and the height parameter h of the obstacle... i Greater than the first preset threshold h x Or the angle parameter θ of the obstacle i Greater than the second preset threshold θ x If an obstacle in the target gap affects the detection of other gaps, then it is determined that the obstacle affects the detection of other gaps; if an obstacle exists in the target gap, and the height parameter h of the obstacle is... i Less than or equal to the first preset threshold h x Or the angle parameter θ of the obstacle i Less than or equal to the second preset threshold θ x If the obstacle in the target gap has no effect on the detection of other gaps, then it is determined that the obstacle has no effect on the detection of other gaps.

[0011] In conjunction with the first aspect, in the sixth possible implementation of the first aspect, the detection device includes a lidar, which includes a single-line lidar or a multi-line lidar.

[0012] In conjunction with the first aspect, in the seventh possible implementation of the first aspect, the system further includes an image acquisition device, a storage device, and a display device; the image acquisition device is used to acquire environmental data of the gap between the train platform screen door and the train door, and send the environmental data to the control device; the storage device is connected to the image acquisition device and multiple detection devices, and is used to store the environmental data acquired by the image acquisition device, as well as the gap feature information detected by the multiple detection devices; the display device is used to visualize the environmental data and gap feature information in the control device.

[0013] In conjunction with the first aspect, in the eighth possible implementation of the first aspect, the system further includes an alarm device; the alarm device is used to activate an alarm function when the control device determines that there is an obstacle in the target gap.

[0014] The second aspect of this application provides a gap detection method based on lidar, comprising: M detection devices equipped with lidar to detect all gaps between platform screen doors and train doors, wherein each detection device is used to detect multiple gaps, and each gap corresponds to N detection devices, N≥2 and N≤M; and a control device to determine whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices of the target gap.

[0015] The beneficial effects of this application embodiment compared with the prior art are as follows: In the gap detection system and method provided in this embodiment, the system includes multiple detection devices and a control device. Each detection device can detect multiple gaps, ensuring that the detection devices can cover all gaps in the train. Furthermore, each gap is detected by multiple detection devices set at different locations. Then, the control device analyzes the multiple detection results for each gap to determine whether there is an obstacle in that gap. Therefore, the presence or absence of an obstacle in each gap is determined by the control device based on the detection results of the multiple detection devices detecting that gap. Thus, this detection method provides more accurate and efficient obstacle determination results, thereby more effectively reducing the probability of false warnings. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram illustrating a scenario where a train platform screen door and a train door are positioned, as provided in an embodiment of this application.

[0018] Figure 2This is a schematic architecture diagram of the gap detection system provided in the embodiments of this application;

[0019] Figure 3 This is a schematic diagram of the installation of multiple detection devices provided in the embodiments of this application;

[0020] Figure 4 This is a schematic diagram of a scenario where multiple detection devices provided in this application cover the gaps between trains;

[0021] Figure 5 This is a schematic diagram of a scenario where the lidar covers a corresponding number of detection gaps, as provided in an embodiment of this application.

[0022] Figure 6 This is a schematic diagram of obstacle feature information provided in an embodiment of this application;

[0023] Figure 7 This is a schematic diagram illustrating the impact of obstacles in the near-end gap of the distance detection device on the detection of the far-end gap, as provided in the embodiments of this application.

[0024] Figure 8 This is a schematic diagram of the detection range of the multi-line lidar provided in the embodiments of this application;

[0025] Figure 9 This is a top view of the subway car and platform screen doors provided in an embodiment of this application;

[0026] Figure 10 This is a flowchart of the gap detection method provided in the embodiments of this application. Detailed Implementation

[0027] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0028] To illustrate the technical solution described in this application, specific embodiments are provided below.

[0029] In urban rail transit, to ensure the safety of trains and passengers, train operators install protective barriers on train platforms. These barriers separate the platform from the train operating area, preventing passengers from accidentally falling onto the tracks and protecting their safety. The protective barriers are equipped with platform screen doors, either the same number as or greater than the number of train doors, as well as fixed doors spaced at intervals between the platform screen doors. When the number of train doors and platform screen doors are the same, the location of each platform screen door corresponds to the location of the train doors when the train arrives at the station. See also... Figure 1 As shown, Figure 1 When a train arrives at a station, both the platform screen doors and the train doors open simultaneously to allow passengers to board and alight. If the number of platform screen doors exceeds the number of train doors, both the train doors and their corresponding platform screen doors will open simultaneously upon arrival. Platform screen doors exceeding the number of train doors will generally remain closed.

