CN104330031A - Portable overhead line geometric parameters detection method and system based on binocular linear array CCD camera - Google Patents

Abstract

The invention discloses a portable overhead line geometric parameters detection method and a portable overhead line geometric parameters detection system based on a binocular linear array CCD camera. The method includes the steps of: 1, disposing two imaging devices on two tracks, disposing a line light source at the center between the two imaging devices; 2, transmitting linear illuminating light towards the overhead line, wherein generated reflected light respectively enter the two imaging devices for imaging; 3, calculating the geometric parameters of the overhead line. The system is used for implementing the above method. The portable overhead line geometric parameters detection system has the advantages of being simple in structure, convenient to operate and carry and capable of working all the time.

Description

A portable catenary geometric parameter detection method and system based on a binocular linear array CCD camera

technical field

The invention mainly relates to a railway catenary detection system, in particular to a portable catenary geometric parameter detection method and system based on a binocular linear array CCD camera.

Background technique

At present, when testing railway catenary, the measurement of conventional geometric parameters such as catenary height, pull-out value, and side limit is mostly carried out by manual fixed-point measurement. This method of manual fixed-point measurement generally has shortcomings such as discontinuous measurement values and low measurement efficiency. Therefore, in the face of today's increasingly high safety requirements for electrified railways, the traditional manual fixed-point detection technology has large detection errors, discontinuous detection waveforms, and low efficiency. Imported components, the overall cost of the system is expensive; therefore, there is an urgent need for a fast, continuous, energy-saving, and cost-effective catenary geometric parameter detection system.

Contents of the invention

The technical problem to be solved by the present invention is: aiming at the technical problems existing in the prior art, the present invention provides a portable catenary geometric parameter based on a binocular linear array CCD camera that is simple in structure, easy to operate, easy to carry, and can work around the clock Detection method and system.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A portable catenary geometric parameter detection method based on a binocular linear array CCD camera, the steps are:

(1) two imaging devices are arranged on two rails, and the line light source used to generate illumination light is arranged at the center between the two imaging devices;

(2) emit illumination light toward the contact line, and the generated reflected light respectively enters into two imaging devices for imaging;

(3) The corresponding catenary geometric parameters are obtained by the following formula:

$\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

$\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

Among them, H is the guide height, a is the pull-out value, the distance between the centers of the two imaging devices is S, h0 is the height from the rail plane to the imaging plane, and the reflected light of the contact line to the illumination light is imaged on the two imaging devices , and the included angles with the imaging plane after coordinate transformation are θ1 and θ2 respectively.

The present invention further provides a portable catenary geometric parameter detection system based on a binocular linear array CCD camera, including a portable car and two cameras installed on the portable car, a CCD camera information collection and processing embedded system, and a line light source. The line light source is installed in the middle of the two cameras, and the linear light emitted by the line light source is reflected by the measured contact line and then enters the camera and is imaged in the line array CCD.

As a further improvement of the present invention: a filter is placed above the line array CCD of the camera.

As a further improvement of the present invention: a cylindrical mirror is installed between the filter mirror and the line array CCD.

As a further improvement of the present invention: the generatrix of the cylindrical mirror is perpendicular to the line array CCD, one side of the plane of the cylindrical mirror is parallel to the camera installation plane, and the convex surface of the cylindrical mirror faces towards the catenary.

As a further improvement of the present invention: the portable trolley includes a chassis, and the chassis is provided with a camera installation plane parallel to the rail plane.

As a further improvement of the present invention: the wheels of the chassis are located above the track and can walk along the track, the chassis is also provided with auxiliary wheels, the auxiliary wheels are used to cooperate with the inner surface of the track, and the vehicle is driven by springs The body is close to the orbit.

As a further improvement of the present invention: a speed measuring encoder is provided at the wheel to detect the real-time speed of the wheel.

As a further improvement of the present invention: the CCD camera information acquisition and processing embedded system includes:

FPGA-based CCD drive module, when the reflected light 16 is imaged on the CCD photosensitive unit through the optical system, the CCD drive circuit drives the CCD with pulses of a certain frequency to output signals reflecting object displacement information;

The signal amplification sampling module is used to amplify the pulse modulation signal output by the CCD, and then use the sampling circuit to sample the continuous video signal at intervals in time, and turn the CCD video signal into a discrete analog signal;

High-speed A/D conversion and high-speed cache module, the analog signal sampled by the signal amplification sampling module is converted into a digital value after high-speed A/D conversion, and then processed by the microcontroller after being cached.

