CN211042730U

CN211042730U - Bridge displacement monitoring system based on visual perception

Info

Publication number: CN211042730U
Application number: CN201921621318.6U
Authority: CN
Inventors: 陈宇轩; 赵文一; 何显银; 宋杰; 董梅; 胡辉
Original assignee: Hangzhou Ruhr Technology Co Ltd
Current assignee: Hangzhou Ruhr Technology Co Ltd
Priority date: 2019-09-26
Filing date: 2019-09-26
Publication date: 2020-07-17
Anticipated expiration: 2029-09-26

Abstract

The embodiment of the utility model discloses bridge displacement monitoring system based on vision perception, this system includes: the target is arranged on the bridge; a vision sensor comprising a camera and a lens for capturing a target image of the target; and the image processing module is in communication connection with the visual sensor and is used for processing the target image and calculating the bridge displacement. The utility model discloses technical scheme carries out the monitoring of bridge displacement through the mode of target image is gathered to the vision sensor, has realized the automatic monitoring of bridge displacement, and system installation and operation are simple and easy, and bridge displacement monitoring precision is high.

Description

Bridge displacement monitoring system based on visual perception

Technical Field

The embodiment of the utility model provides a bridge detects technical field, especially relates to a bridge displacement monitoring system based on visual perception.

Background

With the increasing development of traffic, bridges have become important components of traffic infrastructure, and health monitoring of bridges has become increasingly important. The bridge deflection or bridge displacement can directly reflect the health condition of the bridge and is also an important parameter for representing the rigidity and the load capacity of the bridge structure.

At present, methods for measuring displacement of highway bridges are mainly divided into two types: one is to measure by using contact detection equipment such as a displacement meter, a static level gauge and the like; and the other is non-contact measurement based on technologies such as a total station, a GPS, a laser image method and the like. The contact detection method can have certain influence on the bridge, and is easily influenced by the field environment. While non-contact measuring means such as a total station, a GPS, a laser displacement meter, etc. can avoid damage to the structure, such devices are often greatly affected by the environment, and have high cost and limited accuracy.

SUMMERY OF THE UTILITY MODEL

The utility model provides a bridge displacement monitoring system based on vision perception to realize the monitoring of bridge displacement, be applicable to complicated scene simultaneously, extensive applicability, stability are good, the recognition accuracy is high.

The embodiment of the utility model provides a bridge displacement monitoring system based on vision perception, this bridge displacement monitoring system, include:

the target is arranged on the bridge;

a vision sensor comprising a camera and a lens for capturing a target image of the target;

and the image processing module is in communication connection with the visual sensor and is used for processing the target image and calculating the bridge displacement.

Optionally, the target is a two-dimensional code target.

Optionally, an aluminum alloy shell is arranged on the periphery of the vision sensor, wherein the surface of the aluminum alloy shell is coated with an anti-corrosion protective paint.

Optionally, the lens includes a telephoto lens or a binocular lens.

Optionally, work as the camera lens is long focus monocular head, the system still includes inclinometer and inclinometer are dull and stereotyped, inclinometer, camera and camera lens set up in on the inclinometer is dull and stereotyped, just the inclinometer with the camera is in same horizontal plane.

Optionally, the system further includes: and the lighting device is a light emitting diode array and is arranged at the periphery or the back of the target, or the lighting device is an infrared light source and is arranged on the lens.

Optionally, the system further includes: a tripod or a tall pole, the vision sensor being located above the tripod or the tall pole.

Optionally, the system further includes: and the power supply module is electrically connected with the visual sensor and the image processing module and comprises a voltage conversion interface for supplying power to the visual sensor and the image processing module.

Optionally, the image processing module is a notebook computer or a remote server.

Optionally, the camera further includes a GigE interface or a USB3.0 interface, configured to transmit the target image to the image processing module.

The utility model discloses technical scheme carries out the monitoring of bridge displacement through the mode of target image is gathered to the vision sensor, has realized the automatic monitoring of bridge displacement, and system installation and operation are simple and easy, and bridge displacement monitoring precision is high.

