A vehicle dynamic envelope detection apparatus and method

Abstract

The application discloses a kind of vehicle dynamic envelope detection device and method, including vehicle body and the laser scanner of setting in the front side of vehicle body, and the front acquisition support and rear acquisition support of setting in the bottom of vehicle body, laser scanner is used to collect and obtain rail section profile point cloud and limit contour point cloud;Two first laser displacement sensors are provided on the front acquisition support, two second laser displacement sensors are provided on the front acquisition support, and the three-dimensional coordinates of gauge measuring point are measured by first laser displacement sensor and second laser displacement sensor.It also includes the detection method steps of S1-S6.The detection device of the application cooperates method, by simplifying detection structure and optimizing detection method, reduce the deviation of calculation result and actual value, only by the attitude change of vehicle body directly calculates the dynamic offset of vehicle body, so that it can more truly reflect the dynamic offset of vehicle, while dynamically testing building limit, whether dynamic offset exists overrun risk can be displayed in real time.

Description

Technical Field

[0001] This invention relates to the field of rail transit measurement, and more particularly to a vehicle dynamic envelope detection device and method. Background Technology

[0002] Trains need to operate at high speeds in a specific space, the dimensions of which are called clearances. During operation, the boundary conditions for vehicle offset must be within these clearances. Dynamic offset refers to the response of a moving vehicle to external stimuli, including lateral movement clearance of wheelsets, bogie offset, car body offset relative to the frame, lateral displacement caused by bogie roll, and the maximum vehicle offset caused by car body roll. Regular and accurate inspection of the train's envelope, early detection of defects, and targeted remediation of serious defects not only saves maintenance costs but is also a crucial means of ensuring railway transportation safety. However, traditional dynamic offset detection relies on manual operation, which is labor-intensive, time-consuming, and difficult to achieve comprehensive and accurate detection. Efficient, automated, and intelligent new technologies for envelope clearance condition detection are an important means and an inevitable trend in solving this problem. Current envelope limit state detection technologies mainly rely on calculations to determine the dynamic offset of a vehicle. This method involves multiple parameters, including primary and secondary suspension parameters, the mass of various components, and wheel-rail wear. The calculations are complex and involve numerous parameters, leading to significant discrepancies between the calculated results and actual values, thus failing to accurately reflect the vehicle's dynamic offset. Therefore, it is necessary to propose a vehicle dynamic envelope detection device and method. Summary of the Invention

[0003] To address the aforementioned shortcomings of existing technologies, this invention provides a vehicle dynamic envelope detection device and method. By simplifying the detection structure and optimizing the detection method, the deviation between the calculated results and the actual values ​​is reduced. The dynamic offset of the vehicle body is directly calculated based solely on the attitude change of the vehicle body, enabling it to more accurately reflect the dynamic offset of the vehicle. Simultaneously, the device dynamically tests building clearances and can display in real time whether there is a risk of exceeding the limits for the dynamic offset.

[0004] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: A vehicle dynamic envelope detection device and method are provided, including a vehicle body and a laser scanner disposed on the front side of the vehicle body, as well as a front acquisition bracket and a rear acquisition bracket disposed on the bottom of the vehicle body. The laser scanner is used to acquire and obtain the point cloud map of the rail cross-section profile and the point cloud map of the clearance profile. Two first laser displacement sensors and two second laser displacement sensors are disposed on the front acquisition bracket. The first laser displacement sensors and the second laser displacement sensors are used to measure the three-dimensional coordinates of the gauge measurement point.

[0005] Furthermore, the front acquisition bracket and the rear acquisition bracket have the same structure. The front acquisition bracket includes a front side plate, a rear side plate, a top plate, a bottom plate, and two side plates. The front side plate, the rear side plate, the top plate, the bottom plate, and the two side plates are connected to form a detection and control cavity. Each side plate has a sensor side inclined plate for installing the first laser displacement sensor on its side.

