CN210136188U

CN210136188U - Equal-intensity light source video detection device for apparent damage of external steel cable

Info

Publication number: CN210136188U
Application number: CN201920905060.6U
Authority: CN
Inventors: 周子杰; 吴华勇; 赵荣欣
Original assignee: Shanghai Building Science Research Institute Co Ltd
Current assignee: Shanghai Building Science Research Institute Co Ltd
Priority date: 2019-06-17
Filing date: 2019-06-17
Publication date: 2020-03-10
Anticipated expiration: 2029-06-17

Abstract

The utility model relates to an external cable wire apparent damage's equal strong light source video detection device, through shading overcoat shielding external light source, make the cable wire that awaits measuring survey the regional interior no external light source, simultaneously, set up built-in light source in the shading overcoat to make the illumination of built-in light source to cable surface detection area's intensity unified, then the background light information of final photographic image can keep unanimous, including the image intensity of same cable wire axial position detection area under the different camera recordings and the image intensity of same camera in the different longitudinal position of cable wire all keep unanimous. The utility model discloses an isolated external light of shielding sheath forms the airtight environment of light at the detection area for external light environment falls to minimumly to the influence of video detection data.

Description

Equal-intensity light source video detection device for apparent damage of external steel cable

Technical Field

The utility model relates to an apparent inspection field of external cable wire, concretely relates to control detection light source is in order to improve video image detection quality device.

Background

The detection of the cable body is one of maintenance work of an operated cable structure, and the method for detecting the surface of the cable body by adopting video is already applied to actual engineering. However, practical application results show that, for the detection of the external cable body, the video image is very sensitive to external light, so that the detection result is seriously influenced. For example, the corresponding sunshine light intensity on the same cross-section of the cable body is different, the sunshine light intensity corresponding to the same camera at different moments is also different, and the imaging quality is also seriously influenced by the problems of possible local reflection of light of the external environment and the like during detection. At present, a large number of video signals are automatically processed through a computer algorithm, and the accuracy of an analysis result is greatly improved under the unified scene light condition.

Chinese patent (CN 201110285061) proposes a detection method that a plurality of fixed cameras are installed through a cable climbing mechanism, the cameras collect images on the surface of a cable in real time around the circumference of the cross section of the cable when the cable climbing mechanism crawls along the axial direction of the cable, and a plurality of camera images at the same moment are integrated to obtain the circumference of one section of the cable.

Chinese utility model patent (CN 204855400U) proposes through the serial mechanism and sensor in its claim, realizes location and the camera in the suspension cable crawls and the rotation of encircleing along the outer circumference of cable cross section, can realize the function of the all-round image information on gathering cable cross section circumference of a camera, needs the problem of using two at least to three cameras when adopting fixed camera to detect the suspension cable cross section in the solution traditional video detection.

Chinese utility model patent (CN 103698336B) is directed against the cable anchor district tradition and is carried out the weak point that detects the method through industrial endoscope, has proposed through constructional device such as reflector, with the narrow and small anchor region of external light source parallel guidance entering far away from the light source to gather the light signal that is transmitted back by the reflector through outside high definition telephoto objective and realize the remote detection to the inside cable of anchor district.

In addition, to the device of crawling that suspension cable detected and control system thereof, chinese utility model patent (CN 20495959598U), chinese utility model patent (CN 103194967 a), chinese utility model patent (CN 103552073B) and chinese utility model patent (CN 103696365B) all made the right application to the concrete structure of the equipment of crawling that the cable structure detected or the data connection mode between the devices.

The search results of the published patent show that in the patent related to the visual detection of a steel cable (including a stay cable and similar elongated structures made of steel material) based on video, no measures for dealing with the influence of an external light source on a video image and a related structural device are found, mainly in the claims of the design of a climbing device mechanism, a data transmission method and the like.

Disclosure of Invention

The utility model relates to a through shielding external light source, in the inside method and the device of establishing the uniform intensity light source of system certainly, realize the processing to the external light source influence of video image among the cable wire appearance detection.