Drawings

Fig. 1 is a schematic view of a bridge displacement monitoring system based on visual perception provided by an embodiment of the present invention;

fig. 2 is a schematic diagram of another bridge displacement monitoring system based on visual perception provided by the embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures. Throughout this specification, the same or similar reference numbers refer to the same or similar structures, elements, or processes. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

Fig. 1 is the embodiment of the utility model provides a bridge displacement monitoring system's based on visual perception schematic diagram, as shown in fig. 1, bridge displacement monitoring system includes: a target 110, a vision sensor 120, and an image processing module 130.

Wherein the target 110 is disposed on the bridge; the vision sensor 120 includes a camera 121 and a lens 122 for acquiring a target image of the target; and the image processing module 130 is in communication connection with the vision sensor 120 and is used for processing the target image and calculating the bridge displacement.

Specifically, the target 110 is a target having a shape or pattern feature disposed on the bridge setting plane. The setting plane can be determined according to a specific monitored object, if the settlement of the bridge pier is mainly aimed at, a plane on the bridge pier, such as a plane at the center of the height of the bridge pier 1/3-2/3, is selected; if beam deflection is the primary concern, the target should be placed on the side of the beam of interest, on the same side as the vision sensor 120. The selected plane should be a flat, clean surface, and the set plane can be cleaned in advance if necessary.

Optionally, the target is a two-dimensional code target.

Specifically, the two-dimensional code target includes: the two-dimensional code bears carrier and two-dimensional code pattern. The two-dimension code pattern is arranged on the two-dimension code bearing carrier, the two-dimension code pattern is unique, and at least one rotating pattern of the current two-dimension code pattern rotating according to a set angle is not repeated with other two-dimension code patterns. The two-dimensional code pattern has uniqueness, and the two-dimensional code pattern of every two-dimensional code target that once bridge detection or monitoring related all is different promptly. Different bridges or different bridges are detected and monitored, and the two-dimensional code patterns of the related two-dimensional code targets can be the same. Uniqueness refers to relative uniqueness and not absolute uniqueness. Specifically, each two-dimensional code pattern may correspond to a unique identification information, such as a label or a coded information. The other two-dimension code patterns refer to two-dimension code patterns except the current two-dimension code pattern in the bridge detection or monitoring process, and are not repeated and are also relative to the current bridge detection or monitoring.

The set angle includes 90 °, 180 ° and 270 ° of counterclockwise rotation, and may further include 45 °, 135 ° and 225 °.

Optionally, the current two-dimensional code pattern is not repeated with other two-dimensional code patterns according to three rotation patterns rotated by 90 °, 180 ° and 270 ° counterclockwise and at least one of the current two-dimensional code pattern. Because the shape of two-dimensional code target generally is rectangle or square, when the installation, can have the condition of rotation unavoidably, the benefit that sets up like this lies in, no matter what the rotation angle of two-dimensional code target when the installation is, all can not influence the discernment to identity and the characteristic point of two-dimensional code target, has improved the suitability of two-dimensional code target for the installation of two-dimensional code target is more simple and easy.

Optionally, the two-dimensional code pattern is black and white in color. The two-dimensional code target has the advantages of being black and white, high in contrast and not prone to being interfered by environmental factors, and enabling the two-dimensional code target to have more obvious identification characteristics. And the less the kinds of colors, the better for the image processing. The two-dimensional code target with two colors is adopted, the size of the shot two-dimensional code target image is reduced, and the bridge detection efficiency is improved.

Specifically, the two-dimensional code pattern is located in the center of the two-dimensional code bearing carrier and occupies 10% -99% of the area of the two-dimensional code bearing carrier.

Optionally, the thickness of the two-dimensional code target is 0.05 mm-5 mm.

Optionally, the two-dimensional code pattern is an ArUco mark, an april tag mark, or a custom pattern. The ArUco marks are a lattice diagram of the Hamming code, a group of black frames are arranged on the periphery of each ArUco mark, and a two-dimensional matrix formed by black and white grids is arranged inside each ArUco mark. The black frame can accelerate the image processing speed, and the two-dimensional matrix is the identification information of the Aruco mark. The size of the Aruco label refers to the size of its internal two-dimensional matrix.