[0006] Furthermore, two mounting plates are fixed to the top of the top plate.

[0007] Furthermore, the orientation of both the first and second laser displacement sensors is at a 35° angle to the rail, and the laser cross-sections of both sensors are perpendicular to the rail direction.

[0008] Furthermore, the laser scanner is a 360° laser scanner.

[0009] A detection method for a vehicle dynamic envelope detection device includes the following steps: S1: Establish the orbital coordinate system; specifically: Using the center point of the designed track gauge as the origin of the coordinate system The train runs in the direction parallel to the design rail top plane and along the longitudinal direction of the track centerline. The positive direction of the axis; transversely perpendicular to the track centerline within the designed rail top plane, with the right side of the car body as... The positive direction of the axis; vertically upwards, perpendicular to the design rail top plane. Positive direction of the axis; S2: Determine the three-dimensional coordinates of the track gauge measurement point and the laser displacement sensor at any given moment; specifically: S21: Define the lowest point of the rail top arc in the rail cross-sectional profile as the rail vertex. , track vertex The point 16mm below the track gauge is the track gauge measurement point. ; S22: Two first laser displacement sensors are used to obtain the track gauge measurement points of the front left rail and the front right rail, respectively. The three-dimensional coordinates at any given time are given by the first laser displacement sensor, which measures the track gauge of the left and right front rails. The coordinates are respectively , The two second laser displacement sensors are used to measure the track gauge of the left and right rear rails, respectively. The three-dimensional coordinates at any given time, assuming the track gauge measurement points of the left and right rear rails acquired by the second laser displacement sensor. The coordinates are respectively , ; S3: Based on real-time data collected from all distance measurement points by the first and second laser displacement sensors. The three-dimensional coordinates are obtained, and the front of the vehicle body is scanned by a laser scanner to obtain the point cloud of the rail cross-section profile and the point cloud of the building boundary profile; the data collected by the first laser displacement sensor, the second laser displacement sensor and the laser scanner are synchronized in real time. S4: Based on real-time collected coordinates Calculate the offset of the car body centerline relative to the track centerline, the lateral dynamic offset of any point at the front end of the car body, and the lateral dynamic offset of any point at the rear end of the car body. S5: Process the point cloud map of the rail cross-section profile and the point cloud map of the building clearance profile to obtain the actual building clearance profile; calculate the rail midpoint based on the rail cross-section profile to obtain the track centerline and obtain the actual building clearance profile; specifically: S6: Set the safety threshold between the vehicle envelope and the actual building clearance profile, based on the orbital coordinate system, using the maximum dynamic offset. The vehicle envelope is obtained by combining the static profile of the vehicle. The vehicle envelope and the actual building clearance profile are both imported into the track coordinate system with the track centerline as the reference, and the vehicle envelope is dynamically judged to determine whether it encroaches on the line.

[0010] Furthermore, in step S3, the specific steps are as follows: S31: Controls the vehicle to travel at a constant speed along the track, and records the vehicle's speed in real time via an odometer or on-board positioning device. Axis coordinates; S32: The distance to the measurement point is collected in real time using the first laser displacement sensor and the second laser displacement sensor. The three-dimensional coordinates are stored synchronously with timestamps, recording the coordinates at each acquisition moment. ; S33: By scanning the space in front of and on both sides of the vehicle body with a laser scanner, point cloud maps of the rail cross-section profile and building clearance profile are simultaneously acquired;

