A non-contact pantograph motion status monitoring device and method resistant to sunlight

Abstract

This invention discloses a non-contact pantograph motion status monitoring device resistant to sunlight, comprising multiple ultraviolet fluorescent targets mounted on the pantograph, an industrial control computer, a binocular measurement module, and an ultraviolet lamp mounted on the vehicle roof for illuminating the fluorescent targets. The binocular measurement module is used for image acquisition of the ultraviolet fluorescent targets and for tracking and identifying the position of the target center. When the ultraviolet lamp's light intensity is insufficient, it irradiates the ultraviolet fluorescent targets of the pantograph with ultraviolet light, causing the fluorescent targets to illuminate and cooperate with the binocular measurement module to complete image acquisition. The industrial control computer is used to process the images acquired by the binocular measurement module, and when the average pixel value of the target is lower than a threshold, it controls the ultraviolet lamp to be turned on.

Description

Technical Field

[0001] This invention relates to a non-contact pantograph motion status monitoring device and method that resists sunlight, belonging to the field of rail transit status detection technology. Background Technology

[0002] The pantograph is the primary current-collecting device for electrified traction vehicles such as high-speed trains, electric locomotives, and subways. When the vehicle is moving at high speed, the pantograph is affected by multiple forces, including the vehicle's traction force, the pressure of the overhead contact line, the lift force of the pantograph, and air resistance, resulting in various movements such as swaying, which affect the pantograph-catenary contact state. When the pantograph's movement changes drastically, it can easily lead to poor pantograph-catenary contact, causing excessive pull-out, arcing in the pantograph-catenary gap, and instability in the mechanical support structure. Therefore, during high-speed train operation, it is necessary to dynamically monitor the pantograph's dynamic parameters, such as speed magnitude, speed direction, acceleration, and deformation, online.

[0003] Currently, the main measurement method involves installing acceleration or pressure sensors on the pantograph. However, since the pantograph carries a high voltage during normal operation, this can affect the sensor's electrical signal. Therefore, sensors without electrical or optical signal transmission, such as fiber optic grating sensors, are generally chosen. Furthermore, installing sensors on the pantograph and transmitting the data via fiber optic cable to the locomotive requires significant modifications to the pantograph, affecting its aerodynamic shape and creating safety hazards such as vibration and detachment. Therefore, the demand for non-contact measurement for pantograph monitoring is increasing. Currently, existing vehicle-mounted catenary operation status monitoring devices (3C) provide non-contact observation of the pantograph-catenary contact, but only offer observation and monitoring functions and cannot measure the pantograph's dynamic motion parameters. Additionally, because the observation camera observes the sky, it is susceptible to interference from changes in skylight, including photoelectric interference during tunnel entry and exit. Summary of the Invention

[0004] The purpose of this invention is to provide a non-contact pantograph motion status monitoring device and method that is resistant to sunlight, so as to solve the shortcomings of existing vehicle-mounted catenary operation status detection devices (3C) that perform non-contact observation of pantograph-catenary contact, but only provide observation and monitoring functions and cannot measure the dynamic motion parameters of the pantograph.

[0005] A non-contact pantograph motion status monitoring device resistant to sunlight includes multiple ultraviolet fluorescent targets on the pantograph, an industrial control computer, a binocular measurement module, and an ultraviolet lamp installed on the roof of the vehicle to make the ultraviolet fluorescent targets emit light.

[0006] The binocular measurement module is used to acquire images of ultraviolet fluorescent targets and to track and identify the position of the target center.

[0007] When the ultraviolet lamp is insufficient, it irradiates ultraviolet light onto the ultraviolet fluorescent target of the pantograph to make the fluorescent target emit light, which, together with the binocular measurement module, completes image acquisition.

[0008] The industrial control computer is used to process the images acquired by the binocular measurement module. When the average pixel value of the target point is lower than the threshold, it controls the ultraviolet lamp to be turned on.

[0009] Furthermore, the target point is characterized by a circular, triangular, polygonal, or cross-shaped shape.

[0010] Furthermore, the target point is located at the horn or at 1 / 4 or 3 / 4 of the center of the pantograph.

[0011] Furthermore, the binocular measurement module consists of two industrial cameras.

[0012] Furthermore, the binocular measurement module uses a tracking algorithm to track, identify, and measure the position of the target center.