Optionally, the two-dimensional code bearing carrier is made of a diffuse reflection material. The diffuse reflection material can effectively avoid the unclear imaging. Specifically, a ceramic or glass flat plate can be used as the two-dimensional code bearing carrier. Optionally, the surface of the two-dimensional code bearing carrier is coated with aluminum oxide, so that the light-color consistency of the two-dimensional code bearing carrier is improved, and meanwhile, the high temperature resistance of the two-dimensional code target is improved. The thickness of the two-dimensional code target made of the ceramic or glass flat plate can be 2 mm-5 mm.

Optionally, a black frame is disposed at an edge of the two-dimensional code pattern, a white frame is disposed on the periphery of the black frame, and the width of the white frame is greater than or equal to the width of the black frame. The advantage of setting up like this lies in, can improve the contrast of the two-dimensional code pattern of two-dimensional code target for the discernment of the characteristic point of two-dimensional code pattern.

The edge can be any edge, two edges or three edges of the two-dimensional code pattern, or the periphery of the two-dimensional code pattern. The white frame may also be other bright or light-colored frames, such as yellow, blue, etc., and it is mainly necessary to form a clear contrast with the black frame to quickly identify the black frame.

Optionally, the two-dimensional code bearing carrier is a Polyvinyl chloride (PVC) sticker. Further, the two-dimensional code bearing carrier is special PVC outdoor paster. The two-dimensional code bearing carrier comprises a pasting layer, and the two-dimensional code target is fixed to a set plane through the pasting layer. The two-dimensional code target is fixed in a pasting mode, damage to the bridge body caused by the fact that nails, drills or other additional mechanical structures are adopted in the traditional method is avoided, and the pasting mode is easy to detach and low in cost.

Specifically, PVC adhesive sticker is used as a two-dimensional code bearing carrier, the thickness of the PVC adhesive sticker can be 0.05-0.5 mm, the cost is low, and the sticker has the advantages of being waterproof, not prone to fading, free of glue after being torn off and the like. The two-dimensional code target made of the PVC adhesive sticker material is light in weight, not easy to drop when being installed on a bridge, good in safety, free of actions of punching and the like to damage the bridge, and free of influence on service life and use of the bridge.

Optionally, the surface of the two-dimensional code bearing carrier is a surface subjected to matte treatment. The advantage that sets up like this lies in, has improved the optical property of two-dimensional code mark target, has formed dull and stereotyped surface like the dull polish through dumb membrane processing, is favorable to carrying out mark target formation of image.

Specifically, the two-dimensional code bearing carrier further comprises a waterproof film, an ink layer and a non-stick layer. Wherein, draw on the printing ink layer and have the two-dimensional code pattern, the water proof membrane is transparent, and the non-stick layer covers on pasting the layer, is the one deck of tearing easily.

Because the vision sensor 120 is used for acquiring the image of the target 110 on the bridge, the target needs to work for a certain time in an outdoor environment, which is often long-term monitoring, a metal shell needs to be arranged at the periphery of the vision sensor 120 to protect the vision sensor 120, such as water resistance, sun protection, theft prevention and the like, in order to ensure the normal work and the service life of the vision sensor 120 in the outdoor environment.

Optionally, an aluminum alloy shell is disposed at the periphery of the vision sensor 120, wherein the surface of the aluminum alloy shell is coated with an anti-corrosion protective paint.

The aluminum alloy shell has the characteristics of high mechanical strength, light weight, ultraviolet radiation resistance, moisture resistance, flame retardance and the like, and the surface of the aluminum alloy shell is coated with the anticorrosion protective paint, so that the outdoor working stability of the equipment is improved.

In addition, in order to prevent burglary, the visual sensor 120 can be placed in a place where people are not easy to contact, a small anti-theft concrete house can be poured, or a high vertical rod is erected to protect equipment.

Specifically, the working height of the tripod is 60 cm-170 cm, the tripod comprises a hydraulic damping tripod head, the pitching adjustment range of the tripod head is larger than +/-45 degrees, and the horizontal adjustment range is 360 degrees.

Optionally, the camera 121 is an industrial camera.