[0011] Furthermore, in step S4, the specific steps are as follows: S41: Based on real-time collected coordinates Calculate the offset of the vehicle centerline relative to the track centerline at any given time: ; ; ; ; ; ; In the formula, This refers to the lateral displacement of the front end of the car body relative to the rail. This represents the vertical displacement of the left side of the car body relative to the rail. This refers to the lateral displacement of the rear end of the vehicle body relative to the rail. This refers to the vertical displacement of the right side of the vehicle body relative to the rail. This refers to the yaw angle of the vehicle body relative to the track. The roll angle of the vehicle body relative to the track. The distance between the measurement points of the first laser displacement sensor and the second laser displacement sensor is [missing information]. The distance between adjacent first laser displacement sensors or the distance between adjacent second laser displacement sensors; S42: Based on the yaw angle of the car body relative to the track Roll angle relative to the track Calculate the lateral dynamic offset of any point at the front of the vehicle body relative to the reference coordinates and the lateral dynamic offset of any point at the rear of the vehicle body relative to the reference coordinates; specifically: Lateral dynamic offset at any point on the front of the vehicle body The calculation method is as follows: ; Lateral dynamic offset at any point at the rear of the vehicle body The calculation method is as follows: ; In the formula, This refers to the lateral displacement of the vehicle body. The distance from the center of the vehicle body. The distance from the center of the vehicle body to the orbital coordinate system is the height. To represent the height of any point on the vehicle body relative to the track coordinate system; S43: Lateral dynamic offset of any point at the front of the vehicle body during all data acquisition times. Lateral dynamic offset of any point at the rear of the vehicle body And take the horizontal dynamic offset. Absolute value and lateral dynamic offset The maximum value among the absolute values ​​yields the maximum dynamic offset. .

[0012] Furthermore, in step S5, the specific steps are as follows: S51: Extract the profiles from the point cloud map of the rail cross-section and the point cloud map of the building clearance to obtain the rail cross-section profile and the building clearance profile; S52: Obtain the coordinates of the gauge points corresponding to the left and right rails based on the rail apex of the rail cross-section profile. The coordinates of the two gauge points are as follows: and According to the track gauge point coordinates and track gauge points Calculate the coordinates of the rail midpoint The centerline of the track is determined; the formula for calculating the midpoint of the rail is as follows: The formula for calculating the midpoint of the rail is as follows: ; S53: Based on the determined track centerline, calculate the points in the point cloud diagram of the building clearance outline. The actual position of the building boundary profile point cloud in the orbital coordinate system is obtained by measuring the actual distance relative to the orbital centerline. All building boundary profile point clouds at the actual positions are then connected to construct the actual building boundary profile in the orbital coordinate system.

[0013] Furthermore, in step S6, the specific steps are as follows: If the vehicle envelope intersects with the actual building clearance outline, it is determined that the maximum envelope of the vehicle body has encroached on the boundary. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is less than or equal to the safety threshold, then it is determined that the maximum envelope of the vehicle body does not infringe on the line. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is greater than the safety threshold, then a collision warning is issued for the maximum vehicle envelope.

[0014] The beneficial effects of this invention are as follows: The vehicle dynamic envelope detection device of the present invention comprises two sets of high-speed 2D digital laser displacement sensors, a 360° scanner, and a data acquisition and analysis circuit. The sensor arrangement is as follows: the 2D sensors are at a 35° angle to the rail, the laser cross-section is perpendicular to the rail direction, and the measurement range is ensured to be the rail top and rail shoulder. The 360° scanner is fixed at the front end of the vehicle body, parallel to the horizontal plane, to ensure that the laser can measure surrounding buildings and equipment.

[0015] This invention offers a simple measurement method that avoids complex mathematical expressions and parameter estimations. It directly calculates the vehicle's dynamic offset based on its attitude changes, resulting in simple calculations and reliable results. Simultaneously, it dynamically tests building clearances and displays whether the dynamic offset poses a risk of exceeding limits.