[0030] It should be understood that to ensure the normal operation of the train, there are gaps between the train and the protective wall, and similarly, there are gaps between the platform screen doors and the train doors. Normally, these gaps can accommodate small individuals or children. If, after the train has departed, there are obstacles, children, or small individuals within these gaps, it could lead to a serious accident. Therefore, to ensure that there are no obstacles in any gap of the train when it is preparing to depart, it is necessary to perform obstacle detection on each gap.

[0031] To ensure train operation safety, platforms are typically equipped with gap detection systems. These systems use a detection device (such as a grating radar or lidar) to detect obstacles in the gap between each train door and the platform screen door. After completing the detection, the device reports the results to the control center, which then prompts staff to take appropriate action.

[0032] However, when using the aforementioned gap detection system to detect train gaps, interference factors such as flying insects and dust can affect the accuracy of the detection results. For example, during detection, flying insects or dust may sometimes adhere to the surface of the detection equipment's lens, affecting its normal operation; or during laser detection, due to the uncertainty of the flying direction of flying insects in the environment, the laser may reflect back when it encounters an insect, thus indicating the presence of an obstacle in the gap and generating a false alarm. The laser detection equipment then reports this false alarm to the control terminal, which prompts staff to handle it. Regardless of whether the detection result received by the control terminal is a normal alarm or a false alarm, manual intervention is required. When the probability of a false alarm per door is constant (assuming it is 1‰), for a train with 32 doors, the probability of a false alarm increases exponentially (31.5‰). When an alarm occurs in each gap, staff must immediately open the platform screen doors for operational handling. The train can only depart after the staff has finished handling the situation, thus prolonging the operational handling time, reducing operational efficiency, and resulting in a poor operational experience.

[0033] Furthermore, if a single gap detection device malfunctions during the detection process, staff must bypass the detection process to repair it until the detection device for that gap is fixed. Therefore, for extended periods of train operation, the platform screen doors corresponding to the detection device must be bypassed, preventing them from opening or closing. Alternatively, staff must visually inspect the doors before each train enters the station and before the doors open or close. This method of detecting single gaps not only impacts train operation efficiency but also increases the workload of staff.

[0034] To address the aforementioned problems, this application provides a gap detection system. This system utilizes multiple detection devices to detect the gaps between trains from different angles. Then, it comprehensively arbitrates the gap characteristic information of each gap to obtain the gap detection result for all gaps in the train. Based on this gap detection result, the operating status of the target train is controlled. This gap detection method can eliminate interference from flying insects and reduce the false alarm rate.

[0035] Figure 2 This is a schematic architecture diagram of the gap detection system provided in this embodiment. See also... Figure 2 As shown, the gap detection system includes a control device and M detection devices. The number of detection devices M can be the same as or different from the number of train doors. In one example, if the number of train doors is 32, then the value of the number of detection devices M is also 32.

[0036] In this embodiment, the control device communicates with each detection device. The communication methods include, but are not limited to, wired communication methods such as Controller Area Network (CAN) communication, 485 serial communication, network communication, and fiber optic communication, as well as wireless communication methods such as cellular communication, Wi-Fi, Bluetooth, and Zigbee.

[0037] The detection equipment, also known as detection terminal equipment, is deployed at the top of the gaps between trains. For example, each detection device can be installed at the top of a fixed door centerline. Optionally, when the installation distance between the various platform screen doors or train doors is determined, the installation height and position of the detection equipment can be moved horizontally or vertically according to actual needs. That is, the installation position of each detection device does not necessarily have to be fixed at the top of a fixed door centerline; it can be adjusted according to the performance of the detection equipment.

[0038] In some embodiments, because each train carriage has a relatively long distance and the length of each carriage cannot be uniformly set, it is impossible to achieve a uniform distribution of each detection device during installation. Therefore, the overall detection performance of the system can be ensured by grouping carriages together or by simply adding detection devices. For example, if the length of a certain carriage is longer than other carriages, detection devices can be added to that carriage; if the length of a certain carriage is shorter than other carriages, the number of detection devices can be appropriately reduced, or a detection method using different types of detection devices working together can be adopted. The specific choice can be made according to actual needs, and this embodiment does not impose specific limitations.

[0039] Figure 3 This is a schematic diagram illustrating the installation of multiple detection devices provided in this embodiment. For example, multiple detection devices are deployed at a certain height above the centerline of each fixed door. The installation height of the multiple detection devices can be set according to the detection performance of different devices. The higher the detection accuracy of a device, the higher its installation height can be; conversely, the lower the detection accuracy, the lower the installation height can be to ensure the accuracy of the detection results.

[0040] In this embodiment, please refer to Figure 4 As shown, the combined detection range of M detection devices can cover all gaps between platform screen doors and train doors. Each detection device can detect multiple gaps between platform screen doors and train doors. Furthermore, for each gap between a platform screen door and a train door, N detection devices detect it, where N ≥ 2 and N ≤ M. In one example, N = 4, meaning that for each gap between a platform screen door and a train door, 4 detection devices detect it.