The model selection is carried out according to the detection distance and the precision, if long-distance (300 meters and above) and high-precision (millimeter level) bridge dynamic and static displacement measurement is selected, the camera 121 is an industrial camera with high resolution and small pixel size, such as the pixel size is lower than 3.45 mu m, the resolution is 4912 × 3684, and meanwhile, in order to monitor the change of bridge displacement in real time, the frame rate of the camera is not less than 5fps, namely at least 5 pictures per second can be shot.

Optionally, the camera 121 further includes a GigE interface or a USB3.0 interface, configured to transmit the target image to the image processing module. Wherein, the maximum transmission distance allowed by the GigE interface can reach 100 meters, and the transmission speed is also higher. The maximum transmission distance allowed by the USB3.0 interface is about 5 meters, the compatibility is good, the power consumption is low, and the transmission speed is very high.

The lens 122 is disposed on the camera 121, and specifically, the lens 122 and the camera 121 may be connected through a lens interface.

The lens 122 is a core element of the vision sensor 120, and the type of the lens is mainly determined by the observation distance. Optionally, the lens 122 includes a telephoto lens or a binocular lens. If the definition of imaging at an observation distance of more than 300 meters is met, a telephoto lens needs to be selected, and the focal length of the lens is more than 700 mm; if the observation distance is only a few meters, a binocular lens can be selected, the binocular lens can realize the measurement of three-dimensional deformation, but the requirement on the calibration of two lens parameters is very high, and the requirement is limited by installation conditions.

In addition, in order to facilitate the installation, integration and protection of the whole system equipment, the size of the lens is not suitable to be overlarge, the light weight is selected, the focal length range of the lens is 22.2 mm-755 mm, and the system can be applied to bridge displacement monitoring at various observation distances within the range of tens of meters to 500 meters.

Fig. 2 is a schematic view of another bridge displacement monitoring system based on visual perception provided by the embodiment of the present invention, referring to fig. 1 and 2. The bridge displacement monitoring system comprises a two-dimensional code target 210, a telephoto single-lens 220, an industrial camera 230, an inclinometer 240, an inclinometer flat plate 250 and an image processing module 260.

The inclinometer 240, the industrial camera 230 and the telephoto monocular head 220 are disposed on the inclinometer flat plate 250, and the inclinometer 240 and the camera 230 are located on the same horizontal plane.

Specifically, the inclinometer 240 is a biaxial inclinometer, which can ensure that the x-axis and the y-axis are measured simultaneously, the measurement precision should reach 0.01 °, and the effective range should be no less than ± 15 °. The angle information measured by the inclinometer 240 can be automatically called by the image processing module 160 for subsequent processing.

An inclinometer plate 250, comprising: dull and stereotyped main part, spout and inclinometer mounting hole. The sliding groove is arranged on the flat plate main body and used for mounting a camera and a lens so that the camera and the lens move along the sliding groove; the inclinometer mounting hole is formed in one side, far away from the sliding groove, of the flat plate main body and used for mounting the inclinometer. The flat main body is made of metal or alloy material with certain rigidity, and can not be obviously bent under the condition of loading of equipment such as a camera, a lens and the like. The inclinometer mounting holes 130 are at least 2 in number, and may be 3, 4, 6, or other number. The embodiment of the utility model provides a number, size and the shape of inclination appearance mounting hole all do not prescribe a limit to.

When the lens is installed, the gaps of the installation holes of different lenses are different, and the lens is installed in a sliding groove mode, so that the limitation of a punching mode is overcome, the lens is suitable for the lenses with various installation hole intervals, and the applicability of the inclinometer flat plate is improved.

Optionally, the material of the flat plate main body is an aircraft aluminum material, such as 7075 aluminum alloy. Other materials, such as metal materials of aluminum alloy, stainless steel, etc., may also be used.

Optionally, the thickness of the flat plate main body is 4-12 mm, and can be 6mm, 8mm or 10 mm. The thickness of the plate body may be determined according to the selected material and load bearing, the size of the mounting screws, or a combination thereof. When an aircraft aluminum material is used, the thickness of the plate body may be 8mm, taking into consideration both mechanical properties and cost. The flat main body is made of aviation aluminum with a certain thickness, so that the flat main body can be effectively prevented from being obviously bent under the action of loads of equipment such as a lens and the like, and the requirement on rigidity is met.