[0016] This invention dynamically calculates the vehicle body's dynamic offset across the entire track, covering the impact of track conditions, weather, and crosswind conditions on the vehicle body's offset. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the overall structure of the present invention. Figure 2 ; Figure 3 This is a rear view of the present invention; Figure 4 This is the left view of the present invention; Figure 5 This is a schematic diagram of the overall structure of the front acquisition support; Figure 6 This is a schematic diagram of the internal structure of the front acquisition support; Figure 7 A schematic diagram illustrating the establishment of the orbital coordinate system; Figure 8 Schematic diagram of rail cross-section measurement using a laser displacement sensor Figure 1 ; Figure 9 Schematic diagram of rail cross-section measurement using a laser displacement sensor Figure 2 ; Figure 10 This is a schematic diagram of the vehicle body moving laterally; Figure 11 This is a schematic diagram of the vehicle's side roll. Figure 12 This is a schematic diagram of the vehicle body turning around; Figure 13 Point cloud diagrams of rail cross-sectional profile and clearance contour; Figure 14 Point cloud diagram of the rail cross-section profile; Figure 15 This is a schematic diagram of the coordinates of the track gauge points; Figure 16 A schematic diagram for determining the vehicle envelope and equipment clearance contour; The symbols for the main components in the diagram are explained below: 1. Vehicle body; 2. Front acquisition bracket; 21. Front side plate; 22. Rear side plate; 23. Top plate; 24. Bottom plate; 25. Side plate; 26. Sensor side inclined plate; 27. Mounting plate; 28. Signal module mounting base; 29. ​​Inertial navigation system; 3. Rear acquisition bracket; 4. First laser displacement sensor; 5. Second laser displacement sensor; 6. Laser scanner; 7. Track. Detailed Implementation

[0018] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0019] like Figure 1 ,2 As shown in Figures 3 and 4, the vehicle dynamic envelope detection device includes a vehicle body 1 and a laser scanner 6 mounted on the front side of the vehicle body 1. The laser scanner 6 is preferably a 360° laser scanner. A front acquisition bracket 2 and a rear acquisition bracket 3 are mounted on the bottom of the vehicle body 1. The laser scanner 6 is used to acquire and obtain the point cloud map of the rail cross-section profile and the point cloud map of the clearance profile. Two first laser displacement sensors 4 and two second laser displacement sensors 5 are mounted on the front acquisition bracket 2. The first laser displacement sensors 4 and the second laser displacement sensors 5 are used to measure the three-dimensional coordinates of the gauge measurement points.

[0020] like Figure 5 and 6 As shown, the front acquisition bracket 2 and the rear acquisition bracket 3 have the same structure. The front acquisition bracket 2 includes a front side plate 21, a rear side plate 22, a top plate 23, a bottom plate 24, and two side plates 25. The front side plate 21, rear side plate 22, top plate 23, bottom plate 24, and two side plates 25 are connected to form a detection and control cavity. Each side plate 25 has a sensor-side inclined plate 26 for mounting the first laser displacement sensor 4 on its side. Two mounting plates 27 are fixed to the top of the top plate 23 for mounting and docking with the vehicle body 1. The orientation of the first laser displacement sensor 4 and the second laser displacement sensor 5 is at a 35° angle to the rail, and the laser cross-sections of the first laser displacement sensor 4 and the second laser displacement sensor 5 are perpendicular to the rail direction. A signal processing module and an inertial navigation system 29 are installed in the detection and control cavity. A signal module mounting base 28 for mounting the signal module is also installed in the detection and control cavity. The signal processing module can preferably be a CSRT2300, and the inertial navigation system 29 can preferably be an INS950. The red area in the figure represents the laser scanning area of ​​the first laser displacement sensor 4 and the second laser displacement sensor 5.