[0041] In some embodiments, the detection device described above may be a lidar or an image acquisition device for collecting environmental data in various gaps.

[0042] In other embodiments, the detection device described above may also be a combined detection device of lidar and image acquisition device, which detects gaps through the synergistic effect of the two.

[0043] In other embodiments, the multiple detection devices may also be an integrated lidar with built-in video functionality. During the detection process, the integrated lidar can simultaneously acquire video images of the target detection point and upload the acquired video images to the control device.

[0044] In this embodiment, the number of gaps that each detection device can detect is determined by the detection performance of each of the multiple detection devices. For example, when the detection device is a lidar, taking a detection radius of 10m for each lidar, the diameter of each train car is approximately 20m, and the distance between the platform screen doors is approximately 5m. Therefore, the detection area of ​​each lidar can cover the gaps between four train doors and platform screen doors. Thus, the lidar can be positioned at the top of the centerline between the four covered platform screen doors. The closer the gap is to the lidar, the more accurate the detection result will be. (See attached diagram.) Figure 5 As shown, Figure 5 A0, A1, A2, A3, and A4 in the diagram indicate the locations of the gaps between the train doors and the platform screen doors. Figure 5 The lidar devices D1, D2, D3, and D4 shown in the diagram all have a detection radius of 10m. Lidar D2 can cover gaps A0, A1, A2, and A3, while lidar D3 can cover gaps A1, A2, A3, and A4. Taking lidar D3 as an example, after laser detection, the gap feature information of gaps A1, A2, A3, and A4 within the current light curtain cross-section can be obtained.

[0045] The control equipment, also known as the control terminal equipment, is deployed in the main control room. It is associated with the opening and closing system of the platform screen doors and train doors, and is connected to multiple detection devices. It is used to determine whether there are obstacles in the corresponding gap based on the detection results sent by N detection devices in each gap.

[0046] In some embodiments, the control device may be a computer or a laser control device, wherein the laser control device has a built-in microcontroller (MCU) or programmable logic controller (PLC). The number of control devices can be one or multiple. When there is only one control device, it needs to store and back up the data generated during the execution of control operations. When there are multiple control devices, if one fails to function properly, another control device can perform the control operation to ensure the stable operation of the system.

[0047] In some embodiments, the gap detection system can be installed inside the station or on the train. For example, when the gap detection system is installed inside the station, the control equipment can be located in the main control room, and the detection equipment can be positioned at the top of the gap between the platform screen doors inside the station; when the gap detection system is installed on the train, the control equipment can be located in the train's control room, and the detection equipment can be positioned at the top of the gap between the train doors. In actual deployment, the configuration can be adjusted according to the specific circumstances, and this embodiment does not impose specific limitations.

[0048] In this embodiment, when multiple detection devices perform obstacle detection on the same gap, each detection device collects gap feature information and then sends this information to the control device. For example, the gap feature information includes the detection accuracy α of the lidar relative to each gap. i The height parameter h of the obstacle i θ, the angle parameter of the obstacle i See also Figure 5 As shown in the diagram, taking lidar D3 as an example, after the train gaps are detected by lidar D3, the gap feature information of gaps A1, A2, A3, and A4 within the current light curtain section can be obtained. The gap feature information of lidar D3 for gap A1 is D3_A1(α1, h1, θ1), for gap A2 it is D3_A2(α2, h2, θ2), for gap A3 it is D3_A3(α3, h3, θ3), and for gap A4 it is D3_A4(α4, h4, θ4). And so on, the gap feature information of each lidar for all the gaps it can detect can be obtained.

[0049] The following section explains the calculation method and meaning of the gap feature information.

[0050] In this embodiment, the detection accuracy α of the lidar relative to each gap i The detection accuracy k of the lidar i And the degree of obstruction of this gap by obstacles in adjacent gaps. Among them, the detection accuracy k i The value is inversely related to the distance between the lidar and the detection point. For example, let the lidar's detection accuracy k... i The values ​​are explained as fixed values. Please refer to the appendix. Figure 5 If the detection accuracy k1 of lidar D3 for gap A1, which is farther away from it, is 1, then the detection accuracy k2 for gap A2, which is closer to it, is 2. If the detection accuracy k3 for gap A2, which is closer to it, is 2, then the detection accuracy k4 for gap A1, which is farther away from it, is 1.

[0051] In some embodiments, for lidar D3, if an obstacle in gap A2 obstructs the detection of gap A1, the value of α1 is -1*k1; otherwise, it is k1. Similarly, if an obstacle in gap A3 obstructs the detection of gap A4, the value of α4 is -1*k4; otherwise, it is k4. The detection result of gap A2 is not affected by other obstructions, so the value of α2 is k2. Likewise, the detection result of gap A3 is not affected by other obstructions, so the value of α3 is k3.