As a further improvement of the present invention: the portable car is provided with a touch screen display of an industrial PC.

Compared with the prior art, the present invention has the advantages of:

1. A portable catenary geometric parameter detection method and system based on a binocular linear array CCD camera of the present invention has simple structure, easy operation, easy portability, small amount of stored data, and small amount of calculation. The components used are stable and reliable, and have a long life. Ability to draw geometric parameter waveforms in real time.

2. A portable catenary geometric parameter detection method and system based on a binocular linear array CCD camera of the present invention adopts a lighting line light source, can work around the clock, has low energy consumption, and has little environmental pollution.

Description of drawings

Fig. 1 is a schematic diagram of the principle of the method of the present invention.

Fig. 2 is a schematic diagram of the principle of calculating the conductance and pull-out value of the contact wire in the method of the present invention.

Fig. 3 is a schematic diagram of the principle of graphical data display in a specific application example of the present invention.

Fig. 4 is a schematic diagram of the structure and principle of the detection system of the present invention in a specific application example.

Fig. 5 is a schematic diagram of the frame composition of the detection system of the present invention in a specific application example.

6 is a schematic diagram of the composition of the CCD camera information collection and processing embedded system in a specific application example of the detection system of the present invention.

illustration:

1. Camera; 2. Camera installation plane; 3. Line light source; 4. Touch screen display of industrial PC; 5. Handle; 6. Wheel; 7. Speed encoder; 8. Rail plane; 9. Chassis; 10. Push Rod; 11, track; 12, spring; 13, auxiliary wheel; 14, roadbed; 15, illumination light; 16, reflected light; 17, filter mirror; 18, cylindrical mirror; 19, contact line.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

A kind of portable catenary geometric parameter detection method based on binocular linear array CCD camera head of the present invention, its steps are:

(1) two imaging devices are arranged on two rails 11, and the line light source 3 used to generate linear illumination light is arranged at the center between the two imaging devices;

(2) emit illumination light toward the contact line 19, and the generated reflected light 16 respectively enters into two imaging devices for imaging;

(3) The corresponding catenary geometric parameters are obtained by the following formula (combining Figure 1 and Figure 2):

$\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

$\mathrm{<span\; class="notranslate">\; a</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; S</span>}\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}$

Among them, H is the guide height, a is the pull-out value, the distance between the centers of the two imaging devices is S, h0 is the height from the rail plane 8 to the imaging plane, and the reflected light 16 of the contact line 19 to the illumination light is formed in the two imaging devices. The image is formed on the linear array CCD photosensitive element of the device, and the included angles with the imaging plane after coordinate transformation are θ1 and θ2 respectively. Fig. 3 is a schematic diagram showing graphical data of the present invention in a specific application example,

As shown in Fig. 4, Fig. 5 and Fig. 6, a kind of portable catenary geometric parameter detection system based on binocular linear array CCD camera of the present invention comprises portable dolly and two cameras 1, CCD camera that are installed on the portable dolly In the embedded system for information collection and processing, the line light source 3 is installed in the middle of the two cameras 1 . Both cameras 1 are binocular line array CCD cameras, i.e. charge-coupled device line array CCD cameras. On both sides of the vertical bisector between the rails 11 , the line array CCD is parallel to the installation surface, and a certain installation distance is maintained between the two cameras 1 .

In this embodiment, a filter 17 is further placed above the line array CCDs of the two cameras 1, mainly for filtering out part of sunlight, line lights and part of light pollution. A semi-cylindrical cylindrical lens 18 with a certain geometric dimension is installed between the optical filter 17 and the line array CCD, and the cylindrical lens 18 can image the incident light as a straight line (ideally), and this straight line and the line array The sensors of the CCD intersect at one point. Therefore, using the cylindrical mirror 18 can conveniently realize the measurement of the angle. In addition, the generatrix of the cylindrical mirror 18 is perpendicular to the line array CCD, the plane side of the cylindrical mirror 18 is parallel to the camera installation plane 2, and the convex surface of the cylindrical mirror 18 faces the direction of the catenary.