[0021] A detection method for a vehicle dynamic envelope detection device includes the following steps: S1: As Figure 7 As shown, establish the orbital coordinate system; specifically: Using the center point of the designed track gauge as the origin of the coordinate system The train runs in the direction parallel to the design rail top plane and along the longitudinal direction of the track centerline. The positive direction of the axis; transversely perpendicular to the track centerline within the designed rail top plane, with the right side of the car body as... The positive direction of the axis; vertically upwards, perpendicular to the design rail top plane. Positive direction of the axis; S2: As Figure 8 and 9 As shown, the three-dimensional coordinates of the track gauge measurement point and the laser displacement sensor at any given moment are determined; Figure 8In the diagram, the horizontal axis represents the width of the rail section, the vertical axis represents the height of the rail section, and the highest point is the zero point of the vertical axis. Figure 9 In the diagram, the horizontal axis represents the width of the rail section, and the vertical axis represents the height of the rail section. Point E is the zero point, and point F is located on the inner shoulder of the rail below point E, at a vertical height of 16mm from point E. Specifically: S21: Define the lowest point of the rail top arc in the rail cross-sectional profile as the rail vertex. , track vertex The point 16mm below the track gauge is the track gauge measurement point. ; S22: Two first laser displacement sensors 4 are used to obtain the track gauge measurement points of the front left rail and the front right rail, respectively. The three-dimensional coordinates at any given time, assuming the track gauge measurement points of the front left rail and front right rail acquired by the first laser displacement sensor 4. The coordinates are respectively , The two second laser displacement sensors 5 are used to measure the track gauge of the left and right rear rails, respectively. The three-dimensional coordinates at any given time, assuming the gauge measurement points of the rear left and rear right rails acquired by the second laser displacement sensor 5. The coordinates are respectively , ; S3: Based on the real-time acquisition of all distance measurement points by the first laser displacement sensor 4 and the second laser displacement sensor 5 The three-dimensional coordinates are obtained, and the front of the vehicle body is scanned by laser scanner 6 to obtain the point cloud of the rail cross-section profile and the point cloud of the building clearance profile; the data collected by the first laser displacement sensor 4, the second laser displacement sensor 5 and the laser scanner 6 are synchronized in real time; specifically: S31: Control the vehicle body 1 to move at a constant speed along the track, and record the vehicle body's speed in real time through an odometer or on-board positioning device. Axis coordinates; S32: The distance to the measurement point is collected in real time using the first laser displacement sensor 4 and the second laser displacement sensor 5. The three-dimensional coordinates are stored synchronously with timestamps, recording the coordinates at each acquisition moment. ; S33: The laser scanner 6 scans the space in front of and on both sides of the vehicle body, and simultaneously collects point cloud maps of the rail cross-section profile and building clearance profile. S4: Based on real-time collected coordinates Calculate the offset of the car body centerline relative to the track centerline, the lateral dynamic offset of any point at the front of the car body, and the lateral dynamic offset of any point at the rear of the car body; specifically: Figure 10This is a schematic diagram of the lateral movement of the vehicle body, representing the lateral offset of the vehicle body relative to the center of the track during operation. Figure 11 This is a schematic diagram of vehicle roll, illustrating the vertical rotation of the vehicle body relative to its center of gravity during operation. Figure 12 This is a diagram illustrating the vehicle body's head-shaking motion, indicating that the front and rear ends of the vehicle body rotate relative to the center of the vehicle body during operation. S41: As Figure 10 , 11 As shown in Figure 12, based on the coordinates collected in real time Calculate the offset of the vehicle centerline relative to the track centerline at any given time: ; ; ; ; ; ; In the formula, This refers to the lateral displacement of the front end of the car body 1 relative to the rail. This represents the vertical displacement of the left side of car body 1 relative to the rail. This refers to the lateral displacement of the rear end of car body 1 relative to the rail. This represents the vertical displacement of the right