In order to achieve the above object, an equal-intensity light source video detection device for apparent damage of an external steel cable is designed, which is characterized by comprising:

the shading sheath is annularly sleeved outside the steel cable stay;

the camera is arranged in the shading sheath, closely arranged in one-to-one correspondence with the built-in light source and aligned to the area to be measured of the steel cable to be measured;

the built-in light source is arranged in the shading sheath, closely arranged corresponding to the camera one by one and aligned to the area to be measured of the steel cable to be measured;

the cameras and the built-in light sources are symmetrically arranged along the cross section of the steel cable body along the center of a circle, the vertical distances from the cameras to the surface of the steel cable body are the same, and the vertical distances from the built-in light sources to the surface of the steel cable body are the same.

In order to realize the intensity control of the picture background light source, the adopted method is as follows: the shading outer sleeve shields an external light source, so that no external light source exists in the area to be measured of the steel cable, meanwhile, the built-in light source is arranged in the shading outer sleeve, the intensity of the built-in light source irradiating the surface detection area of the stay cable is uniform, the background light information of the final photographic image can be kept consistent, and the image intensity of the detection area at the axial position of the same steel cable and the image intensity of the same camera at different longitudinal positions of the steel cable, which are recorded by different cameras, are kept consistent.

In order to realize the consistent light intensity of the built-in cameras, the adopted method comprises the following steps: in the arrangement scheme of the fixed cameras, the detection areas are irradiated by the multiple built-in light sources through selecting proper built-in light source irradiation ranges in the circumference of the cross section of the inhaul cable, the irradiation areas are not mutually overlapped or slightly intersected, and the illumination intensity of the detection areas can be approximately equal through arranging the cameras and the light sources at different positions at the same height on the surface of the inhaul cable.

The concrete principle is, light source through waiting illumination intensity is according to the utility model discloses a light source arrangement mode etc. highly arrange around circular cross section steel bundle outward for illumination region does not overlap each other through the luminous angle of adjustment light source, then the illumination distance of light source to steel bundle surface each point in each light source irradiation range approximately equals, and along with the increase of light source arrangement quantity, this kind of approximate equals gradually and approaches to completely equal. Under the condition that the illumination distance and the illumination intensity of the light source are the same, the illumination illuminance obtained on the surface of the steel beam is the same at each point, so that the aim of equal illumination illuminance is fulfilled. Therefore, the interference of background light and shadow noise can be greatly reduced by the shot picture or video, and the detection and analysis precision is improved.

According to the realization principle, the illumination intensity of the steel beam surface with approximate equal intensity can be obtained by adjusting the number and the arrangement of the light sources so as to meet the illumination requirements of various detection photography.

For the scheme that a single camera rotates around the section of the steel cable, only the steel cable rotating ring is basically overlapped with the centroid of the steel cable, in the shooting process, the intensity of background light formed by each point is the same when the built-in light source shoots on the circumference of the section, the corresponding shooting range is the same, and finally the formed video image has a background with approximately equal intensity.

Thus, the resulting lighting conditions may be approximately considered substantially similar within the detection range. The existing automatic video analysis method has strong robustness to the tiny background difference, and can obtain a good analysis result.

The methods of power supply, video signal transmission, data processing and damage assessment analysis of the device are not within the scope of this patent application, and the scope of this patent application is not for a crawling device that drives the movement of the device on a wire rope.

Compared with the traditional cable video detection technology, the utility model has the advantages of:

(1) external light is isolated through the shielding sheath, and an optical closed environment is formed in the detection area, so that the influence of the external light environment on video detection data is reduced to the minimum;

(2) through the matching use of the camera and the built-in light source, the light background intensity in the closed detection area of the steel cable is approximately the same, the quality of the obtained detected video image data is improved, the approximately same image background light source can reduce the dependency on a background signal recognition algorithm in the later data analysis process, the analysis algorithm is greatly simplified, and the analysis speed and the quality of an evaluation result are improved;

(3) owing to shielded external light source's influence, adopted the utility model discloses a cable wire detects the suitability that can expand under the different environmental condition, also can realize the night work that the cable body detected.