[0052] In this embodiment, the height parameter h of the obstacle i This refers to the projection of two points on the maximum cross-section of the obstacle from the detection point where the detection equipment is located, in the direction perpendicular to the ground. See also Figure 6 As shown, the line connecting the detection point C of lidar D3 and points A and B of the maximum cross-section of obstacle 1 is used as the schematic straight line of the obstacle, as follows. Figure 6 Lines AC and BC are shown in the diagram. Obstacles 1, 2, and 3 all have a projection height of h on the vertical ground, as shown in the diagram. i .

[0053] In this embodiment, the angle parameter θ of the obstacle i This is the angle between the detection point where the detection device is located and two points on the maximum cross-section of the obstacle, in the direction perpendicular to the ground. See also Figure 6 As shown, the angle between the line AC connecting the highest point A of obstacle 1 and the detection point C of lidar D3 in the vertical direction is... Figure 6 θ2 in.

[0054] In some embodiments, the gap feature information detected by the detection device is the height parameter h of the obstacle when no obstacle is detected. i Angular parameter θ relative to the obstacle i All are 0.

[0055] In the gap detection process provided in this embodiment, each detection device can detect multiple gaps between platform screen doors and train doors. Therefore, except for gaps located adjacent to each other on both sides of the detection point of the detection device, when the detection device detects gaps at a more distant end, it will be affected by the height parameter of obstacles in gaps at a closer end. To determine whether the presence of an obstacle in a certain gap will affect the detection of its adjacent gaps during the detection process, the following method is used for determination. For example, please refer to the appendix. Figure 7 As shown, if the height h of the obstacle within gap A2 is... i Greater than h x , and θ i Greater than θ x If an obstacle within gap A2 affects the detection result of gap A1, then the maximum value of the angle parameter of the obstacle affecting the detection result of gap A1 can be calculated using the following formula:

[0056]

[0057]

[0058] Where L0 is the width of the fixed door, L1 is the width of the shielded door, H is the installation height of the LiDAR D3 (usually 2.56-3 meters from the ground), and after the LiDAR D3 is installed and fixed, the values ​​of L0 and L1 are customized, θ i The value range is from 0 to 90 degrees. When θ2 (the detection angle of lidar D3 on gap A2) is greater than θ x Or h2 (the obstacle detection height of lidar D3 in gap A2) is greater than h x When θ2 is less than or equal to θ, it indicates that the obstacle in gap A2 has affected the detection of gap A1 by lidar D3. Therefore, the detection result of lidar D3 on gap A1 is inaccurate at this time, and the detection accuracy α1 of lidar D3 on gap A1 is 0. Conversely, when θ2 is less than or equal to θ... x , or h2 is less than or equal to h x When the obstacle in gap A2 does not affect the detection of gap A1 by lidar D3, it is considered that the detection result of lidar D3 on gap A1 is accurate, and the detection accuracy α1 of lidar D3 on gap A1 is k1. Since the detection of gap A2 by lidar D3 is not affected by obstacles in other gaps, the detection accuracy α2 of lidar D3 on gap A2 is k2.

[0059] From the above, we can see that Figure 5 The detection accuracy of gaps A3 and A4 is determined as follows: When θ3 (the detection angle of lidar D3 on gap A3) is greater than θ... x Or h3 (the obstacle detection height of lidar D3 over gap A3) is greater than h x When θ3 is less than or equal to θ4, it indicates that the obstacle in gap A3 has affected the detection of gap A4 by lidar D3. Therefore, the detection result of lidar D3 on gap A4 is inaccurate at this time, and the detection accuracy α1 of lidar D3 on gap A4 is 0. Conversely, when θ3 is less than or equal to θ4... x , or h3 is less than or equal to h x When the obstacle in gap A3 does not affect the detection of gap A4 by lidar D3, it is considered that the detection result of lidar D3 for gap A4 is accurate, and the detection accuracy α4 of lidar D3 for gap A4 is k4. Since the detection of gap A3 by lidar D3 is not affected by obstacles in other gaps, the detection accuracy α3 of lidar D3 for gap A3 is k3.

[0060] As can be seen, in this embodiment, different detection devices will produce different detection results for the same gap, as they are affected by obstacles in adjacent gaps. Therefore, after multiple detection devices send the detected gap feature information to the control device, the control device performs comprehensive processing based on the received gap feature information. For example, the gap feature information of gap A2 consists of D1_A2(α4, h4, θ4) of lidar D1, D2_A2(α3, h3, θ3) of lidar D2, D3_A2(α2, h2, θ2) of lidar 3, and D4_A2(α1, h1, θ1) of lidar D4. The final obstacle determination is the comprehensive processing result of the four lidars.