side of car body 1 relative to the rail. Let be the yaw angle of car body 1 relative to the track. Let be the roll angle of car body 1 relative to the track. The distance between the measuring point of the first laser displacement sensor 4 and the measuring point of the second laser displacement sensor 5. The distance between adjacent first laser displacement sensors 4 or adjacent second laser displacement sensors 5; S42: Based on the yaw angle of car body 1 relative to the track Roll angle of the car body relative to the track Calculate the lateral dynamic offset of any point at the front end of vehicle body 1 relative to the reference coordinates and the lateral dynamic offset of any point at the rear end of vehicle body 1 relative to the reference coordinates; specifically: Lateral dynamic offset at any point on the front of the vehicle body The calculation method is as follows: ; Lateral dynamic offset at any point at the rear of the vehicle body The calculation method is as follows: ; In the formula, This refers to the lateral displacement of the vehicle body. The distance from the center of the vehicle body. The distance from the center of the vehicle body to the orbital coordinate system is the height. To represent the height of any point on the vehicle body relative to the track coordinate system; S43: Lateral dynamic offset of any point at the front of the vehicle body during all data acquisition times. Lateral dynamic offset of any point at the rear of the vehicle body And take the horizontal dynamic offset. Absolute value and lateral dynamic offset The maximum value among the absolute values ​​yields the maximum dynamic offset. ; S5: Process the point cloud map of the rail cross-section profile and the point cloud map of the building clearance profile to obtain the actual building clearance profile; calculate the rail midpoint based on the rail cross-section profile to obtain the track centerline and obtain the actual building clearance profile; specifically: S51: Extract the profiles from the point cloud map of the rail cross-section and the point cloud map of the building clearance to obtain the rail cross-section profile and the building clearance profile; S52: Obtain the coordinates of the gauge points corresponding to the left and right rails based on the rail apex of the rail cross-section profile. The coordinates of the two gauge points are as follows: and According to the track gauge point coordinates and track gauge points Calculate the coordinates of the rail midpoint The centerline of the track is determined; the formula for calculating the midpoint of the rail is as follows: The formula for calculating the midpoint of the rail is as follows: ; S53: As Figure 13 , 14 And 15, based on the determined track centerline, calculate the points in the building clearance outline point cloud map. The actual position of the building boundary profile point cloud in the orbital coordinate system is obtained by the actual distance relative to the orbital centerline. All building boundary profile point clouds at the actual positions are then connected to construct the actual building boundary profile in the orbital coordinate system. Figure 13 The point cloud map shows the rail profile and clearance contour, representing the point cloud of the current tunnel section tested by the 360 ​​scanner, which includes the rail profile and the tunnel section. Figure 14 This is a point cloud diagram of the rail cross-section profile, representing... Figure 15 The diagram shows the coordinates of the gauge point, which is the rail profile section obtained by a 360 scanner at the point 16mm away from the top of the rail on the working side of the rail. S6: As Figure 16 As shown, a safety threshold is set between the vehicle envelope and the actual building clearance profile. Based on the orbital coordinate system, this is achieved through the maximum dynamic offset. The vehicle envelope is obtained by combining the static profile of the vehicle. The vehicle envelope and the actual building clearance profile are both imported into the track coordinate system with the track centerline as the reference, and the vehicle envelope is dynamically judged to determine whether it encroaches on the line. Figure 15 This is a schematic diagram of the track gauge coordinates, representing a point on the working edge of the rail, 16mm from the top of the rail. Specifically: If the vehicle envelope intersects with the actual building clearance outline, it is determined that the maximum envelope of the vehicle body has encroached on the boundary. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is less than or equal to the safety threshold, then it is determined that the maximum envelope of the vehicle body does not infringe on the line. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is greater than the safety threshold, then a collision warning is issued for the maximum vehicle envelope.