Optionally, the surface of the plate body is smoothed. The smoothness improves the flatness of the surface of the flat plate main body, is beneficial to subsequent displacement detection and improves the detection precision; meanwhile, the installation of the lens is facilitated, and the lens is prevented from being subjected to additional stress, so that the lens is prevented from being damaged.

Optionally, the movable distance of the chute is 5-20 cm. Optionally, the width of the sliding groove is 30-50 mm.

Optionally, the inclinometer mounting hole is fixed to the inclinometer through a hexagon socket head cap screw, so that stability of the inclinometer is guaranteed. Specifically, the hexagon socket head cap screw is made of stainless steel, and can be fixed by adopting a hexagon socket head cap screw of M5x 12.

Optionally, the flat plate main body comprises a rectangular main body and rectangular protrusions, the rectangular protrusions are located on one side of the rectangular main body, and the plate fixing holes are uniformly formed in the rectangular main body and used for fixing the inclinometer flat plate; the sliding chute is arranged in the rectangular main body; the inclinometer mounting hole is formed in the rectangular protrusion.

Optionally, the inclinometer flat plate further comprises an inclinometer shell, wherein the inclinometer shell is fixed on the inclinometer mounting hole and serves as the inclinometer shell. The shell is made of hard aluminum alloy, the protection grade is IP65, and the shell can adapt to the influence of various outdoor adverse environmental factors.

Specifically, the lighting device can also be placed at the periphery of the two-dimensional code bearing carrier, and an appropriate distance should be selected, so that the quality of the two-dimensional code pattern shooting is prevented from being influenced by halation of the L ED array while the two-dimensional code pattern is illuminated, and the distance between the L ED array and the two-dimensional code pattern can be determined according to the shooting distance and the property of light emitted by the L ED array, and can be 1-10 cm.

Illustratively, the two-dimensional code bearing carrier comprises a white frame, the two-dimensional code pattern is located in the white frame, and the L ED array can be uniformly placed at the white edge of the two-dimensional code bearing carrier and keeps a certain distance from the two-dimensional code pattern.

The lighting device is mainly applied to the condition that the ambient light brightness of the two-dimensional code target is weak, such as at night or in cloudy days. The night illumination is all to monitoring and detection very big usefulness, and the detection of traditional bridge is mostly gone on at night, needs to seal the bridge, and the measurement degree of difficulty is big night, and degree of automation is low. And the two-dimensional code target containing the lighting module is adopted, so that the bridge displacement monitoring or detection is automatically carried out at night or in other environments with weak illumination intensity, the cost is reduced, and the operation is simple and easy. The backlight mode is adopted for illumination, the defect that the requirement on the target is high due to the reflection or oblique incidence mode illumination is overcome, meanwhile, light pollution cannot be caused, the illumination effect is good, and the cost is low.

Optionally, the lighting device includes an array of light Emitting diodes (L light Emitting diodes, L ED) and a Flexible Printed Circuit (FPC).

Specifically, the light Emitting Diode (L light Emitting Diode, L ED) array and the Flexible Printed Circuit (FPC) adopt the existing commercial power on the bridge to supply power, such as the power supply of a bridge street lamp.

Specifically, the lighting equipment further comprises a cover plate, a light guide plate, a diffusion plate and the like, wherein the L ED array and the FPC flexible circuit are arranged in the cover plate, the two-dimensional code bearing carrier is pasted on the cover plate, the backlight type lighting mode is adopted for lighting, the lighting effect is good, the weight of the two-dimensional code target is reduced by adopting the FPC flexible circuit board, the installation is convenient, and safety accidents are avoided.

Specifically, the L ED array emits light of one color or a plurality of colors, the light can be one or a plurality of colors of red, white, yellow, green or blue, and the like, the number of the light can be 2, 4, 8 or more, the total optical power of the L ED array can be 15-30W, 18W, 25W and the like, so as to meet the illumination requirement and reduce the power consumption.