[0061] In this embodiment, the lidar can be a single-line lidar or a multi-line lidar. A single-line lidar consists of a laser emitter and a 360-degree rotating scanner. Its working principle is to emit a detection signal (laser beam) within a single light curtain section towards the target, then compare the received signal reflected back from the target (target echo) with the emitted signal. After appropriate processing, relevant information about the target can be obtained, such as target distance, azimuth, altitude, speed, attitude, and even shape parameters. A multi-line lidar, on the other hand, emits detection signals (laser beams) within multiple light curtain sections towards the target. For example, using... Figure 7 Taking the lidar D3 shown as an example, when the gap between the platform screen door and the train door is d, the length of the gap A1 that lidar D3 needs to detect is L = 2L1 + 3L0 / 2. The installation height of lidar D3 is H, then the milliradian (miradian) of the lidar D3's beam is φ. The milliradian (miradian) φ can be calculated as follows: When H = 3m, L = 10m, and d = 20cm, by using the Pythagorean theorem and the triangle angle formula, φ is 19.16 milliradians. When lidar D3 is a single-line lidar, its beam size must be less than 19.16 milliradians. When lidar D3 is a four-line lidar, its beam size is 1 / 4φ, such as... Figure 8 and Figure 9 As shown, the spot size of the lidar D3 must be less than 4.79 milliradians.

[0062] It should be understood that when the required number of lines for a multi-line lidar is 32, the gap width d between the train platform screen doors and fixed doors is typically less than 20cm due to design specifications. Therefore, when a 32-line multi-line lidar with a φ of less than 0.59 milliradians is selected, it can almost cover the entire gap.

[0063] In some embodiments, the control device processes the gap feature information sent by multiple detection devices and combines it with the operating status of the detection devices to obtain the gap detection result for each gap of the train. Then, based on the gap detection result, the control device controls the opening and closing of the platform screen door and the train door, thereby controlling the operating status of the target train.

[0064] In this embodiment, the control device processes the gap feature information received from multiple detection devices using the following gap detection method, see [link to relevant documentation]. Figure 10 As shown, the specific steps include S1-S3:

[0065] S1. The control equipment acquires the gap characteristic information of the train target gap collected by different detection devices.

[0066] In this embodiment, the target gap is the gap between any train door and the platform screen door. The control device acquires the gap feature information of each target gap collected from different angles by multiple detection devices. For example, please refer to the appendix. Figure 3 Each detection device (LiDAR) can detect four gaps. The detection gaps covered by LiDAR D1 are gaps A0, A1, A2, and gap A0 to the left of gap A1. -1 (Not shown in the diagram), after the gap between the trains is detected by lidar D1, lidar D1 determines the gap A. -1 The detection result is D1_A -1 (α -1 h -1 θ -1The detection results for gap A0 are D1_A0(α0, h0, θ0), for gap A1 are D1_A1(α1, h1, θ1), and for gap A2 are D1_A2(α2, h2, θ2). The detection gaps covered by lidar D2 are gaps A0, A1, A2, and A3. After detection by lidar D2, the detection results for gap A0 are D2_A0(α0, h0, θ0), for gap A1 are D2_A1(α1, h1, θ1), for gap A2 are D2_A2(α2, h2, θ2), and for gap A3 are D2_A3(α3, h3, θ3). The detection gaps covered by lidar D3 are gaps A1, A2, A3, and A4. After the train gaps are detected by lidar D3, the detection results of lidar D3 for gap A1 are D3_A1(α1, h1, θ1), for gap A2 are D3_A2(α2, h2, θ2), for gap A3 are D3_A3(α3, h3, θ3), and for gap A4 are D3_A4(α4, h4, θ4). The detection gaps covered by lidar D4 are gaps A2, A3, A4, and the right gap A5 (not shown in the figure). After the train gaps are detected by lidar D4, the detection results of lidar D4 for gap A2 are D4_A2(α2, h2, θ2), for gap A3 are D4_A3(α3, h3, θ3), for gap A4 are D4_A4(α4, h4, θ4), and for gap A5 are D4_A5(α5, h5, θ5).

[0067] In this embodiment, the detection accuracy α in the above-mentioned gap feature information i The height parameter h of the obstacle i θ, the angle parameter of the obstacle i The calculation method is described in the above gap detection system regarding the detection equipment, and will not be repeated in this embodiment.

[0068] S2. The control device determines the gap detection result of the target gap based on the gap characteristic information of the target gap.

[0069] In this embodiment, the detection device is based on the detection accuracy α of the target gap detected by the target detection device. i The height parameter h i and the angle parameter θ i It outputs the detection results of the target detection device regarding whether there are obstacles in the gap between the target.