In this embodiment, the linear light source 3 adopts a linear light source with a certain length, which is installed in the middle of the two cameras 1 so that the distance from each camera 1 is equal. The illumination light emitted by the line light source 3 is reflected by the measured contact line and then enters the camera 1 and is imaged in the line array CCD.

The portable trolley is used as the carrier of equipment such as the camera 1, which improves the convenience and portability of loading and unloading. The portable trolley includes a chassis 9, a handle 5 and a push rod 10, and the chassis 9 provides a camera installation plane 2 parallel to the rail plane 8 for the camera 1. The wheels 6 of the chassis 9 are located above the track 11 and can walk along the track 11. The track 11 is installed on the roadbed 14, and the handle 5 and the push rod 10 are used to control the walking of the chassis 9. Speed measuring encoder 7 is installed near the wheel 6 of chassis 9, and is used for detecting the real-time speed of wheel 6. In this embodiment, an auxiliary wheel 13 is provided on the chassis 9, and the auxiliary wheel 13 is used to cooperate with the inner surface of the track 11, and the vehicle body is brought close to the track 11 through the spring 12. The portable trolley is further provided with a touch screen display 4 of an industrial control PC, through which the construction personnel can operate the set of equipment, and the touch screen display 4 of the industrial control PC can also display data such as contact wire lead height and pull-out value in real time. The portable trolley of the present invention is light and simple in design, and railway construction personnel can rely on individuals to set up the trolley on the track 11, rely on manual promotion or use a simple power system as an alternative to move on the track 11. The whole portable dolly is pressed against one side of the track 11 by the auxiliary wheels 13 and the spring 12, so that the camera installation plane 2 above the dolly is always kept parallel to the rail plane 8. In addition, by using the photoelectric speed measuring encoder 7, the displacement data of the trolley can be collected in real time.

Referring to Fig. 1, the line light source 3 irradiates the illumination light 15 on the contact line, and the reflected light 16 is finally projected on the linear array CCD photosensitive element of the camera 1 through the filter mirror 17 and the cylindrical mirror 18, and the reflected light 16 is on the CCD. The imaging position is processed by the conversion of imaging coordinates and space coordinates, geometric parameter calculation, etc., and finally obtains the conduction height and pull-out value of the contact line.

As shown in Figure 1 and Figure 2, the analog voltage output by the linear array CCD sensor is related to the incident light intensity and the frame transfer frequency, and increases with the increase of the incident light intensity, and decreases with the increase of the frame transfer frequency . When the incident light is stronger, or the frame transfer pulse frequency is smaller, that is, the integration time is longer, the corresponding photosensitive unit captures more light. The present invention adopts the FPGA-based CCD drive circuit design, so that the CCD outputs an analog voltage, and the discrete analog voltage obtained after sampling is sent to a high-speed A/D conversion module to form a digital value, and then matches the speed of the processor through the cache, Finally processed in the processor. The processor is also able to adjust the CCD drive circuit based on the CCD output feedback.

In this embodiment, the CCD camera information acquisition and processing embedded system includes the following parts:

FPGA-based CCD drive module, when the laser reflected light is imaged on the CCD photosensitive unit through the optical system, the CCD drive circuit drives the CCD with a pulse of a certain frequency to output a signal reflecting the displacement information of the object. The driving methods often used in the prior art include direct digital driving method, EPROM driving method and single-chip microcomputer driving method. Defects with more waste and less frequency. The present invention adopts the FPGA to design the CCD drive circuit to solve the above problems well, and can provide high-frequency acquisition speed.

Signal amplification sampling module, this module first amplifies the pulse modulation signal output by CCD, and then uses the sampling circuit to sample the continuous video signal at intervals in time, and converts the CCD video signal into a discrete analog signal.

High-speed A/D conversion and high-speed cache module, the analog signal sampled by the signal amplification sampling module is converted into a digital value after high-speed A/D conversion, and then processed by the microcontroller after being cached.

The present invention further includes a computer monitoring and processing device, which is used to calculate the photosensitive information of the camera 1 of the two linear array CCDs transmitted by the CCD camera information collection and processing embedded system through triangles, etc. to obtain the lead height and pull-out value of the contact line , and display it in real time on the touch screen display 4 of the industrial PC in the form of graphics.