Drawings

Fig. 1 is a schematic view of the overall appearance of the device installed on the cable according to the embodiment of the present invention.

Fig. 2 is a schematic view of the internal structure of the device along the longitudinal direction of the inhaul cable in the embodiment of the present invention.

Fig. 3 is the embodiment of the present invention, wherein the octagonal outer shading sheath and the four cameras are schematically arranged.

Fig. 4 is the embodiment of the present invention, wherein the circular outer shading sheath and the three cameras are schematically arranged.

The notation in the figure is:

1-steel cable, 2-shading sheath, 3-camera, 4-built-in light source, 5-elastic support, 6-pulley, 7-flexible light barrier.

Detailed Description

The technical solution of the present invention will be further described with reference to the accompanying drawings and examples, which are believed to be clear to those skilled in the art.

Referring to fig. 1, an embodiment of the present invention provides a method and an apparatus for shielding an external light source and achieving a video detection of an approximately uniform background light signal through a built-in light source. Wherein, the device is wholly sleeved outside the cable body of the steel cable 1 and can be externally connected with a cable crawling robot to move.

The longitudinal constructional arrangement within the device is seen in fig. 2, wherein the shading sheath 2 forms an integral enclosure for the stay cable in the circumferential direction and at both ends of the cross-section. In order to adapt to structures with different cable body diameters, external spiral lines of the cable body and the like, the inner diameter of the sheath is larger than the outer diameter of the cable body, a gap between the shading sheath 2 and the cable body 1 is shielded by arranging the flexible light blocking sheet 7 between the shading sheath 2 and the outer wall of the cable body 1, and finally the overall shielding effect on an external light source is achieved.

In order to realize the axial movement of the device along the cable body under the devices such as the cable climbing robot, the two sides of the shading sheath 2 are provided with the embedded pulley device 6 in fig. 2, and the pulley 6 is fixedly connected with the shading sheath 2 through the elastic supporting 5. The elastic support 5 has certain rigidity, can adapt to climbing of guys with different diameters and overcome the obstruction of guy surface structures in the climbing process.

With reference to fig. 2 and 3, a pair of cameras 3 and a built-in light source 4 are closely arranged in the shading sheath 2, and a plurality of pairs of cameras 3 and built-in light sources 4 are symmetrically arranged along the center of the circle along the cross section of the cable body. Therefore, the vertical distances of the cameras 3 to the cable body surface are the same, and the vertical distances of the built-in light sources 4 to the cable body surface are the same.

The utility model discloses in, according to the detection needs, camera and built-in light source quantity and position can be adjusted, refer to fig. 3 and fig. 4. As long as arrange the principle with the utility model unanimously, then the quantity of difference and arrange all can realize under the form that video signal's the equal background signal intensity.

The present patent application is not limited to the above embodiments, and any person can make several local adjustments and improvements without departing from the patent principles of the present invention, and the present invention is considered to be within the protection scope of the present invention. Those not described in detail in this specification are within the skill of the art.

Claims

1. An external cable wire apparent damage equal-intensity light source video detection device is characterized by comprising:

the shading sheath is annularly sleeved outside the steel cable stay;

2. The device for detecting apparent damage of the constant-intensity light source of claim 1, wherein the cross section of the light-shielding sheath is concave, the light-shielding sheath forms an integral enclosure for the cable along the circumferential direction and two ends of the cross section, and the inner diameter of the sheath is larger than the outer diameter of the cable body.

3. The video detection device with the constant-intensity light source for the apparent damage of the external steel cable as claimed in claim 1 or 2, wherein the shielding of the gap between the light-shielding sheath (2) and the cable body of the steel cable (1) is realized by arranging a flexible light-blocking sheet (7) between the light-shielding sheath (2) and the outer wall of the cable body of the steel cable (1).

4. The equal-intensity light source video detection device for apparent damage of the external steel cable as claimed in claim 1 or 2, wherein the side end of the shading sheath (2) contacting with the steel cable is provided with an embedded pulley (6) through an elastic support (5), and the pulley (6) is fixedly connected with the shading sheath (2) through the elastic support (5).