[0070] For example, the detection accuracy α1 of the target detection device in detecting the target gap is greater than or equal to the detection accuracy α2 of the adjacent gap, and the height parameter h i and angle parameter θ i When all values ​​are not equal to 0, the control device outputs a detection result from the target detection device indicating the presence of an obstacle in the target gap. For example, if the detection accuracy α1 of the target detection device in detecting the target gap is greater than or equal to the detection accuracy α2 of the adjacent gap, and the height parameter h... i and angle parameter θ i When all values ​​are equal to 0, the control device outputs a detection result indicating that there are no obstacles in the gap between the target and the target.

[0071] In some embodiments, when the control device determines the gap detection result of the target gap based on the gap feature information of the target gap, it can make a determination by determining whether the detection results of the N detection devices that detect the target gap are consistent and whether all N detection devices can work normally.

[0072] In the first scenario, all N detection devices can operate normally. As can be seen from the above detection method, due to the different settings of the detection devices relative to the gap, the detection results of each detection device for the target gap will vary.

[0073] In some embodiments, when the gap detection results obtained by the control device from processing the gap feature information of the target gap of the train by N detection devices are all consistent, the consistent detection result is output. This consistent detection result includes the presence or absence of an obstacle. If the determination result is that an obstacle exists in the target gap, the gap detection result for that target gap is output; if the determination result is that no obstacle exists in the target gap, the gap detection result for that target gap is output.

[0074] When the control device determines that there are no obstacles in the target gap, it indicates that the gap feature information detected by N detection devices, such as lidar, is D. i _A i (α i h i θ i ), where i ranges from 1 to N, α i The detection accuracy of each lidar is given by h. Since all N detection devices are functioning normally and there are no obstacles obstructing their view, this detection accuracy represents the inherent detection accuracy of the detection devices themselves. i θ i All are 0.

[0075] When the control device determines that a gap detection result indicates the presence of an obstacle in the target gap, the installation positions of the N detection devices relative to each gap may not be exactly the same. However, the control device can process the gap feature information fed back by the N detection devices to determine the height and size characteristics of the obstacle in the target gap, and then proceed with further processing based on these height and size characteristics. For example, this processing can be automated or manual, such as opening the shielding door, restarting the detection devices, or issuing an alarm. Furthermore, when the control device determines that a gap detection result indicates the presence of an obstacle in the target gap, and the gap feature information detected by the N detection devices indicates that the presence of the obstacle will affect the gap detection results of other gaps, then further processing based on the presence of an obstacle will proceed. The specific determination of whether the presence of an obstacle will affect the gap detection results of other gaps can be based on the description of the detection devices in the gap detection system described above, and will not be elaborated upon in this embodiment.

[0076] In some embodiments, when the detection result obtained by the control device based on the gap feature information of N detection devices on the train target gap is inconsistent with the detection result obtained based on the gap feature information of one of the detection devices, the control device controls the detection device with inconsistent detection results to re-detect. After the re-detection is completed, if the detection result is consistent, the consistent result is used as the gap detection result, and further processing is performed based on the gap detection result. If the detection result is still inconsistent, a manual processing procedure is performed. In this embodiment, multiple detection and confirmation operations can improve the accuracy and prevent the occurrence of flying insects, dust layers, etc.

[0077] In some embodiments, when the detection results obtained by the control device based on the gap feature information of N detection devices are inconsistent with those of other detection devices, the control device controls the detection devices with inconsistent detection results to re-detect. For example, assuming each detection device can detect four gaps, and one gap can be detected by four detection devices, if the detection results obtained by the control device based on the gap feature information of two detection devices are inconsistent with the detection results obtained by other detection devices, the control device controls the two detection devices with inconsistent detection results to re-detect. After re-detection, if the detection results are consistent, the consistent result is used as the gap detection result, and further processing is performed based on this gap detection result. If the detection results are still inconsistent, the detection devices with inconsistent output results are controlled to perform three or more detections. If the results are still inconsistent, all detection devices are controlled to re-collect gap feature information and recalculate the gap detection results. If the detection results of all detection devices are consistent at this time, the consistent result is used as the gap detection result, and further processing is performed based on this gap detection result. If the results are still inconsistent, a manual processing procedure is performed.

[0078] In the second scenario, when N detection devices capable of measuring the same gap cannot all function properly, if the number of malfunctioning devices is less than or equal to a second preset number, the control device performs calculations and arbitration based on the detection results of the remaining functional detection devices. For example, assuming each detection device can detect four gaps, and one gap can be detected by four detection devices, if not all four detection devices function properly, and the number of malfunctioning devices is less than or equal to two, the control device can perform calculations and arbitration based on the detection results of the remaining functional detection devices. In this embodiment, the control device can increase the number of detections and the confirmation process of the remaining functional detection devices by using the second preset number of malfunctioning detection devices, thereby improving accuracy. Simultaneously, the control device can report faults based on the gap detection results, prompting personnel to prepare for maintenance work.