[0013] Furthermore, the binocular measurement module uses the pixel centroid method to acquire images of ultraviolet fluorescent targets.

[0014] A monitoring method for a non-contact pantograph motion status monitoring device resistant to sunlight, the method comprising:

[0015] The binocular measurement module is calibrated using a visual measurement model to obtain the binocular measurement visual model parameters, and the measurement and calculation of the 3D coordinates of the target position are completed.

[0016] The target image is detected and identified by a binocular measurement module. The target is continuously tracked and detected using a tracking algorithm. The position of the target center is measured. Based on the change of position over time, the dynamic motion parameters of the pantograph are calculated to monitor the movement state of the pantograph. When the tracked target is lost, the average pixel value of the target area is judged. When it is lower than the average pixel value, the ultraviolet lamp is controlled to provide supplementary lighting.

[0017] Furthermore, the calculation of the pantograph's dynamic motion parameters includes:

[0018] Based on the target position tracking results, the center coordinates of the target points are extracted using the pixel centroid method. A binocular vision measurement model is then used to measure the 3D coordinates of the centers of all target points. Let the 3D coordinates of the center of the i-th target point at time k be [xi, yi, zi]. k Then calculate the velocity of the point at time k-1:

[0019] v k-1 =||[xi,yi,zi] k -[xi,yi,zi] k-1 ||·f

[0020] The directions are: [xi,yi,zi] k -[xi,yi,zi] k-1

[0021] The acceleration is: a k-1 =(v k-1 -v k-2 )·f, where f is the frame rate of image acquisition.

[0022] Furthermore, the method for determining the average pixel value of the target area and controlling the ultraviolet lamp to provide supplementary illumination when the average pixel value is lower than the average pixel value includes:

[0023] When the average pixel value of a target point is lower than the threshold T, the ultraviolet lamp is turned on to illuminate the pantograph. When the average pixel value outside the target point in the pantograph area is greater than the threshold T / 2, the ultraviolet lamp is turned off.

[0024] Determine if the average pixel value of the target is lower than T. If it is lower than T, continue to turn on the UV lamp for a fixed time S, and then repeat the detection. When the average pixel value of the target reaches or exceeds T after the UV lamp is turned off, the UV lamp remains off.

[0025] Furthermore, the tracking algorithm includes:

[0026] First, the initial position of the target point is detected on the image using an image template matching algorithm. The image template is defined according to the shape of the target point used.

[0027] After detecting the initial position, the Kernelized Correlation Filter algorithm is used to complete the subsequent rapid tracking of the target position.

[0028] Compared with the prior art, the beneficial effects achieved by this invention are as follows: This method uses binocular vision to measure and monitor the dynamic motion parameters of the pantograph, truly realizing non-contact measurement, without affecting the aerodynamic shape of the pantograph, and with minimal safety hazards; at the same time, by utilizing ultraviolet fluorescent targets, interference from sunlight is avoided, truly achieving real-time measurement in all weather conditions. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the device of the present invention. Detailed Implementation

[0030] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0031] Example 1

[0032] like Figure 1As shown, a non-contact pantograph motion status monitoring device resistant to sunlight is disclosed, including multiple ultraviolet fluorescent target points 1 set on the pantograph 2, an industrial control computer 3, a binocular measurement module 5, and an ultraviolet lamp 4 set on the roof of the vehicle for emitting light from the ultraviolet fluorescent target points 1.

[0033] The binocular measurement module is used to acquire images of ultraviolet fluorescent targets and to track and identify the position of the target center.

[0034] When the ultraviolet lamp is insufficient, it irradiates ultraviolet light onto the ultraviolet fluorescent target of the pantograph to make the fluorescent target emit light, which, together with the binocular measurement module, completes image acquisition.

[0035] The industrial control computer is used to process the images acquired by the binocular measurement module. When the average pixel value of the target point is lower than the threshold, it controls the ultraviolet lamp to be turned on.

[0036] Specifically, the device involves deploying multiple ultraviolet fluorescent targets on the pantograph. The shapes of these targets can be set to circular, triangular, polygonal, etc., as needed. A binocular measurement module, composed of two industrial cameras and deployed on the roof of the vehicle, is used to photograph and measure the ultraviolet fluorescent targets on the pantograph. The 3D coordinates of the center of the ultraviolet fluorescent target are obtained through binocular vision principles.

