Railway Train Image Acquisition Method Based on Trackside Image Data Acquisition Card

Abstract

This invention discloses a railway train image acquisition method based on a trackside image data acquisition card, belonging to the field of locomotive wheel signal processing technology. The invention addresses the problem of asynchronous wheel sensor signals received by existing data acquisition cards, resulting in multiple axle data points or missing axle data. It includes using a programmable logic chip to acquire the sensor signals from the wheel sensors, while simultaneously recording the time point of each sensor signal using a timer within the programmable logic chip, forming a sensor signal time sequence for each locomotive; and controlling the trackside image data acquisition card to acquire images based on the sensor signal time sequence. By obtaining an accurate locomotive sensor signal time sequence and transmitting it to the trackside image data acquisition card, this invention enables the trackside image data acquisition card to obtain train image data at the corresponding time more accurately.

Description

Technical Field

[0001] This invention relates to a railway train image acquisition method based on a trackside image data acquisition card, belonging to the field of locomotive wheel signal processing technology. Background Technology

[0002] A data acquisition card (hereinafter referred to as a general acquisition card) has the ability to automatically acquire analog or digital signals from the device and send them to a host computer for analysis and processing, as well as control external devices through an interface. It is a computer expansion card that integrates data acquisition and control functions. Currently, general acquisition cards on the market are either expensive or their performance is limited by the interruption delay of the general system and the operation delay of the software, resulting in the acquired signals being out of sync with the actual signals. As a result, when used in image acquisition equipment in the railway industry, it often leads to image loss or image crosstalk.

[0003] Wheel sensors (referred to as magnets) disturb the surrounding magnetic field and generate signals when a wheel passes over or moves away from a permanent magnet. Each time a wheel travels across the railway track, the wheel sensor generates a corresponding waveform. After data acquisition and processing, the host computer displays the current vehicle information and controls the data acquisition card to acquire images. The latency issues inherent in general-purpose data acquisition cards can cause axle information to be delayed or overlapped with subsequent information. Furthermore, various external interferences, such as electromagnetic interference, vibration interference, and railway backflow interference, can generate interference signals and cause wheel sensors to malfunction, resulting in multiple axle data points or missing axle data, leading to incorrect judgments of the current locomotive information by the equipment.

[0004] The industrial cameras used in trackside image acquisition equipment primarily employ LVDS and RS-485 for data transmission. When using a general-purpose acquisition card for image acquisition, external equipment is required to perform voltage level matching between the two devices before camera control can be initiated. Existing matching devices are all single-channel matching devices, which is costly and increases the space occupied by the equipment when multiple cameras are mounted. Summary of the Invention

[0005] To address the issue that existing data acquisition cards receive wheel sensor signals that are out of sync with the actual signals, resulting in multiple or missing axle data, this invention provides a railway train image acquisition method based on a trackside image data acquisition card.

[0006] The present invention provides a railway train image acquisition method based on a trackside image data acquisition card, comprising:

[0007] The sensor signals from the wheel sensors are collected using a programmable logic chip. At the same time, the time point of each sensor signal is recorded by the timer inside the programmable logic chip, and the sensor signal time sequence of each locomotive is formed.

[0008] The image acquisition card is controlled to acquire images based on the time sequence of the sensor signals.

[0009] According to the railway train image acquisition method based on a trackside image data acquisition card of the present invention, the trackside image data acquisition card is configured with a locomotive information database. The trackside image data acquisition card compares the time sequence of the sensing signal with the data in the locomotive information database to determine the current locomotive model and corrects the time sequence of the sensing signal to correspond to the vehicle wheelbase.

[0010] According to the railway train image acquisition method based on a trackside image data acquisition card of the present invention, the data types in the locomotive information database include locomotive model and the wheelbase of the vehicle corresponding to the locomotive model.

[0011] According to the railway train image acquisition method based on a trackside image data acquisition card of the present invention, the correction of the sensor signal time sequence corresponding to the vehicle wheelbase includes:

[0012] If the sensor signal time sequence is compared with the corresponding vehicle wheelbase information and it is determined that there are multiple time points, then the multiple time points are filtered out.

[0013] If a time sequence of the sensor signal is compared with the corresponding vehicle wheelbase information and it is determined that there is a missing axle time point, then the missing axle time point is filled in.

[0014] According to the railway train image acquisition method based on a trackside image data acquisition card of the present invention, the trackside image data acquisition card is configured with a level matching module for achieving level matching with an industrial camera.

[0015] According to the railway train image acquisition method based on the trackside image data acquisition card of the present invention, the level matching module converts the single-channel output signal of the trackside image data acquisition card into multiple LVDS signals or multiple 485 signals for output.

[0016] According to the railway train image acquisition method based on the trackside image data acquisition card of the present invention, the multi-channel LVDS signal output terminal or the multi-channel 485 signal output terminal of the trackside image data acquisition card is respectively connected to an industrial camera.