[0079] In some embodiments, when one or two non-adjacent detection devices among all detection devices capable of measuring the same gap are malfunctioning, the control device can determine the final detection result based on the detection results of the remaining detection devices. Similarly, when two adjacent detection devices among all detection devices capable of measuring the same gap are malfunctioning, the control device can determine the final detection result based on the detection results of the remaining detection devices. In this case, the accuracy of the gap detection result can be improved by increasing the number of detections by the remaining detection devices and streamlining the confirmation process.

[0080] In some embodiments, when the control device analyzes the gap feature information collected by the detection device, the obtained arbitration obstacle height H is... 2y The value can be the gap feature information h. i The weighted average after removing the highest and lowest values. Furthermore, when Δh = |h i -H 2y If the value is greater than the threshold m, the data is deemed to have no reference value and is discarded without being used for calculation or judgment.

[0081] In other embodiments, the judgment result obtained by the control device from the acquired gap feature information can be a general truth table judgment, or it can be correlated with the acquired obstacle height for judgment.

[0082] S3. The control equipment controls the running status of the target train based on the gap detection results of each target gap.

[0083] In this embodiment, the gap detection result of the control device for a certain target gap is calculated and arbitrated by the detection results of each detection device to determine whether the obstacle exists, and further control the opening and closing of the platform screen door and the train door, that is, disconnecting or closing the safety circuit.

[0084] For example, when the clearance detection result obtained by the control equipment is that there is no obstruction, the platform screen door and train door are closed, and the target train is controlled to run. When the clearance detection result obtained by the control equipment is that there is an obstruction, the safety circuit is disconnected, the target train is controlled to stop, a fault is reported, and staff are prompted to prepare for maintenance work.

[0085] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0086] The gap detection system provided in this application, in some embodiments, further includes an end gate display device, a video storage device, and a video display device.

[0087] The end gate display device, located in the main control room and connected to the control equipment, is used to control the display of gap feature information received from multiple detection devices. The control equipment and the end gate display device communicate via, but are not limited to, network cables, CAN cables, and High Definition Multimedia Interface (HDMI) cables.

[0088] The video storage device is connected to the control device. When the detection device in the gap detection system is an integrated LiDAR with built-in video function, the control device stores the received video images in the video storage device for easy retrieval when visualization is required.

[0089] The video display device is connected to the control device. When the detection device in the gap detection system is an integrated LiDAR with built-in video function, the control device will visualize the received video image on the video display device, which increases another way to determine whether there is an obstacle and reduces the probability of generating false warnings.

[0090] It should be noted that the video display device and the end gate display device can be the same device or separate devices configured with different functions and performing different operations.

[0091] In some embodiments, the gap detection system further includes an alarm device connected to the control device. When the control device determines that the gap detection result indicates the presence of an obstacle, the alarm device initiates an alarm to prompt personnel to take appropriate action. Optionally, the alarm device includes multiple alarm units, each corresponding to a specific gap on the train. When the control device activates the alarm, it can precisely control the alarm unit corresponding to the gap with the obstacle to generate an alarm. For example, the alarm unit can be a red-green indicator light; a green indicator light illuminates when there is no obstacle in the gap corresponding to the alarm unit, and a red indicator light illuminates when there is an obstacle in the gap.

[0092] In some embodiments, the alarm device can be integrated into the end gate display device. When there is an obstacle in the corresponding train gap, the alarm information is displayed visually on the end gate display device to prompt the operator to take further action on the alarm information.

[0093] The gap detection system and control method provided in this embodiment utilize multiple detection devices to detect the same gap from different angles, comprehensively arbitrarily determining the presence of obstacles. This effectively eliminates interference from flying insects and reduces false alarm rates. Furthermore, even when two adjacent detection devices malfunction simultaneously, the system can still produce accurate detection results, improving operational efficiency.