[0037] Calculate the instantaneous velocity and acceleration based on the change of the target center coordinates over time;

[0038] An ultraviolet lamp is deployed on the roof of the vehicle. When the industrial camera detects that the amount of light emitted by the ultraviolet fluorescent target is insufficient, that is, when the long-wave ultraviolet light in the sunlight is low or when driving in a dark environment such as a tunnel, the ultraviolet lamp irradiates the ultraviolet fluorescent target of the pantograph with ultraviolet light, causing the fluorescent target to emit light. The binocular measurement module continues to complete the measurement and calculation tasks.

[0039] The binocular measurement module detects ultraviolet fluorescence targets in two steps: target detection and recognition, and tracking and extraction.

[0040] At the start of operation, two industrial cameras take pictures of the pantograph. Based on the predetermined shape of the target point, such as a circle, triangle, or polygon, the target point image is detected and identified. Subsequently, a tracking algorithm is used to continuously track and detect the target point, and the pixel centroid method is used to extract features from the target point center. If the tracked target is lost, the detection and identification process is repeated to relocate the target. During tracking and extraction, the average pixel value of the target point area is judged in real time, and a threshold T is set. When the average pixel value is lower than T, ultraviolet lamps are controlled to provide supplemental lighting.

[0041] Example 2

[0042] This invention also proposes a non-contact pantograph motion status monitoring method resistant to sunlight, the specific steps of which are as follows:

[0043] (1) Deploy several ultraviolet fluorescent material targets on the pantograph. The targets have obvious characteristic shapes, such as circles, triangles, polygons, crosses, etc., and can be deployed at the horn, the center of the pantograph, or at 1 / 4 or 3 / 4 of the pantograph.

[0044] (2) Two visible light industrial cameras are used to form a binocular measurement module, which is deployed on the roof of the vehicle to observe the pantograph and can clearly see the ultraviolet fluorescent target.

[0045] (3) The binocular measurement module is calibrated with a visual measurement model to obtain the binocular measurement visual model parameters, which can complete the measurement and calculation of the 3D coordinates of the target position;

[0046] (4) Deploying ultraviolet lamps on the roof of the vehicle can irradiate all ultraviolet fluorescent targets with ultraviolet light, enabling the fluorescent targets to emit light;

[0047] (5) An industrial control computer is deployed inside the locomotive to acquire and process images from the binocular measurement module and perform image processing calculations; at the same time, it is used to control the opening and closing of the ultraviolet lamps;

[0048] (6) When working, turn on the ultraviolet lamp to make the fluorescent target point glow. The binocular measurement module continuously takes pictures of the pantograph at a predetermined frame rate, set the frame rate to f. By performing target detection and recognition on the fluorescent target point in the image, locate the position of all target points. Turn off the ultraviolet lamp and the tracking algorithm completes the subsequent target point tracking and recognition.

[0049] (7) Extract the center coordinates of the target points using the pixel centroid method, and use a binocular measurement vision model to complete the 3D coordinate measurement of the center of all target points. Let the 3D coordinates of the center of the i-th target point at the k-th frame be [xi,yi,zi]. k Then calculate the velocity of that point at time k-1:

[0050] v k-1 =||[xi,yi,zi] k -[xi,yi,zi] k-1 ||·f

[0051] The directions are: [xi,yi,zi] k -[xi,yi,zi] k-1

[0052] The acceleration is: a k-1 =(v k-1 -v k-2 )·f, where f is the frame rate of image acquisition.

[0053] (8) Simultaneously, each industrial camera calculates the average pixel size of each target area. When the average pixel value of a target is lower than the threshold T, the ultraviolet lamp is turned on to illuminate the pantograph. When the average pixel value outside the target area of ​​the pantograph is greater than the threshold T / 2, the ultraviolet lamp is turned off. It is then determined whether the average pixel value of the target is lower than T. If it is lower than T, the ultraviolet lamp is turned on again and maintained for a fixed time S. The detection is then repeated. When the average pixel value of the target reaches or exceeds T after the ultraviolet lamp is turned off, the ultraviolet lamp remains off.