[0017] According to the railway train image acquisition method based on the trackside image data acquisition card of the present invention, the timer is started when the programmable logic chip acquires the sensing signal of the first wheel sensor and is turned off after the locomotive leaves.

[0018] According to the railway train image acquisition method based on the trackside image data acquisition card of the present invention, the time sequence of the sensing signal of the programmable logic chip is acquired by the host computer and then transmitted to the trackside image data acquisition card, and the trackside image data acquisition card controls the corresponding industrial camera to perform image acquisition.

[0019] According to the railway train image acquisition method based on the trackside image data acquisition card of the present invention, the locomotive information database is updated in real time according to the locomotive model.

[0020] The beneficial effects of the present invention are as follows: The method of the present invention uses a timer to determine the time of signal generation, which can avoid interruption delay of the host computer system and operation delay of the software, and can avoid the occurrence of multi-axis or missing axis situations, providing a reliable time basis for accurately capturing locomotive images.

[0021] The method of this invention corrects the time sequence of the sensor signal by using a pre-set locomotive information database. Even if there are multiple axes or missing axes in the time sequence, it can automatically correct the multiple axes or missing axes information in the time sequence of the sensor signal, thereby ensuring the accuracy of the time sequence signal transmitted to the trackside image data acquisition card, and thus ensuring that the acquired locomotive images are accurate.

[0022] The method of this invention enables precise control of trackside industrial cameras, thereby achieving accurate image acquisition. Attached Figure Description

[0023] Figure 1 This is a comparison diagram of different states of wheel sensor signals in the railway train image acquisition method based on trackside image data acquisition card described in this invention;

[0024] Figure 2 This is a flowchart of the railway train image acquisition method based on a trackside image data acquisition card as described in this invention;

[0025] Figure 3 This is an example diagram of a specific module structure of a trackside image data acquisition card. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0029] Specific Implementation Method 1: Combination Figure 1 and Figure 2As shown, this invention provides a railway train image acquisition method based on a trackside image data acquisition card, including:

[0030] The sensor signals from the wheel sensors are collected using a programmable logic chip. At the same time, the time point of each sensor signal is recorded by the timer inside the programmable logic chip, and the sensor signal time sequence of each locomotive is formed.

[0031] The image acquisition card is controlled to acquire images based on the time sequence of the sensor signals.

[0032] This implementation method allows for precise data acquisition timing. It records the current moment of the wheel sensor's sensing signal by using a timer for calibration. This method of determining the moment is more direct and avoids the interruption and delay issues that exist in the method of acquiring sensing signals through host computer control. It also avoids software operation delays, thereby controlling the industrial camera to accurately capture images and obtain vehicle information.

[0033] Furthermore, combined with Figure 2 As shown, the trackside image data acquisition card is configured with a locomotive information database. The trackside image data acquisition card compares the time sequence of the sensing signal with the data in the locomotive information database to determine the current locomotive model and corrects the time sequence of the sensing signal to correspond to the vehicle wheelbase.

[0034] This implementation method can automatically align the data acquisition time and automatically correct the axle information.

[0035] As an example, the data types in the locomotive information database include locomotive models and the wheelbase of the vehicles corresponding to the locomotive models.

[0036] As an example, the correction of the sensor signal time series to the vehicle wheelbase includes:

[0037] The collected sensor signal time series is compared with the internal data of the locomotive information database. If the sensor signal time series is compared with the corresponding vehicle wheelbase information and it is determined that there are multiple axle time points, then the multiple axle time points are filtered out.

[0038] If a missing axle time point is determined by comparing the sensor signal time sequence with the corresponding vehicle wheelbase information, the missing axle time point is then filled in. This ensures that the received sensor signal time sequence is accurate, thereby accurately determining the locomotive model, and then further controlling the camera to acquire images to obtain locomotive information.

[0039] Combination Figure 1 As shown, existing general-purpose data acquisition cards directly perform output control after acquiring external signals. For Figure 1In a normal signal state, without any other processing measures, if affected by system host computer interrupt delays or software operation delays, the received signal may be shifted backwards, such as... Figure 1 The signal is delayed; in severe cases, it may even lead to signal loss, such as... Figure 1 This invention addresses the issue of data loss due to signal delay. The method utilizes a timer within a programmable logic chip to record the time points and sequence numbers of all externally acquired signals. These signals can then be read by a host computer, aligned one by one, and finally used to control image acquisition.

[0040] After each locomotive departs, a timer can be set to reset after 1 minute, and restart the timing when the first magnet signal is received again. This method does not involve a host computer, avoiding the effects of signal interruption delay and software operation delay. Image acquisition control based on the signal obtained in this implementation method will not result in image crosstalk or image loss, and it can also avoid delays caused by hardware conditions, such as clock errors.