Optionally, in order to satisfy the long-term monitoring work, the system further includes: and the power supply module is electrically connected with the visual sensor and the image processing module and comprises a voltage conversion interface for supplying power to the visual sensor and the image processing module.

The power supply module is powered by mains supply, and the voltage conversion interface is a 12V/220V conversion interface.

Furthermore, the notebook also comprises an RJ45 crystal interface to transmit image data through a network cable, and in addition, in consideration of the need of data remote transmission, the notebook also needs to be ensured to have a sufficient USB interface, and the notebook also needs to have better cruising ability under long-term outdoor operation.

The data after image processing can be firstly stored in a local database, in addition, the notebook end is also provided with a special transfer program which can simultaneously support the server end and the client end and actively send the data to the platform database through a preset IP port. When the data is transmitted, the transfer program takes out the data in the local database and transmits the data to a remote system platform database through a wireless network, and the wireless transmission adopts a TCP/IP protocol. In addition, in order to ensure real-time transmission of data, wireless wifi and a telephone card are required to be equipped at the notebook terminal.

According to the technical scheme of the embodiment of the utility model, the two-dimensional code target containing the two-dimensional code pattern is used as the target for monitoring the displacement of the bridge, so that the target is not easily influenced by the environment, the stability is good, the installation is convenient, the limitation of the installation environment is avoided, the characteristic points of the two-dimensional code pattern are multidimensional, and the monitoring precision is high; the long-focus monocular head is used for collecting, so that long-distance and long-time bridge displacement monitoring is realized; measuring the included angle between the camera and the horizontal plane through an inclinometer; the inclinometer and the camera are fixed on the same horizontal plane through the inclinometer flat plate, so that the accuracy of the inclinometer for measuring the inclination angle of the camera is ensured, meanwhile, the chute is arranged, the position of the lens is conveniently adjusted, and the flexibility of the equipment is improved; an inclinometer mounting hole is further formed to fix the inclinometer and ensure the stability of the inclinometer; carry out near-end or distal end image processing in order to calculate the bridge displacement through image processing module, realized the automatic monitoring of bridge displacement, and system installation and operation are simple and easy, are difficult for receiving the restriction of environment, have still set up auxiliary assembly such as power module and lighting apparatus simultaneously, have guaranteed the normal operating of system, have improved the application scope of system simultaneously. The utility model provides a bridge displacement monitoring system, installation and operation are simple and easy, extensive applicability, stability are strong, the precision is high.

Claims

1. A bridge displacement monitoring system based on visual perception is characterized by comprising:

the target is arranged on the bridge;

2. The bridge displacement monitoring system of claim 1, wherein the target is a two-dimensional code target.

3. The bridge displacement monitoring system of claim 1, wherein an aluminum alloy shell is arranged on the periphery of the visual sensor, and a corrosion-proof protective paint is coated on the surface of the aluminum alloy shell.

4. The bridge displacement monitoring system of claim 1, wherein the lens comprises a tele-monocular or binocular lens.

5. The bridge displacement monitoring system of claim 1, wherein the lens comprises a tele monocular head, the system further comprising an inclinometer and an inclinometer plate, the inclinometer, the camera and the lens being disposed on the inclinometer plate, and the inclinometer and the camera being at a same horizontal plane.

6. The bridge displacement monitoring system of claim 5, further comprising: and the lighting device is a light emitting diode array and is arranged at the periphery or the back of the target, or the lighting device is an infrared light source and is arranged on the lens.

7. The bridge displacement monitoring system of claim 1, further comprising a tripod or a high upright, the visual sensor being located above the tripod or the high upright.

8. The bridge displacement monitoring system of claim 1, further comprising a power module electrically connected to the vision sensor and the image processing module, the power module including a voltage conversion interface for supplying power to the vision sensor and the image processing module.

9. The bridge displacement monitoring system of claim 1, wherein the image processing module is a laptop or a remote server.

10. The bridge displacement monitoring system of claim 1, wherein the camera further comprises a GigE interface or a USB3.0 interface for transmitting the target image to the image processing module.