[0094] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0095] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, phrases such as "in one embodiment," "in some embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0096] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A gap detection system, characterized in that, Includes control equipment and M detection devices; The M detection devices are used to detect all gaps between the platform screen doors and the train doors. Each detection device is used to detect multiple gaps, and each gap corresponds to N detection devices set at different positions, where N≥2 and N≤M. The detection devices include lidar and / or image acquisition devices for collecting environmental data of each gap. The control device is used to determine whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices of the target gap; the gap feature information includes the detection accuracy α of the detection devices. i The height parameter h of the detected obstacle i and the angular parameter θ of the obstacle i The detection accuracy αi of the lidar relative to each gap is related to the detection precision ki of the lidar and the degree of obstruction of the gap by obstacles in adjacent gaps; wherein, the detection precision ki value is inversely related to the distance between the lidar and the detection point; the height parameter h of the obstacle... i The projection of the detection point where the detection device is located and two points on the maximum cross-section of the obstacle onto the direction perpendicular to the ground; The detection device is also used to determine whether an obstacle in the target gap affects the detection of other gaps based on the gap feature information detected by the N detection devices of the target gap; The control device determines whether an obstacle in the target gap affects the detection of other gaps by using the following method: If there is an obstacle in the target gap, and the height parameter h of the obstacle is... i Greater than the first preset threshold h x or the angle parameter θ of the obstacle i Greater than the second preset threshold θ x If an obstacle in the target gap affects the detection of other gaps, then it is determined that the obstacle affects the detection of other gaps; if an obstacle exists in the target gap, and the height parameter h of the obstacle is... i Less than or equal to the first preset threshold h x or the angle parameter θ of the obstacle i Less than or equal to the second preset threshold θ x If an obstacle in the target gap has no effect on the detection of other gaps, then it is determined that the obstacle has no effect on the detection of other gaps. If an obstacle in the target gap causes a certain detection device to affect the detection of other gaps, then the detection accuracy of that detection device for other gaps is 0.

2. The system according to claim 1, characterized in that, The control device determines whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices, including: The control device generates N detection results for the target gap based on the gap feature information detected by the N detection devices; wherein, the detection results are used to indicate whether there is an obstacle in the gap; If N detection results are consistent, the control device outputs the detection result; If the N detection results are inconsistent, the control device controls some or all of the N detection devices to re-detect until the N detection results are consistent.

3. The system according to claim 1 or 2, characterized in that, The control device determines whether there is an obstacle in the target gap based on the gap feature information detected by the N detection devices, including: If a predetermined number of the N detection devices are not functioning properly, the control device determines whether there is an obstacle in the target gap based on the gap feature information detected by the remaining functioning detection devices.

4. The system according to claim 1, characterized in that, The lidar includes single-line lidar or multi-line lidar.

5. The system according to claim 1, characterized in that, The system also includes image acquisition devices, storage devices, and display devices; The image acquisition device is used to acquire environmental data of the gap between the train platform screen door and the train door, and send the environmental data to the control device; The storage device is connected to the image acquisition device and the plurality of detection devices, and is used to store environmental data acquired by the image acquisition device and gap feature information detected by the plurality of detection devices; The display device is used to visualize the environmental data and the gap feature information in the control device.

6. The system according to claim 1, characterized in that, The system also includes alarm devices; The alarm device is used to activate the alarm function when the control device determines that there is an obstacle in the target gap.

7. A gap detection method based on lidar, characterized in that, The method includes: M detection devices equipped with lidar are used to detect all gaps between the platform screen doors and the train doors. Each detection device is used to detect multiple gaps, and each gap corresponds to N detection devices set at different positions, where N≥2 and N≤M. The detection devices include lidar and / or image acquisition devices for collecting environmental data of each gap. The control device determines whether an obstacle exists in the target gap based on the gap feature information detected by N detection devices; the gap feature information includes the detection accuracy α of the detection devices. i The height parameter h of the detected obstacle i and the angular parameter θ of the obstacle i The detection accuracy αi of the lidar relative to each gap is related to the detection precision ki of the lidar and the degree of obstruction of the gap by obstacles in adjacent gaps; wherein, the detection precision ki value is inversely related to the distance between the lidar and the detection point; the height parameter h of the obstacle... i The projection of the detection point where the detection device is located and two points on the maximum cross-section of the obstacle onto the direction perpendicular to the ground; The detection device is also used to determine whether an obstacle in the target gap affects the detection of other gaps based on the gap feature information detected by the N detection devices of the target gap; The control device determines whether an obstacle in the target gap affects the detection of other gaps by using the following method: If there is an obstacle in the target gap, and the height parameter h of the obstacle is... i Greater than the first preset threshold h x or the angle parameter θ of the obstacle i Greater than the second preset threshold θ x If an obstacle in the target gap affects the detection of other gaps, then it is determined that the obstacle affects the detection of other gaps; if an obstacle exists in the target gap, and the height parameter h of the obstacle is... i Less than or equal to the first preset threshold h x or the angle parameter θ of the obstacle i Less than or equal to the second preset threshold θ x If an obstacle in the target gap has no effect on the detection of other gaps, then it is determined that the obstacle has no effect on the detection of other gaps. If an obstacle in the target gap causes a certain detection device to affect the detection of other gaps, then the detection accuracy of that detection device for other gaps is 0.

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