[0041] Meanwhile, the operating conditions of railway vehicles are complex, with numerous external interferences such as electromagnetic interference, vibration interference, and railway backflow interference. These can all cause wheel sensors to erroneously trigger signals or interfere with and lose normal signals, resulting in inaccurate vehicle information. Under normal circumstances, after the acquisition card receives the first signal from the magnet, the time interval between each magnet signal is fixed and only affected by speed, exhibiting a proportional amplification phenomenon. This implementation method can correct the sensor signal time sequence based on the localized configuration of the locomotive information database, avoiding inaccurate vehicle information acquisition due to signal recording errors.

[0042] Furthermore, the trackside image data acquisition card integrates a level matching module to achieve level matching with the industrial camera.

[0043] As an example, the level matching module converts the single-channel output signal of the trackside image data acquisition card into multiple LVDS signals or multiple 485 signals for output.

[0044] In this embodiment, the multi-channel output of the trackside image data acquisition card can be connected to multiple industrial cameras. The multi-channel LVDS signal output terminal or the multi-channel 485 signal output terminal of the trackside image data acquisition card is connected to one industrial camera respectively.

[0045] In this embodiment, the timer starts when the programmable logic chip acquires the first wheel sensor sensing signal and shuts off after the locomotive leaves.

[0046] The control logic of the method of this invention is as follows: Figure 2As shown, when the programmable logic chip acquires the first external magnet signal, the timer starts and records the accurate time point and sequence number of each signal generated by the magnet through the internal timer. The current signal sequence number and time point can be read by the host computer and compared and corrected with the local configuration of the trackside image data acquisition card. Finally, the control signal is output to control the acquisition of multiple images and obtain vehicle-related information based on the acquired images.

[0047] Furthermore, the time sequence of the sensing signals from the programmable logic chip is acquired by the host computer and transmitted to the trackside image data acquisition card, which then controls the corresponding industrial camera to acquire images.

[0048] Furthermore, the locomotive information database is updated in real time based on locomotive models. It stores information on all locomotives currently operating on railways and allows for the addition of new models. It also enables local configuration of locomotive information based on the specific conditions of different railway sections.

[0049] The internal structure of the trackside image data acquisition card in this embodiment can be as follows: Figure 3 As shown, it mainly includes a main control module, power supply module, communication module, peripheral module, acquisition module, and level matching module. The main control module is primarily responsible for controlling each module; the power supply module ensures normal operation and powers each chip; the communication module transmits acquired data and commands; the acquisition module acquires the time sequence of sensor signals; and the level matching module converts the single-channel output of the trackside image data acquisition card to multi-channel output. Multiple output channels can simultaneously connect to multiple cameras, ensuring that the number of output channels can be freely configured when used on different devices, thus saving equipment costs and reducing the space occupied by the equipment.

[0050] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A method for acquiring railway train images based on a trackside image data acquisition card, characterized in that... include, The sensor signals from the wheel sensors are collected using a programmable logic chip. At the same time, the time point and corresponding sequence number of each sensor signal are recorded by the timer inside the programmable logic chip, and the sensor signal time sequence of each locomotive is formed. The image acquisition card on the trackside is controlled to acquire images based on the time sequence of the sensor signals. The trackside image data acquisition card is configured with a locomotive information database. The trackside image data acquisition card compares the time sequence of the sensing signal with the data in the locomotive information database to determine the current locomotive model and corrects the time sequence of the sensing signal to correspond to the vehicle wheelbase. The data types in the locomotive information database include locomotive models and the wheelbase of the vehicles corresponding to the locomotive models; The correction of the sensor signal time sequence to correspond to the vehicle wheelbase includes: if the sensor signal time sequence is compared with the corresponding vehicle wheelbase information and it is determined that there are multiple axle time points, then the multiple axle time points are filtered out; if the sensor signal time sequence is compared with the corresponding vehicle wheelbase information and it is determined that there are missing axle time points, then the missing axle time points are filled in. The trackside image data acquisition card is equipped with a level matching module to achieve level matching with the industrial camera; The level matching module converts the single-channel output signal of the trackside image data acquisition card into multiple LVDS signals or multiple 485 signals for output; Each of the multiple LVDS signal outputs or multiple 485 signal outputs of the trackside image data acquisition card is connected to an industrial camera. The timer starts when the programmable logic chip acquires the first wheel sensor signal and shuts off after the locomotive leaves.

2. The railway train image acquisition method based on a trackside image data acquisition card according to claim 1, characterized in that, The time sequence of the sensing signals from the programmable logic chip is acquired by the host computer and then transmitted to the trackside image data acquisition card. The trackside image data acquisition card controls the corresponding industrial camera to acquire images.

3. The railway train image acquisition method based on a trackside image data acquisition card according to claim 1, characterized in that, The locomotive information database is updated in real time according to the locomotive model.

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