The present invention further includes a set of special data processing software, which is installed on the computer monitoring and processing equipment, which uses the upper and lower computer communication technology, CCD camera synchronous drive technology, camera calibration technology, triangulation measurement technology, camera coordinates and Space coordinate transformation and other technologies enable the whole system to coordinate well.

The above are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims (10)

1., based on a portable contact net geometric parameter detection method for binocular line array CCD camera, it is characterized in that, step is:

(1) two imaging devices are arranged on two tracks (11), are used for producing the line source (3) of illumination light and are arranged in center between two imaging devices;

(2) launch wire illumination light towards osculatory (19), the reflected light produced (16) enters into respectively in two imaging devices and carries out imaging;

(3) corresponding contact net geometric parameter is obtained by following formula:

$H=h0+\frac{S\tan \mathrm{\&theta;}1\tan \mathrm{\&theta;}2}{\tan \mathrm{\&theta;}1+\tan \mathrm{\&theta;}2}$

$a=\frac{S}{2}-\frac{S\tan \mathrm{\&theta;}1}{\tan \mathrm{\&theta;}1+\tan \mathrm{\&theta;}2}$

Wherein, H for leading height, a is stagger, distance between two imaging device centers is S, h0 is the height of rail plane (8) to imaging plane, osculatory (19), to reflected light (16) imaging on two imaging devices of line source, distinguishes θ 1, θ 2 with the angle of imaging plane after coordinate conversion.

2. the portable contact net geometric parameter detection system based on binocular line array CCD camera, it is characterized in that, comprise portable buggy and be installed on two cameras (1) on portable buggy, CCD camera information acquisition process embedded system, line source (3), described line source (3) is installed on the middle of two cameras (1), the illumination light that described line source (3) sends by survey after osculatory (19) reflects and enter camera (1) and imaging in line array CCD.

3. the portable contact net geometric parameter detection system based on binocular line array CCD camera according to claim 2, is characterized in that, lay optical filtering (17) above the linear array CCD of described camera (1).

4. the portable contact net geometric parameter detection system based on binocular line array CCD camera according to claim 3, is characterized in that, install cylindrical mirror (18) between described optical filtering (17) and linear array CCD.

5. the portable contact net geometric parameter detection system based on binocular line array CCD camera according to claim 4, it is characterized in that, the bus of described cylindrical mirror (18) is vertical with linear array CCD, the parallel camera mounting plane (2) in plane side of described cylindrical mirror (18), described cylindrical mirror (18) convex surface facing contact net direction.

6. according to the portable contact net geometric parameter detection system based on binocular line array CCD camera in claim 2 ~ 5 described in any one, it is characterized in that, described portable buggy comprises chassis (9), and described chassis (9) are provided with the camera mounting plane (2) being parallel to rail plane (8).

7. the portable contact net geometric parameter detection system based on binocular line array CCD camera according to claim 6, it is characterized in that, the wheel (6) on described chassis (9) is positioned at the top of track (11) and can walks along track (11), described chassis (9) is also provided with auxiliary wheel (13), described auxiliary wheel (13) is used for coordinating with the medial surface of track (11), and makes car body near track (11) by spring (12).

8. the portable contact net geometric parameter detection system based on binocular line array CCD camera according to claim 7, it is characterized in that, described wheel (6) place is provided with speed measuring coder (7), be used for detect wheel (6) real-time speed.

9. according to the portable contact net geometric parameter detection system based on binocular line array CCD camera in claim 2 ~ 5 described in any one, it is characterized in that, described CCD camera information acquisition process embedded system comprises:

Based on the CCD driver module of FPGA, when reflected light (16) through optical system imaging on CCD photosensitive unit, CCD driving circuit exports the signal of reflection displacement body information with the pulsed drive CCD of certain frequency;

Signal amplifies sampling module, and the pulse-modulated signal being used for CCD to export after amplifying, then carries out interval sampling with sample circuit to continuous print vision signal in time, and CCD vision signal is become discrete simulating signal;

High-speed a/d conversion and cache module, the numerical value that the simulating signal after the sampling of signal amplification sampling module becomes numeral after high-speed a/d conversion transfers to microcontroller to process again after high-speed cache.

10., according to the portable contact net geometric parameter detection system based on binocular line array CCD camera in claim 2 ~ 5 described in any one, it is characterized in that, described portable buggy is provided with the touch-screen display (4) of industry control PC.