Claims

1. A method for detecting the dynamic envelope of a vehicle, comprising a detection device, the detection device comprising a vehicle body (1) and a laser scanner (6) disposed on the front side of the vehicle body (1), and a front acquisition bracket (2) and a rear acquisition bracket (3) disposed on the bottom of the vehicle body (1), wherein the laser scanner (6) is used to acquire and obtain the point cloud map of the rail cross-section profile and the point cloud map of the building clearance profile; the front acquisition bracket (2) is provided with two first laser displacement sensors (4), and the rear acquisition bracket (3) is provided with two second laser displacement sensors (5), wherein the first laser displacement sensors (4) and the second laser displacement sensors (5) measure the three-dimensional coordinates of the gauge measurement point; Its features are: The detection method includes the following steps: S1: Establish the orbital coordinate system; specifically: Using the center point of the designed track gauge as the origin of the coordinate system The train runs in the direction parallel to the design rail top plane and along the longitudinal direction of the track centerline. The positive direction of the axis; transversely perpendicular to the track centerline within the designed rail top plane, with the right side of the car body as... The positive direction of the axis; vertically upwards, perpendicular to the design rail top plane. Positive direction of the axis; S2: Determine the three-dimensional coordinates of the track gauge measurement point relative to the first laser displacement sensor (4) and the second laser displacement sensor (5) at any given moment; specifically: S21: Define the lowest point of the rail top arc in the rail cross-sectional profile as the rail vertex. , track vertex The point 16mm below the track gauge is the track gauge measurement point. ; S22: Two first laser displacement sensors (4) are used to obtain the track gauge measurement points of the front left rail and the front right rail, respectively. The three-dimensional coordinates at any given time, assuming the track gauge measurement points of the front left rail and front right rail obtained by the first laser displacement sensor (4). The coordinates are respectively , Two second laser displacement sensors (5) are used to measure the track gauge of the left and right rear rails, respectively. The three-dimensional coordinates at any given time, assuming the track gauge measurement points of the rear left rail and rear right rail obtained by the second laser displacement sensor (5). The coordinates are respectively , ; S3: All track gauge measurement points collected in real time based on the first laser displacement sensor (4) and the second laser displacement sensor (5) The three-dimensional coordinates are obtained, and the front of the vehicle body is scanned by the laser scanner (6) to obtain the point cloud map of the rail cross section profile and the point cloud map of the building clearance profile; the data collected by the first laser displacement sensor (4), the second laser displacement sensor (5) and the laser scanner (6) are synchronized in real time. S4: Based on real-time collected coordinates The following steps are taken to calculate the offset of the car body centerline relative to the track centerline, the lateral dynamic offset of any point at the front of the car body, and the lateral dynamic offset of any point at the rear of the car body: S41: Based on real-time collected coordinates Calculate the offset of the vehicle centerline relative to the track centerline at any given time: ； ； ； ； ； ； In the formula, The lateral displacement of the front end of the car body (1) relative to the rail. The vertical displacement of the left side of the car body (1) relative to the rail. The lateral displacement of the rear end of the car body (1) relative to the rail. The vertical displacement of the right side of the car body (1) relative to the rail. The yaw angle of the car body (1) relative to the track, The roll angle of the car body (1) relative to the track. The distance between the measuring point of the first laser displacement sensor (4) and the measuring point of the second laser displacement sensor (5) is... The distance between adjacent first laser displacement sensors (4) or adjacent second laser displacement sensors (5); S42: Based on the yaw angle of the car body (1) relative to the track Roll angle of the car body (1) relative to the track Calculate the lateral dynamic offset of any point at the front end of the vehicle body (1) relative to the reference coordinates and the lateral dynamic offset of any point at the rear end of the vehicle body relative to the reference coordinates; specifically: Lateral dynamic offset at any point on the front of the vehicle body The calculation method is as follows: ； Lateral dynamic offset at any point at the rear of the vehicle body The calculation method is as follows: ； In the formula, This refers to the lateral displacement of the vehicle body. The distance from the center of the vehicle body. The distance from the center of the vehicle body to the orbital coordinate system is the height. To represent the height of any point on the vehicle body relative to the track coordinate system; S43: Lateral dynamic offset of any point at the front of the vehicle body during all data acquisition times. Lateral dynamic offset of any point at the rear of the vehicle body And take the horizontal dynamic offset. Absolute value and lateral dynamic offset The maximum value among the absolute values ​​yields the maximum dynamic offset. ; S5: Process the point cloud map of the rail cross-section profile and the point cloud map of the building clearance profile to obtain the actual building clearance profile; calculate the rail midpoint based on the rail cross-section profile to obtain the track centerline and obtain the actual building clearance profile. S6: Set the safety threshold between the vehicle envelope and the actual building clearance profile, based on the orbital coordinate system, using the maximum dynamic offset. The vehicle envelope is obtained by combining the static profile of the vehicle. The vehicle envelope and the actual building clearance profile are both imported into the track coordinate system with the track centerline as the reference, and the vehicle envelope is dynamically judged to determine whether it encroaches on the line.