[0054] (9) When the system is working normally, repeat (5)-(7) to complete the measurement and calculation of dynamic motion parameters such as velocity, acceleration, and position of all target points of the pantograph during train operation.

[0055] In this embodiment, the tracking algorithm includes:

[0056] First, the initial position of the target point is detected on the image using an image template matching algorithm. The image template is defined according to the shape of the target point, such as a circular template, a triangular template, or a cross template.

[0057] After detecting the initial position, the Kernelized Correlation Filter algorithm is used to complete the subsequent rapid tracking of the target position.

[0058] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for monitoring the movement status of a non-contact pantograph resistant to sunlight, characterized in that, The method includes: The binocular measurement module is calibrated using a visual measurement model to obtain the binocular measurement visual model parameters, and the measurement and calculation of the 3D coordinates of the target position are completed. The target image is detected and identified by a binocular measurement module. The target is continuously tracked and detected by a tracking algorithm to complete the position measurement of the target center. Based on the position change over time, the dynamic motion parameters of the pantograph are calculated to monitor the movement state of the pantograph. When the tracked target is lost, the average pixel value of the target area is judged. When it is lower than the average pixel value, the ultraviolet lamp is controlled to provide supplementary lighting. The calculation of the pantograph's dynamic motion parameters includes: Based on the target position tracking results, the center coordinates of the target points are extracted using the pixel centroid method. A binocular vision measurement model is then used to measure the 3D coordinates of the centers of all target points. Let the 3D coordinates of the center of the i-th target point at time k be [xi, yi, zi]. k Then calculate the velocity of the point at time k-1: ; The direction is: ; The acceleration is: Where f is the frame rate of image acquisition; The method for determining the average pixel value of the target area and controlling the ultraviolet lamp to provide supplementary illumination when it is lower than the average pixel value includes: When the average pixel value within a target point is lower than the threshold T, the ultraviolet lamp is turned on to illuminate the pantograph. When the average pixel value outside the target point within the pantograph area is greater than the threshold T / 2, the ultraviolet lamp is turned off. Determine if the average pixel value of the target is lower than T. If it is lower than T, continue to turn on the UV lamp for a fixed time S, and then repeat the detection. When the average pixel value of the target reaches or exceeds T after the UV lamp is turned off, the UV lamp remains off.

2. The method for monitoring the movement status of a non-contact pantograph resisting sunlight according to claim 1, characterized in that, Tracking algorithms include: First, the initial position of the target point is detected on the image using an image template matching algorithm. The image template is defined according to the shape of the target point used. After detecting the initial position, the Kernelized Correlation Filter algorithm is used to complete the subsequent rapid tracking of the target position.

3. A non-contact pantograph motion status monitoring device based on the method of any one of claims 1-2, characterized in that, It includes multiple ultraviolet fluorescent targets mounted on the pantograph, an industrial control computer, a binocular measurement module, and an ultraviolet lamp mounted on the roof of the vehicle to make the ultraviolet fluorescent targets emit light; The binocular measurement module is used to acquire images of ultraviolet fluorescent targets and to track and identify the position of the target center. When the ultraviolet lamp is insufficient, it irradiates ultraviolet light onto the ultraviolet fluorescent target of the pantograph to make the fluorescent target emit light, which, together with the binocular measurement module, completes image acquisition. The industrial control computer is used to process the images acquired by the binocular measurement module. When the average pixel value of the target point is lower than the threshold, it controls the ultraviolet lamp to be turned on.

4. The anti-sunlight non-contact pantograph movement status monitoring device according to claim 3, characterized in that, The target point is characterized by a circular, triangular, polygonal, or cross-shaped shape.

5. The anti-sunlight non-contact pantograph movement status monitoring device according to claim 3, characterized in that, The target point is located at the ram's horn or at 1 / 4 or 3 / 4 of the center of the pantograph.

6. The anti-sunlight non-contact pantograph movement status monitoring device according to claim 3, characterized in that, The binocular measurement module consists of two industrial cameras.

7. The anti-sunlight non-contact pantograph movement status monitoring device according to claim 3, characterized in that, The binocular measurement module uses a tracking algorithm to track, identify, and measure the position of the target center.

8. The anti-sunlight non-contact pantograph movement status monitoring device according to claim 3, characterized in that... The binocular measurement module uses the pixel centroid method to acquire images of ultraviolet fluorescent targets.

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