2. The vehicle dynamic envelope detection method according to claim 1, characterized in that, The front acquisition bracket (2) and the rear acquisition bracket (3) have the same structure. The front acquisition bracket (2) includes a front side plate (21), a rear side plate (22), a top plate (23), a bottom plate (24) and two side plates (25). The front side plate (21), the rear side plate (22), the top plate (23), the bottom plate (24) and the two side plates (25) are connected to form a detection control cavity. Each side plate (25) is provided with a sensor side inclined plate (26) for installing the first laser displacement sensor (4).

3. The vehicle dynamic envelope detection method according to claim 2, characterized in that, The top plate (23) has two mounting plates (27) fixed to its top.

4. The vehicle dynamic envelope detection method according to claim 3, characterized in that, The orientation of the first laser displacement sensor (4) and the second laser displacement sensor (5) is at a 35° angle to the rail, and the laser cross-sections of the first laser displacement sensor (4) and the second laser displacement sensor (5) are perpendicular to the rail direction.

5. The vehicle dynamic envelope detection method according to claim 4, characterized in that, The laser scanner (6) is a 360° laser scanner.

6. The vehicle dynamic envelope detection method according to claim 1, characterized in that, In step S3, the specific steps are as follows: S31: Control the vehicle body (1) to move at a constant speed along the track, and record the vehicle body's speed in real time through an odometer or on-board positioning device. Axis coordinates; S32: Track gauge measurement points acquired in real time using the first laser displacement sensor (4) and the second laser displacement sensor (5) The three-dimensional coordinates are stored synchronously with timestamps, recording the coordinates at each acquisition moment. ; S33: Scan the space in front of and on both sides of the vehicle body using a laser scanner (6) to simultaneously collect point cloud maps of the rail cross-section profile and the building clearance profile.

7. The vehicle dynamic envelope detection method according to claim 1, characterized in that, In step S5, the specific steps are as follows: S51: Extract the profiles from the point cloud map of the rail cross-section and the point cloud map of the building clearance to obtain the rail cross-section profile and the building clearance profile; S52: Obtain the coordinates of the gauge points corresponding to the left and right rails based on the rail apex of the rail cross-section profile. The coordinates of the two gauge points are as follows: and According to the track gauge point coordinates and track gauge points Calculate the coordinates of the rail midpoint The centerline of the rail is determined; the formula for calculating the midpoint of the rail is as follows: ； S53: Based on the determined track centerline, calculate the points in the point cloud diagram of the building clearance outline. The actual distance relative to the centerline of the track. The actual position of the building boundary profile point cloud in the orbital coordinate system is obtained, and all the building boundary profile point clouds at the actual positions are connected to construct the actual building boundary profile in the orbital coordinate system.

8. The vehicle dynamic envelope detection method according to claim 1, characterized in that, In step S6, the specific steps are as follows: If the vehicle envelope intersects with the actual building clearance outline, it is determined that the maximum envelope of the vehicle body has encroached on the boundary. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is less than or equal to the safety threshold, then it is determined that the maximum envelope of the vehicle body does not infringe on the line. If the vehicle envelope does not intersect with the actual building clearance outline, and the minimum lateral clearance between the vehicle envelope and the actual building clearance outline is greater than the safety threshold, then a collision warning is issued for the maximum vehicle envelope.

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